Merge branch 'master' into branch-1.8

94 files changed, 2776 insertions, 1753 deletions

diff --git a/Releasing b/Releasing
index b8f8b75f..9a295f03 100644
--- a/Releasing
+++ b/Releasing
@@ -108,6 +108,7 @@ These are Bdale's notes on how to do a release.
 	   src/telegps-v2.0/{*.elf,*.ihx} \
 	   src/telemega-v1.0/{*.elf,*.ihx} \
 	   src/telemega-v2.0/{*.elf,*.ihx} \
+	   src/telemega-v3.0/{*.elf,*.ihx} \
 	   src/telemetrum-v2.0/{*.elf,*.ihx} \
 	   src/telemini-v3.0/{*.elf,*.ihx} \
 	   ~/altusmetrumllc/Binaries/
@@ -122,6 +123,7 @@ These are Bdale's notes on how to do a release.
 	   src/telegps-v2.0/flash-loader/*.elf \
 	   src/telemega-v1.0/flash-loader/*.elf \
 	   src/telemega-v2.0/flash-loader/*.elf \
+	   src/telemega-v3.0/flash-loader/*.elf \
 	   src/telemetrum-v2.0/flash-loader/*.elf \
 	   src/telemini-v3.0/flash-loader/{*.elf,*.bin} \
 	   ~/altusmetrumllc/Binaries/loaders/
diff --git a/ao-bringup/test-chaoskey b/ao-bringup/test-chaoskey
index f64b1f84..26684875 100755
--- a/ao-bringup/test-chaoskey
+++ b/ao-bringup/test-chaoskey
@@ -12,8 +12,8 @@ case "$#" in
 	serial="--serial $1"
 	;;
     0)
-	snum=`sudo dmesg | awk '/usb.*Product:/ { ck = index($0, "ChaosKey"); }
-		     /usb.*SerialNumber:/ { if (ck) print $5; }' | tail -1`
+	snum=`sudo dmesg -t | awk '/usb.*Product:/ { ck = index($0, "ChaosKey"); }
+		     /usb.*SerialNumber:/ { if (ck) print $4; }' | tail -1`
 
 	case "$snum" in
 	    "")
diff --git a/ao-bringup/turnon_easymini b/ao-bringup/turnon_easymini
index 9b66dc5e..7db72665 100755
--- a/ao-bringup/turnon_easymini
+++ b/ao-bringup/turnon_easymini
@@ -54,7 +54,7 @@ ALTOS_FILE=~/altusmetrumllc/Binaries/easymini-v2.0-*.elf
 
 echo $DFU_UTIL -a 0 -s 0x08000000:leave -D $FLASH_FILE
 
-#$DFU_UTIL -a 0 -s 0x08000000:leave -D $FLASH_FILE || exit 1
+$DFU_UTIL -a 0 -s 0x08000000:leave -D $FLASH_FILE || exit 1
 
 sleep 2
 
diff --git a/configure.ac b/configure.ac
index 02fca439..7f27dfad 100644
--- a/configure.ac
+++ b/configure.ac
@@ -18,13 +18,13 @@ dnl
 dnl Process this file with autoconf to create configure.
 
 AC_PREREQ(2.57)
-AC_INIT([altos], 1.8.3)
+AC_INIT([altos], 1.8.4)
 ANDROID_VERSION=16
 AC_CONFIG_SRCDIR([src/kernel/ao.h])
 AM_INIT_AUTOMAKE([foreign dist-bzip2])
 AM_MAINTAINER_MODE
 
-RELEASE_DATE=2017-12-11
+RELEASE_DATE=2017-12-21
 AC_SUBST(RELEASE_DATE)
 
 VERSION_DASH=`echo $VERSION | sed 's/\./-/g'`
diff --git a/doc/Makefile b/doc/Makefile
index feb1de8f..7d33149d 100644
--- a/doc/Makefile
+++ b/doc/Makefile
@@ -3,6 +3,7 @@
 #
 
 RELNOTES_INC=\
+	release-notes-1.8.4.inc \
 	release-notes-1.8.3.inc \
 	release-notes-1.8.2.inc \
 	release-notes-1.8.1.inc \
@@ -186,7 +187,6 @@ SVG=\
 	telemini-v3.svg \
 	easymega.svg
 
-RELNOTES_PDF=$(RELNOTES_INC:.inc=.pdf)
 RELNOTES_HTML=$(RELNOTES_INC:.inc=.html)
 
 ONEFILE_TXT_FILES=\
@@ -196,10 +196,13 @@ ONEFILE_TXT_FILES=\
 
 ONEFILE_RAW_FILES=$(ONEFILE_TXT_FILES:.txt=.raw)
 ONEFILE_PDF_FILES=$(ONEFILE_TXT_FILES:.txt=.pdf)
+ONEFILE_HTML_FILES=$(ONEFILE_TXT_FILES:.txt=.html)
 
 AM_HTML=am.html
 
-HTML=altusmetrum.html micropeak.html telegps.html easymini.html $(RELNOTES_HTML) $(ONEFILE_HTML_FILES)
+PUBLISH_HTML=altusmetrum.html micropeak.html telegps.html easymini.html $(ONEFILE_HTML_FILES)
+
+HTML=$(PUBLISH_HTML) $(RELNOTES_HTML)
 
 HTML_REVHISTORY=\
 	altusmetrum-revhistory.html \
@@ -207,7 +210,7 @@ HTML_REVHISTORY=\
 	telegps-revhistory.html \
 	easymini-revhistory.html
 
-PDF=altusmetrum.pdf micropeak.pdf telegps.pdf easymini.pdf $(RELNOTES_PDF) $(ONEFILE_PDF_FILES) \
+PDF=altusmetrum.pdf micropeak.pdf telegps.pdf easymini.pdf $(ONEFILE_PDF_FILES) \
 	$(OUTLINE_PDF_FILES)
 
 FOP_STYLE=am-fo.xsl
@@ -235,6 +238,8 @@ TEMPLATES_XSL=$(TEMPLATES_TMPL:.tmpl=.xsl)
 PDF_CONFIG_FILES=$(FOP_STYLE) $(COMMON_STYLE) $(FOP_XCONF) $(TEMPLATES_XSL)
 HTML_CONFIG_FILES=$(HTML_STYLE) $(COMMON_STYLE) $(TEMPLATES_XSL)
 
+PUBLISH_DOC=$(PUBLISH_HTML) $(HTML_REVHISTORY) $(PDF) $(IMAGES) $(STYLESHEET)
+
 DOC=$(HTML) $(HTML_REVHISTORY) $(PDF) $(IMAGES) $(STYLESHEET)
 
 .SUFFIXES: .tmpl .xsl .inc .txt .raw .pdf .html
@@ -245,12 +250,12 @@ DOC=$(HTML) $(HTML_REVHISTORY) $(PDF) $(IMAGES) $(STYLESHEET)
 .inc.raw:
 	sed -e 's/^[ 	]*//' -e 's/^\\//' $*.inc > $@
 
-.raw.pdf:
+.raw.html:
 	a2x --verbose -a docinfo -f pdf --xsltproc-opts "--stringparam toc.section.depth 2" --xsl-file $(FOP_STYLE) --fop --fop-opts="-c $(FOP_XCONF)" $*.raw
 	a2x --verbose -a docinfo -f xhtml --xsltproc-opts "--stringparam toc.section.depth 2" --xsl-file $(HTML_STYLE) --stylesheet=$(STYLESHEET) $*.raw
 	case $* in release-notes*) ./fix-html $*.html ;; esac
 
-.pdf.html:
+.html.pdf:
 	@touch $@
 
 .tmpl.xsl:
@@ -278,19 +283,21 @@ telemini-v3-outline.pdf: telemini-v3-outline.txt telemini-v3.svg
 
 install:	all
 
-publish:	$(DOC) $(FONTS)
-	cp $(DOC) /home/bdale/web/altusmetrum/AltOS/doc/
-	mkdir -p /home/bdale/web/altusmetrum/AltOS/doc/fonts/
-	cp $(FONTS) /home/bdale/web/altusmetrum/AltOS/doc/fonts/
-	(cd /home/bdale/web/altusmetrum ; \
-	 git add /home/bdale/web/altusmetrum/AltOS/doc/* ; \
-	 git add /home/bdale/web/altusmetrum/AltOS/doc/fonts/* ; \
+WEB_ROOT=/home/bdale/web/
+
+publish:	$(PUBLISH_DOC) $(FONTS)
+	cp $(PUBLISH_DOC) $(WEB_ROOT)/altusmetrum/AltOS/doc/
+	mkdir -p $(WEB_ROOT)/altusmetrum/AltOS/doc/fonts/
+	cp $(FONTS) $(WEB_ROOT)/altusmetrum/AltOS/doc/fonts/
+	(cd $(WEB_ROOT)/altusmetrum ; \
+	 git add $(WEB_ROOT)/altusmetrum/AltOS/doc/* ; \
+	 git add $(WEB_ROOT)/altusmetrum/AltOS/doc/fonts/* ; \
 	 echo "update docs" | \
-	 git commit -F - /home/bdale/web/altusmetrum/AltOS/doc/* /home/bdale/web/altusmetrum/AltOS/doc/fonts/* ; \
+	 git commit -F - $(WEB_ROOT)/altusmetrum/AltOS/doc/* $(WEB_ROOT)/altusmetrum/AltOS/doc/fonts/* ; \
 	 git push)
 
-publish-keithp:	am.html $(DOC) $(FONTS)
-	scp -p am.html $(DOC) keithp.com:~keithp/public_html/altos
+publish-keithp:	am.html $(PUBLISH_DOC) $(FONTS)
+	scp -p am.html $(PUBLISH_DOC) keithp.com:~keithp/public_html/altos
 	scp -p $(FONTS) keithp.com:~keithp/public_html/altos/fonts
 
 clean:
diff --git a/doc/RELNOTES b/doc/RELNOTES
index 8f7d2540..c3980882 100644
--- a/doc/RELNOTES
+++ b/doc/RELNOTES
@@ -1,7 +1,6 @@
 Creating documentation for a new release of AltOS
 
-* Write release notes in release-notes-${version}.inc. Write docinfo
-  for release notes in release-notes-${version}-docinfo.xml. Add to
+* Write release notes in release-notes-${version}.inc. Add to
   Makefile
 
 * Add references to that as appropriate from each of the
@@ -30,5 +29,4 @@ Creating documentation for a new release of AltOS
 	telegps-docinfo.xml
 	telemetry-docinfo.xml
 
-* Add release-notes-${version}.inc and
-  release-notes-${version}-docinfo.xml to git
+* Add release-notes-${version}.inc to git
diff --git a/doc/altusmetrum-docinfo.xml b/doc/altusmetrum-docinfo.xml
index 3b0793b8..235111fc 100644
--- a/doc/altusmetrum-docinfo.xml
+++ b/doc/altusmetrum-docinfo.xml
@@ -47,6 +47,13 @@
 <revhistory>
   <?dbhtml filename="altusmetrum-revhistory.html"?>
   <revision>
+    <revnumber>1.8.4</revnumber>
+    <date>20 Dec 2017</date>
+    <revremark>
+      Support EasyMini v2.0 hardware.
+    </revremark>
+  </revision>
+  <revision>
     <revnumber>1.8.3</revnumber>
     <date>11 Dec 2017</date>
     <revremark>
diff --git a/doc/easymini-docinfo.xml b/doc/easymini-docinfo.xml
index cf3f27d2..85baba1e 100644
--- a/doc/easymini-docinfo.xml
+++ b/doc/easymini-docinfo.xml
@@ -39,6 +39,13 @@
 <revhistory>
   <?dbhtml filename="easymini-revhistory.html"?>
   <revision>
+    <revnumber>1.8.4</revnumber>
+    <date>20 Dec 2017</date>
+    <revremark>
+      Support EasyMini v2.0 hardware.
+    </revremark>
+  </revision>
+  <revision>
     <revnumber>1.6.3</revnumber>
     <date>21 April 2016</date>
     <revremark>
diff --git a/doc/easymini-release-notes.inc b/doc/easymini-release-notes.inc
index f4f45fd7..dae928a6 100644
--- a/doc/easymini-release-notes.inc
+++ b/doc/easymini-release-notes.inc
@@ -1,6 +1,10 @@
 [appendix]
 == Release Notes
 	:leveloffset: 2
+	include::release-notes-1.8.4.raw[]
+
+	<<<<
+	:leveloffset: 2
 	include::release-notes-1.8.3.raw[]
 
 	<<<<
diff --git a/doc/release-notes-0.7.1-docinfo.xml b/doc/release-notes-0.7.1-docinfo.xml
deleted file mode 100644
index 9657f2a6..00000000
--- a/doc/release-notes-0.7.1-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>29 September 2010</date>
-<copyright>
-  <year>2010</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-0.8-docinfo.xml b/doc/release-notes-0.8-docinfo.xml
deleted file mode 100644
index d593da31..00000000
--- a/doc/release-notes-0.8-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>24 November 2010</date>
-<copyright>
-  <year>2010</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-0.9-docinfo.xml b/doc/release-notes-0.9-docinfo.xml
deleted file mode 100644
index 605472f2..00000000
--- a/doc/release-notes-0.9-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>18 January 2011</date>
-<copyright>
-  <year>2011</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-0.9.2-docinfo.xml b/doc/release-notes-0.9.2-docinfo.xml
deleted file mode 100644
index 40e53634..00000000
--- a/doc/release-notes-0.9.2-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>19 March 2011</date>
-<copyright>
-  <year>2011</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.0.1-docinfo.xml b/doc/release-notes-1.0.1-docinfo.xml
deleted file mode 100644
index 23972104..00000000
--- a/doc/release-notes-1.0.1-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>24 August 2011</date>
-<copyright>
-  <year>2011</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.1-docinfo.xml b/doc/release-notes-1.1-docinfo.xml
deleted file mode 100644
index 93273918..00000000
--- a/doc/release-notes-1.1-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>13 September 2012</date>
-<copyright>
-  <year>2013</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.1.1-docinfo.xml b/doc/release-notes-1.1.1-docinfo.xml
deleted file mode 100644
index 41ea12da..00000000
--- a/doc/release-notes-1.1.1-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>16 September 2012</date>
-<copyright>
-  <year>2012</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.2-docinfo.xml b/doc/release-notes-1.2-docinfo.xml
deleted file mode 100644
index ba2c9d56..00000000
--- a/doc/release-notes-1.2-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>18 April 2013</date>
-<copyright>
-  <year>2013</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.2.1-docinfo.xml b/doc/release-notes-1.2.1-docinfo.xml
deleted file mode 100644
index d0f08b9c..00000000
--- a/doc/release-notes-1.2.1-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>21 May 2013</date>
-<copyright>
-  <year>2013</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.3-docinfo.xml b/doc/release-notes-1.3-docinfo.xml
deleted file mode 100644
index aa569df4..00000000
--- a/doc/release-notes-1.3-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>12 November 2013</date>
-<copyright>
-  <year>2013</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.3.1-docinfo.xml b/doc/release-notes-1.3.1-docinfo.xml
deleted file mode 100644
index f67cf3b8..00000000
--- a/doc/release-notes-1.3.1-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>21 January 2014</date>
-<copyright>
-  <year>2014</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.3.2-docinfo.xml b/doc/release-notes-1.3.2-docinfo.xml
deleted file mode 100644
index 82b7677e..00000000
--- a/doc/release-notes-1.3.2-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>24 January 2014</date>
-<copyright>
-  <year>2014</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.4-docinfo.xml b/doc/release-notes-1.4-docinfo.xml
deleted file mode 100644
index 12a38ce5..00000000
--- a/doc/release-notes-1.4-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>15 June 2014</date>
-<copyright>
-  <year>2014</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.4.1-docinfo.xml b/doc/release-notes-1.4.1-docinfo.xml
deleted file mode 100644
index 6224b16e..00000000
--- a/doc/release-notes-1.4.1-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>20 June 2014</date>
-<copyright>
-  <year>2014</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.4.2-docinfo.xml b/doc/release-notes-1.4.2-docinfo.xml
deleted file mode 100644
index 8fd94324..00000000
--- a/doc/release-notes-1.4.2-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>17 August 2014</date>
-<copyright>
-  <year>2014</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.5-docinfo.xml b/doc/release-notes-1.5-docinfo.xml
deleted file mode 100644
index 0c0cace7..00000000
--- a/doc/release-notes-1.5-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>6 September 2014</date>
-<copyright>
-  <year>2014</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.6-docinfo.xml b/doc/release-notes-1.6-docinfo.xml
deleted file mode 100644
index 5ae58bb5..00000000
--- a/doc/release-notes-1.6-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>8 January 2015</date>
-<copyright>
-  <year>2015</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.6.1-docinfo.xml b/doc/release-notes-1.6.1-docinfo.xml
deleted file mode 100644
index dc0a2d67..00000000
--- a/doc/release-notes-1.6.1-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>15 July 2015</date>
-<copyright>
-  <year>2015</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.6.2-docinfo.xml b/doc/release-notes-1.6.2-docinfo.xml
deleted file mode 100644
index 78206e2a..00000000
--- a/doc/release-notes-1.6.2-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>10 January 2016</date>
-<copyright>
-  <year>2016</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.6.3-docinfo.xml b/doc/release-notes-1.6.3-docinfo.xml
deleted file mode 100644
index ce22ebcb..00000000
--- a/doc/release-notes-1.6.3-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>6 May 2016</date>
-<copyright>
-  <year>2016</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.6.4-docinfo.xml b/doc/release-notes-1.6.4-docinfo.xml
deleted file mode 100644
index 76af3557..00000000
--- a/doc/release-notes-1.6.4-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>17 June 2016</date>
-<copyright>
-  <year>2016</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.6.5-docinfo.xml b/doc/release-notes-1.6.5-docinfo.xml
deleted file mode 100644
index a07d6f0f..00000000
--- a/doc/release-notes-1.6.5-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>4 July 2016</date>
-<copyright>
-  <year>2016</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.6.8-docinfo.xml b/doc/release-notes-1.6.8-docinfo.xml
deleted file mode 100644
index 776c244c..00000000
--- a/doc/release-notes-1.6.8-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>5 September 2016</date>
-<copyright>
-  <year>2016</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.7-docinfo.xml b/doc/release-notes-1.7-docinfo.xml
deleted file mode 100644
index 61d77d92..00000000
--- a/doc/release-notes-1.7-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>24 April 2017</date>
-<copyright>
-  <year>2017</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.8-docinfo.xml b/doc/release-notes-1.8-docinfo.xml
deleted file mode 100644
index 3b40421a..00000000
--- a/doc/release-notes-1.8-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>12 August 2017</date>
-<copyright>
-  <year>2017</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.8.1-docinfo.xml b/doc/release-notes-1.8.1-docinfo.xml
deleted file mode 100644
index 29a4fe7a..00000000
--- a/doc/release-notes-1.8.1-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>28 August 2017</date>
-<copyright>
-  <year>2017</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.8.2-docinfo.xml b/doc/release-notes-1.8.2-docinfo.xml
deleted file mode 100644
index a5fbc6e2..00000000
--- a/doc/release-notes-1.8.2-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>18 September 2017</date>
-<copyright>
-  <year>2017</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.8.3-docinfo.xml b/doc/release-notes-1.8.3-docinfo.xml
deleted file mode 100644
index e0366586..00000000
--- a/doc/release-notes-1.8.3-docinfo.xml
+++ /dev/null
@@ -1,29 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<date>11 December 2017</date>
-<copyright>
-  <year>2017</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="altusmetrum-oneline.svg" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes-1.8.4.inc b/doc/release-notes-1.8.4.inc
new file mode 100644
index 00000000..f8cb4f11
--- /dev/null
+++ b/doc/release-notes-1.8.4.inc
@@ -0,0 +1,9 @@
+= Release Notes for Version 1.8.4
+:toc!:
+:doctype: article
+
+	Version 1.8.4 includes support for EasyMini version 2.0
+
+	== AltOS
+
+	* Support for EasyMini version 2.0 hardware.
diff --git a/doc/release-notes-docinfo.xml b/doc/release-notes-docinfo.xml
deleted file mode 100644
index 4f842cde..00000000
--- a/doc/release-notes-docinfo.xml
+++ /dev/null
@@ -1,28 +0,0 @@
-<author>
-  <firstname>Bdale</firstname>
-  <surname>Garbee</surname>
-  <email>bdale@gag.com</email>
-</author>
-<author>
-  <firstname>Keith</firstname>
-  <surname>Packard</surname>
-  <email>keithp@keithp.com</email>
-</author>
-<copyright>
-  <year>2015</year>
-  <holder>Bdale Garbee and Keith Packard</holder>
-</copyright>
-<mediaobject>
-  <imageobject>
-    <imagedata fileref="../themes/background.png" width="6.0in"/>
-  </imageobject>
-</mediaobject>
-<legalnotice>
-  <para>
-    This document is released under the terms of the
-    <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
-      Creative Commons ShareAlike 3.0
-    </ulink>
-    license.
-  </para>
-</legalnotice>
diff --git a/doc/release-notes.inc b/doc/release-notes.inc
index 1c177afa..50b27ab5 100644
--- a/doc/release-notes.inc
+++ b/doc/release-notes.inc
@@ -2,6 +2,11 @@
 == Release Notes
 
 	:leveloffset: 2
+	include::release-notes-1.8.4.raw[]
+
+	<<<<
+
+	:leveloffset: 2
 	include::release-notes-1.8.3.raw[]
 
 	<<<<
diff --git a/doc/telegps-release-notes.inc b/doc/telegps-release-notes.inc
index 0c506c28..5c5da8f6 100644
--- a/doc/telegps-release-notes.inc
+++ b/doc/telegps-release-notes.inc
@@ -2,6 +2,11 @@
 == Release Notes
 
 	:leveloffset: 2
+	include::release-notes-1.8.4.raw[]
+
+	<<<<
+
+	:leveloffset: 2
 	include::release-notes-1.8.3.raw[]
 
 	<<<<
diff --git a/src/attiny/ao_adc_attiny.c b/src/attiny/ao_adc_attiny.c
new file mode 100644
index 00000000..3a835d13
--- /dev/null
+++ b/src/attiny/ao_adc_attiny.c
@@ -0,0 +1,48 @@
+/*
+ * Copyright © 2017 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#include <ao.h>
+
+/*
+ * ATtiny ADC interface
+ */
+
+uint16_t
+ao_adc_read(uint8_t mux)
+{
+	uint8_t	low, high;
+
+	/* Set the mux */
+	ADMUX = mux;
+
+	/* Start conversion */
+	ADCSRA = ((1 << ADEN) |
+		  (1 << ADSC) |
+		  (0 << ADATE) |
+		  (0 << ADIF) |
+		  (0 << ADIE) |
+		  (0 << ADPS2) |
+		  (0 << ADPS1) |
+		  (0 << ADPS0));
+
+	/* Await conversion complete */
+	while ((ADCSRA & (1 << ADSC)) != 0)
+		;
+
+	/* Read low first */
+	low = ADCL;
+	high = ADCH;
+
+	return (((uint16_t) high) << 8) | low;
+}
diff --git a/src/attiny/ao_arch.h b/src/attiny/ao_arch.h
index 3a34f417..68f5702d 100644
--- a/src/attiny/ao_arch.h
+++ b/src/attiny/ao_arch.h
@@ -85,4 +85,7 @@ ao_eeprom_read(uint16_t addr, void *buf, uint16_t len);
 void
 ao_eeprom_write(uint16_t addr, void *buf, uint16_t len);
 
+uint16_t
+ao_adc_read(uint8_t mux);
+
 #endif /* _AO_ARCH_H_ */
diff --git a/src/easymini-v2.0/ao_pins.h b/src/easymini-v2.0/ao_pins.h
index 2ec0e90b..47eb577e 100644
--- a/src/easymini-v2.0/ao_pins.h
+++ b/src/easymini-v2.0/ao_pins.h
@@ -60,11 +60,11 @@
 #define HAS_IGNITE		1
 #define HAS_IGNITE_REPORT	1
 
-/* Beeper is on Tim3 CH3 */
+/* Beeper is on Tim3 CH4 */
 #define BEEPER_TIMER		3
-#define BEEPER_CHANNEL		3
+#define BEEPER_CHANNEL		4
 #define BEEPER_PORT		(&stm_gpiob)
-#define BEEPER_PIN		0
+#define BEEPER_PIN		1
 #define BEEPER_AFR		STM_AFR_AF1
 
 /* SPI */
@@ -130,8 +130,8 @@ struct ao_adc {
 #define AO_IGNITER_CLOSED	400
 #define AO_IGNITER_OPEN		60
 
-#define AO_IGNITER_DROGUE_PORT	(&stm_gpiob)
-#define AO_IGNITER_DROGUE_PIN	6
+#define AO_IGNITER_DROGUE_PORT	(&stm_gpioa)
+#define AO_IGNITER_DROGUE_PIN	3
 #define AO_IGNITER_SET_DROGUE(v)	ao_gpio_set(AO_IGNITER_DROGUE_PORT, AO_IGNITER_DROGUE_PIN, AO_IGNITER_DROGUE, v)
 
 #define AO_IGNITER_MAIN_PORT	(&stm_gpiob)
diff --git a/src/easymini-v2.0/flash-loader/ao_pins.h b/src/easymini-v2.0/flash-loader/ao_pins.h
index 3098fc22..9cba43e5 100644
--- a/src/easymini-v2.0/flash-loader/ao_pins.h
+++ b/src/easymini-v2.0/flash-loader/ao_pins.h
@@ -21,11 +21,11 @@
 
 #include <ao_flash_stm_pins.h>
 
-/* pin 5 (PB1) on debug header to gnd for boot mode */
+/* pin 27 (PB6) on debug header to gnd for boot mode */
 
 #define AO_BOOT_PIN			1
 #define AO_BOOT_APPLICATION_GPIO	stm_gpiob
-#define AO_BOOT_APPLICATION_PIN		1
+#define AO_BOOT_APPLICATION_PIN		6
 #define AO_BOOT_APPLICATION_VALUE	1
 #define AO_BOOT_APPLICATION_MODE	AO_EXTI_MODE_PULL_UP
 
diff --git a/src/kernel/ao.h b/src/kernel/ao.h
index 139050cf..2bd0e367 100644
--- a/src/kernel/ao.h
+++ b/src/kernel/ao.h
@@ -218,6 +218,9 @@ ao_cmd_register(const __code struct ao_cmds *cmds);
 void
 ao_cmd_init(void);
 
+void
+ao_cmd(void);
+
 #if HAS_CMD_FILTER
 /*
  * Provided by an external module to filter raw command lines
diff --git a/src/kernel/ao_cmd.c b/src/kernel/ao_cmd.c
index c1e9cef2..405fd126 100644
--- a/src/kernel/ao_cmd.c
+++ b/src/kernel/ao_cmd.c
@@ -423,11 +423,13 @@ ao_loader(void)
 }
 #endif
 
+#if HAS_TASK
 __xdata struct ao_task ao_cmd_task;
+#endif
 
 __code struct ao_cmds	ao_base_cmds[] = {
 	{ help,		"?\0Help" },
-#if HAS_TASK_INFO
+#if HAS_TASK_INFO && HAS_TASK
 	{ ao_task_info,	"T\0Tasks" },
 #endif
 	{ echo,		"E <0 off, 1 on>\0Echo" },
@@ -445,5 +447,7 @@ void
 ao_cmd_init(void)
 {
 	ao_cmd_register(&ao_base_cmds[0]);
+#if HAS_TASK
 	ao_add_task(&ao_cmd_task, ao_cmd, "cmd");
+#endif
 }
diff --git a/src/kernel/ao_notask.c b/src/kernel/ao_notask.c
index 00fe1ed6..7207353a 100644
--- a/src/kernel/ao_notask.c
+++ b/src/kernel/ao_notask.c
@@ -39,6 +39,21 @@ ao_sleep(__xdata void *wchan)
 	return 0;
 }
 
+#if HAS_AO_DELAY
+void
+ao_delay(uint16_t ticks)
+{
+	AO_TICK_TYPE	target;
+
+	if (!ticks)
+		ticks = 1;
+	target = ao_tick_count + ticks;
+	do {
+		ao_sleep(&ao_time);
+	} while ((int16_t) (target - ao_tick_count) > 0);
+}
+#endif
+
 void
 ao_wakeup(__xdata void *wchan)
 {
diff --git a/src/lambdakey-v1.0/.gitignore b/src/lambdakey-v1.0/.gitignore
index 6462d930..a57994e8 100644
--- a/src/lambdakey-v1.0/.gitignore
+++ b/src/lambdakey-v1.0/.gitignore
@@ -1,2 +1,3 @@
 lambdakey-*
 ao_product.h
+ao_scheme_const.h
diff --git a/src/lambdakey-v1.0/Makefile b/src/lambdakey-v1.0/Makefile
index 4eb045b6..bffe7d4f 100644
--- a/src/lambdakey-v1.0/Makefile
+++ b/src/lambdakey-v1.0/Makefile
@@ -20,6 +20,7 @@ INC = \
 	ao_product.h \
 	ao_task.h \
 	$(SCHEME_HDRS) \
+	ao_scheme_const.h \
 	stm32f0.h \
 	Makefile
 
@@ -27,20 +28,16 @@ ALTOS_SRC = \
 	ao_boot_chain.c \
 	ao_interrupt.c \
 	ao_product.c \
-	ao_romconfig.c \
 	ao_cmd.c \
-	ao_config.c \
-	ao_task.c \
+	ao_notask.c \
 	ao_led.c \
-	ao_dma_stm.c \
 	ao_stdio.c \
-	ao_mutex.c \
+	ao_stdio_newlib.c \
 	ao_panic.c \
 	ao_timer.c \
 	ao_usb_stm.c \
-	ao_flash_stm.c \
-	$(SCHEME_SRCS) \
-	ao_scheme_os_save.c
+	ao_romconfig.c \
+	$(SCHEME_SRCS)
 
 PRODUCT=LambdaKey-v1.0
 PRODUCT_DEF=-DLAMBDAKEY
@@ -65,7 +62,7 @@ OBJ=$(SRC:.c=.o)
 
 all: $(PROG) $(HEX)
 
-$(PROG): Makefile $(OBJ) lambda.ld altos.ld
+$(PROG): Makefile $(OBJ) lambda.ld
 	$(call quiet,CC) $(LDFLAGS) $(CFLAGS) -o $(PROG) $(OBJ) $(LIBS)
 
 $(OBJ): $(INC)
@@ -73,13 +70,16 @@ $(OBJ): $(INC)
 ao_product.h: ao-make-product.5c ../Version
 	$(call quiet,NICKLE,$<) $< -m altusmetrum.org -i $(IDPRODUCT) -p $(PRODUCT) -v $(VERSION) > $@
 
+ao_scheme_const.h: ../scheme/make-const/ao_scheme_make_const ao_lambdakey_const.scheme
+	../scheme/make-const/ao_scheme_make_const -d FLOAT,VECTOR,QUASI,BIGINT -o $@ ao_lambdakey_const.scheme
+
 load: $(PROG)
 	stm-load $(PROG)
 
 distclean:	clean
 
 clean:
-	rm -f *.o $(PROGNAME)-*.elf $(PROGNAME)-*.ihx
+	rm -f *.o $(PROGNAME)-*.elf $(PROGNAME)-*.ihx ao_scheme_const.h
 	rm -f ao_product.h
 
 install:
diff --git a/src/lambdakey-v1.0/ao_lambdakey.c b/src/lambdakey-v1.0/ao_lambdakey.c
index d0996eb4..73962e29 100644
--- a/src/lambdakey-v1.0/ao_lambdakey.c
+++ b/src/lambdakey-v1.0/ao_lambdakey.c
@@ -29,13 +29,11 @@ void main(void)
 {
 	ao_led_init(LEDS_AVAILABLE);
 	ao_clock_init();
-	ao_task_init();
 	ao_timer_init();
-	ao_dma_init();
 	ao_usb_init();
 	ao_cmd_init();
 	ao_cmd_register(blink_cmds);
-	ao_start_scheduler();
+	ao_cmd();
 }
 
 
diff --git a/src/lambdakey-v1.0/ao_lambdakey_const.scheme b/src/lambdakey-v1.0/ao_lambdakey_const.scheme
new file mode 100644
index 00000000..a912b8ae
--- /dev/null
+++ b/src/lambdakey-v1.0/ao_lambdakey_const.scheme
@@ -0,0 +1,428 @@
+;
+; Copyright © 2016 Keith Packard <keithp@keithp.com>
+;
+; This program is free software; you can redistribute it and/or modify
+; it under the terms of the GNU General Public License as published by
+; the Free Software Foundation, either version 2 of the License, or
+; (at your option) any later version.
+;
+; This program is distributed in the hope that it will be useful, but
+; WITHOUT ANY WARRANTY; without even the implied warranty of
+; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+; General Public License for more details.
+;
+; Lisp code placed in ROM
+
+					; return a list containing all of the arguments
+(def (quote list) (lambda l l))
+
+(def (quote def!)
+     (macro (a b)
+	    (list
+	     def
+	     (list quote a)
+	     b)
+	    )
+     )
+
+(begin
+ (def! append
+   (lambda args
+	  (def! a-l
+	    (lambda (a b)
+	      (cond ((null? a) b)
+		    (else (cons (car a) (a-l (cdr a) b)))
+		    )
+	      )
+	    )
+	    
+	  (def! a-ls
+	    (lambda (l)
+	      (cond ((null? l) l)
+		    ((null? (cdr l)) (car l))
+		    (else (a-l (car l) (a-ls (cdr l))))
+		    )
+	      )
+	    )
+	  (a-ls args)
+	  )
+   )
+ 'append)
+
+(append '(a) '(b))
+
+					;
+					; Define a variable without returning the value
+					; Useful when defining functions to avoid
+					; having lots of output generated.
+					;
+					; Also accepts the alternate
+					; form for defining lambdas of
+					; (define (name a y z) sexprs ...) 
+					;
+
+(begin
+ (def (quote define)
+   (macro (a . b)
+					; check for alternate lambda definition form
+
+	  (cond ((pair? a)
+		 (set! b
+		       (cons lambda (cons (cdr a) b)))
+		 (set! a (car a))
+		 )
+		(else
+		 (set! b (car b))
+		 )
+		)
+	  (cons begin
+		(cons
+		 (cons def
+		       (cons (cons quote (cons a '()))
+			     (cons b '())
+			     )
+		       )
+		 (cons
+		  (cons quote (cons a '()))
+		  '())
+		 )
+		)
+	  )
+   )
+ 'define
+ )
+
+					; boolean operators
+
+(begin
+ (def! or
+   (macro a
+	  (def! _or
+	    (lambda (a)
+	      (cond ((null? a) #f)
+		    ((null? (cdr a))
+		     (car a))
+		    (else
+		     (list
+		      cond
+		      (list
+		       (car a))
+		      (list
+		       'else
+		       (_or (cdr a))
+		       )
+		      )
+		     )
+		    )
+	      )
+	    )
+	  (_or a)))
+ 'or)
+
+					; execute to resolve macros
+
+(or #f #t)
+
+(begin
+ (def! and
+   (macro a
+	  (def! _and
+	    (lambda (a)
+	      (cond ((null? a) #t)
+		    ((null? (cdr a))
+		     (car a))
+		    (else
+		     (list
+		      cond
+		      (list
+		       (car a)
+		       (_and (cdr a))
+		       )
+		      )
+		     )
+		    )
+	      )
+	    )
+	  (_and a)
+	  )
+   )
+ 'and)
+
+					; execute to resolve macros
+
+(and #t #f)
+
+					; basic list accessors
+
+(define (caar a) (car (car a)))
+
+(define (cadr a) (car (cdr a)))
+
+; (define (cdar a) (cdr (car a)))
+
+					; (if <condition> <if-true>)
+					; (if <condition> <if-true> <if-false)
+
+(define if
+  (macro (test . b)
+    (cond ((null? (cdr b))
+	   (list cond (list test (car b)))
+		)
+	  (else
+	   (list cond
+		 (list test (car b))
+		 (list 'else (cadr b))
+		 )
+	   )
+	  )
+    )
+  )
+
+(if (> 3 2) 'yes)
+(if (> 3 2) 'yes 'no)
+(if (> 2 3) 'no 'yes)
+(if (> 2 3) 'no)
+
+					; simple math operators
+
+(define zero? (macro (value) (list eqv? value 0)))
+
+(zero? 1)
+(zero? 0)
+(zero? "hello")
+
+(define positive? (macro (value) (list > value 0)))
+
+(positive? 12)
+(positive? -12)
+
+(define negative? (macro (value) (list < value 0)))
+
+(negative? 12)
+(negative? -12)
+
+(define (abs a) (if (>= a 0) a (- a)))
+
+(abs 12)
+(abs -12)
+
+(define max (lambda (a . b)
+		   (while (not (null? b))
+		     (cond ((< a (car b))
+			    (set! a (car b)))
+			   )
+		     (set! b (cdr b))
+		     )
+		   a)
+  )
+
+(max 1 2 3)
+(max 3 2 1)
+
+(define min (lambda (a . b)
+		   (while (not (null? b))
+		     (cond ((> a (car b))
+			    (set! a (car b)))
+			   )
+		     (set! b (cdr b))
+		     )
+		   a)
+  )
+
+(min 1 2 3)
+(min 3 2 1)
+
+(define (even? a) (zero? (% a 2)))
+
+(even? 2)
+(even? -2)
+(even? 3)
+(even? -1)
+
+(define (odd? a) (not (even? a)))
+
+(odd? 2)
+(odd? -2)
+(odd? 3)
+(odd? -1)
+
+
+(define (list-tail a b)
+  (if (zero? b)
+      a
+      (list-tail (cdr a) (- b 1))
+      )
+  )
+
+(define (list-ref a b)
+  (car (list-tail a b))
+  )
+
+(list-ref '(1 2 3) 2)
+    
+
+					; define a set of local
+					; variables one at a time and
+					; then evaluate a list of
+					; sexprs
+					;
+					; (let* (var-defines) sexprs)
+					;
+					; where var-defines are either
+					;
+					; (name value)
+					;
+					; or
+					;
+					; (name)
+					;
+					; e.g.
+					;
+					; (let* ((x 1) (y)) (set! y (+ x 1)) y)
+
+(define let*
+  (macro (a . b)
+
+					;
+					; make the list of names in the let
+					;
+
+	 (define (_n a)
+	   (cond ((not (null? a))
+		  (cons (car (car a))
+			(_n (cdr a))))
+		 (else ())
+		 )
+	   )
+
+					; the set of expressions is
+					; the list of set expressions
+					; pre-pended to the
+					; expressions to evaluate
+
+	 (define (_v a b)
+	   (cond ((null? a) b)		 (else
+		  (cons
+		   (list set
+			 (list quote
+			       (car (car a))
+			       )
+			 (cond ((null? (cdr (car a))) ())
+			       (else (cadr (car a))))
+			 )
+		   (_v (cdr a) b)
+		   )
+		  )
+		 )
+	   )
+
+					; the parameters to the lambda is a list
+					; of nils of the right length
+
+	 (define (_z a)
+	   (cond ((null? a) ())
+		 (else (cons () (_z (cdr a))))
+		 )
+	   )
+					; build the lambda.
+
+	 (cons (cons lambda (cons (_n a) (_v a b))) (_z a))
+	 )
+     )
+
+(let* ((a 1) (y a)) (+ a y))
+
+(define let let*)
+					; recursive equality
+
+(define (equal? a b)
+  (cond ((eq? a b) #t)
+	((pair? a)
+	 (cond ((pair? b)
+		(cond ((equal? (car a) (car b))
+		       (equal? (cdr a) (cdr b)))
+		      )
+		)
+	       )
+	 )
+	)
+  )
+
+(equal? '(a b c) '(a b c))
+(equal? '(a b c) '(a b b))
+
+(define (member a b . t?)
+  (cond ((null? b)
+	 #f
+	 )
+	(else
+	 (if (null? t?) (set! t? equal?) (set! t? (car t?)))
+	 (if (t? a (car b))
+	     b
+	     (member a (cdr b) t?))
+	 )
+	)
+  )
+
+(member '(2) '((1) (2) (3)))
+
+(member '(4) '((1) (2) (3)))
+
+(define (memq a b) (member a b eq?))
+
+(memq 2 '(1 2 3))
+
+(memq 4 '(1 2 3))
+
+(memq '(2) '((1) (2) (3)))
+
+(define (_as a b t?)
+  (if (null? b)
+      #f
+    (if (t? a (caar b))
+	(car b)
+      (_as a (cdr b) t?)
+      )
+    )
+  )
+
+(define (assq a b) (_as a b eq?))
+(define (assoc a b) (_as a b equal?))
+
+(assq 'a '((a 1) (b 2) (c 3)))
+(assoc '(c) '((a 1) (b 2) ((c) 3)))
+
+(define string (lambda a (list->string a)))
+
+(define map
+  (lambda (a . b)
+	 (define (_a b)
+	   (cond ((null? b) ())
+		 (else
+		  (cons (caar b) (_a (cdr b)))
+		  )
+		 )
+	   )
+	 (define (_n b)
+	   (cond ((null? b) ())
+		 (else
+		  (cons (cdr (car b)) (_n (cdr b)))
+		  )
+		 )
+	   )
+	 (define (_d b)
+	   (cond ((null? (car b)) ())
+		 (else
+		  (cons (apply a (_a b)) (_d (_n b)))
+		  )
+		 )
+	   )
+	 (_d b)
+	 )
+  )
+
+(map cadr '((a b) (d e) (g h)))
+
+(define (newline) (write-char #\newline))
+
+(newline)
diff --git a/src/lambdakey-v1.0/ao_pins.h b/src/lambdakey-v1.0/ao_pins.h
index 2ba79c01..48b9db16 100644
--- a/src/lambdakey-v1.0/ao_pins.h
+++ b/src/lambdakey-v1.0/ao_pins.h
@@ -19,6 +19,9 @@
 #ifndef _AO_PINS_H_
 #define _AO_PINS_H_
 
+#define HAS_TASK	0
+#define HAS_AO_DELAY	1
+
 #define LED_PORT_ENABLE	STM_RCC_AHBENR_IOPBEN
 #define LED_PORT	(&stm_gpiob)
 #define LED_PIN_RED	4
diff --git a/src/lambdakey-v1.0/ao_scheme_os.h b/src/lambdakey-v1.0/ao_scheme_os.h
index a620684f..b3080f31 100644
--- a/src/lambdakey-v1.0/ao_scheme_os.h
+++ b/src/lambdakey-v1.0/ao_scheme_os.h
@@ -20,9 +20,8 @@
 
 #include "ao.h"
 
-#define AO_SCHEME_SAVE	1
-
-#define AO_SCHEME_POOL_TOTAL	2048
+#define AO_SCHEME_POOL		3584
+#define AO_SCHEME_TOKEN_MAX	64
 
 #ifndef __BYTE_ORDER
 #define	__LITTLE_ENDIAN	1234
diff --git a/src/lambdakey-v1.0/lambda.ld b/src/lambdakey-v1.0/lambda.ld
index 5de65eb5..b09fdb4a 100644
--- a/src/lambdakey-v1.0/lambda.ld
+++ b/src/lambdakey-v1.0/lambda.ld
@@ -17,10 +17,9 @@
  */
 
 MEMORY {
-	rom (rx) :   ORIGIN = 0x08001000, LENGTH = 25K
-	flash (r):   ORIGIN = 0x08007400, LENGTH = 3k
-	ram (!w) :   ORIGIN = 0x20000000, LENGTH = 6k - 128
-	stack (!w) : ORIGIN = 0x20000000 + 6k - 128, LENGTH = 128
+	rom (rx) :   ORIGIN = 0x08001000, LENGTH = 28K
+	ram (!w) :   ORIGIN = 0x20000000, LENGTH = 6k - 1k
+	stack (!w) : ORIGIN = 0x20000000 + 6k - 1k, LENGTH = 1k
 }
 
 INCLUDE registers.ld
@@ -93,9 +92,9 @@ SECTIONS {
 
 	/* Data -- relocated to RAM, but written to ROM
 	 */
-	.data : {
+	.data BLOCK(8): {
 		*(.data)	/* initialized data */
-		. = ALIGN(4);
+		. = ALIGN(8);
 		__data_end__ = .;
 	} >ram AT>rom
 
@@ -110,8 +109,6 @@ SECTIONS {
 	PROVIDE(end = .);
 
 	PROVIDE(__stack__ = ORIGIN(stack) + LENGTH(stack));
-
-	__flash__ = ORIGIN(flash);
 }
 
 ENTRY(start);
diff --git a/src/micropeak-v2.0/micropeak.ld b/src/micropeak-v2.0/micropeak.ld
index 77717e16..baeae5b8 100644
--- a/src/micropeak-v2.0/micropeak.ld
+++ b/src/micropeak-v2.0/micropeak.ld
@@ -19,8 +19,8 @@
 MEMORY {
 	rom (rx) :   ORIGIN = 0x08001000, LENGTH = 20K
 	flash(rx) :  ORIGIN = 0x08006000, LENGTH = 8K
-	ram (!w) :   ORIGIN = 0x20000000, LENGTH = 6k - 128
-	stack (!w) : ORIGIN = 0x20000000 + 6k - 128, LENGTH = 128
+	ram (!w) :   ORIGIN = 0x20000000, LENGTH = 6k - 512
+	stack (!w) : ORIGIN = 0x20000000 + 6k - 512, LENGTH = 512
 }
 
 INCLUDE registers.ld
@@ -94,11 +94,11 @@ SECTIONS {
 		*(.ramtext)
 	} >ram AT>rom
 
-	/* Data -- relocated to RAM, but written to ROM
+	/* Data -- relocated to RAM, but written to ROM,
+	 * also aligned to 8 bytes to agree with textram
 	 */
-	.data : {
+	.data BLOCK(8): {
 		*(.data)	/* initialized data */
-		. = ALIGN(4);
 		__data_end__ = .;
 	} >ram AT>rom
 
diff --git a/src/micropeak/Makefile b/src/micropeak/Makefile
index ac00f635..6e8cae14 100644
--- a/src/micropeak/Makefile
+++ b/src/micropeak/Makefile
@@ -103,7 +103,7 @@ ao_product.o: ao_product.c ao_product.h
 distclean:	clean
 
 clean:
-	rm -f *.o $(PROG) $(HEX) $(SCRIPT)
+	rm -f *.o *.elf *.ihx $(SCRIPT)
 	rm -f ao_product.h
 
 publish: $(PUBLISH_HEX) $(PUBLISH_SCRIPT)
diff --git a/src/scheme/Makefile b/src/scheme/Makefile
index dc36dde1..e600d5f7 100644
--- a/src/scheme/Makefile
+++ b/src/scheme/Makefile
@@ -1,12 +1,10 @@
-all: ao_scheme_builtin.h ao_scheme_const.h test/ao_scheme_test
+all: ao_scheme_builtin.h make-const/ao_scheme_make_const test/ao-scheme tiny-test/ao-scheme-tiny
 
 clean:
 	+cd make-const && make clean
 	+cd test && make clean
-	rm -f ao_scheme_const.h ao_scheme_builtin.h
-
-ao_scheme_const.h: ao_scheme_const.scheme make-const/ao_scheme_make_const
-	make-const/ao_scheme_make_const -o $@ ao_scheme_const.scheme
+	+cd tiny-test && make clean
+	rm -f ao_scheme_builtin.h
 
 ao_scheme_builtin.h: ao_scheme_make_builtin ao_scheme_builtin.txt
 	nickle ao_scheme_make_builtin ao_scheme_builtin.txt > $@
@@ -14,7 +12,10 @@ ao_scheme_builtin.h: ao_scheme_make_builtin ao_scheme_builtin.txt
 make-const/ao_scheme_make_const: FRC ao_scheme_builtin.h
 	+cd make-const && make ao_scheme_make_const
 
-test/ao_scheme_test: FRC ao_scheme_const.h ao_scheme_builtin.h
-	+cd test && make ao_scheme_test
+test/ao-scheme: FRC ao_scheme_builtin.h make-const/ao_scheme_make_const
+	+cd test && make
+
+tiny-test/ao-scheme-tiny: FRC ao_scheme_builtin.h make-const/ao_scheme_make_const
+	+cd tiny-test && make
 
 FRC:
diff --git a/src/scheme/ao_scheme.h b/src/scheme/ao_scheme.h
index 2fa1ed60..d4c9bc05 100644
--- a/src/scheme/ao_scheme.h
+++ b/src/scheme/ao_scheme.h
@@ -15,14 +15,26 @@
 #ifndef _AO_SCHEME_H_
 #define _AO_SCHEME_H_
 
+#ifndef DBG_MEM
 #define DBG_MEM		0
+#endif
+#ifndef DBG_EVAL
 #define DBG_EVAL	0
+#endif
+#ifndef DBG_READ
 #define DBG_READ	0
+#endif
+#ifndef DBG_FREE_CONS
 #define DBG_FREE_CONS	0
+#endif
 #define NDEBUG		1
 
 #include <stdint.h>
 #include <string.h>
+#include <stdbool.h>
+#define AO_SCHEME_BUILTIN_FEATURES
+#include "ao_scheme_builtin.h"
+#undef AO_SCHEME_BUILTIN_FEATURES
 #include <ao_scheme_os.h>
 #ifndef __BYTE_ORDER
 #include <endian.h>
@@ -40,6 +52,10 @@ struct ao_scheme_os_save {
 	uint16_t	const_checksum_inv;
 };
 
+#ifndef AO_SCHEME_POOL_TOTAL
+#error Must define AO_SCHEME_POOL_TOTAL for AO_SCHEME_SAVE
+#endif
+
 #define AO_SCHEME_POOL_EXTRA	(sizeof(struct ao_scheme_os_save))
 #define AO_SCHEME_POOL	((int) (AO_SCHEME_POOL_TOTAL - AO_SCHEME_POOL_EXTRA))
 
@@ -60,7 +76,7 @@ extern uint8_t ao_scheme_const[AO_SCHEME_POOL_CONST] __attribute__((aligned(4)))
 #define ao_scheme_pool ao_scheme_const
 #define AO_SCHEME_POOL AO_SCHEME_POOL_CONST
 
-#define _atom(n) ao_scheme_atom_poly(ao_scheme_atom_intern(n))
+#define _atom(n) ao_scheme_atom_poly(ao_scheme_atom_intern((char *) n))
 #define _bool(v) ao_scheme_bool_poly(ao_scheme_bool_get(v))
 
 #define _ao_scheme_bool_true	_bool(1)
@@ -75,7 +91,7 @@ extern uint8_t ao_scheme_const[AO_SCHEME_POOL_CONST] __attribute__((aligned(4)))
 #else
 #include "ao_scheme_const.h"
 #ifndef AO_SCHEME_POOL
-#define AO_SCHEME_POOL	3072
+#error Must define AO_SCHEME_POOL
 #endif
 #ifndef AO_SCHEME_POOL_EXTRA
 #define AO_SCHEME_POOL_EXTRA 0
@@ -86,7 +102,7 @@ extern uint8_t		ao_scheme_pool[AO_SCHEME_POOL + AO_SCHEME_POOL_EXTRA] __attribut
 /* Primitive types */
 #define AO_SCHEME_CONS		0
 #define AO_SCHEME_INT		1
-#define AO_SCHEME_STRING	2
+#define AO_SCHEME_BIGINT	2
 #define AO_SCHEME_OTHER		3
 
 #define AO_SCHEME_TYPE_MASK	0x0003
@@ -102,10 +118,20 @@ extern uint8_t		ao_scheme_pool[AO_SCHEME_POOL + AO_SCHEME_POOL_EXTRA] __attribut
 #define AO_SCHEME_LAMBDA	8
 #define AO_SCHEME_STACK		9
 #define AO_SCHEME_BOOL		10
-#define AO_SCHEME_BIGINT	11
+#define AO_SCHEME_STRING	11
+#ifdef AO_SCHEME_FEATURE_FLOAT
 #define AO_SCHEME_FLOAT		12
+#define _AO_SCHEME_FLOAT	AO_SCHEME_FLOAT
+#else
+#define _AO_SCHEME_FLOAT	12
+#endif
+#ifdef AO_SCHEME_FEATURE_VECTOR
 #define AO_SCHEME_VECTOR	13
-#define AO_SCHEME_NUM_TYPE	14
+#define _AO_SCHEME_VECTOR	AO_SCHEME_VECTOR
+#else
+#define _AO_SCHEME_VECTOR	_AO_SCHEME_FLOAT
+#endif
+#define AO_SCHEME_NUM_TYPE	(_AO_SCHEME_VECTOR+1)
 
 /* Leave two bits for types to use as they please */
 #define AO_SCHEME_OTHER_TYPE_MASK	0x3f
@@ -129,9 +155,17 @@ ao_scheme_is_const(ao_poly poly) {
 	return poly & AO_SCHEME_CONST;
 }
 
-#define AO_SCHEME_IS_CONST(a)	(ao_scheme_const <= ((uint8_t *) (a)) && ((uint8_t *) (a)) < ao_scheme_const + AO_SCHEME_POOL_CONST)
-#define AO_SCHEME_IS_POOL(a)	(ao_scheme_pool <= ((uint8_t *) (a)) && ((uint8_t *) (a)) < ao_scheme_pool + AO_SCHEME_POOL)
-#define AO_SCHEME_IS_INT(p)	(ao_scheme_poly_base_type(p) == AO_SCHEME_INT)
+static inline int
+ao_scheme_is_const_addr(const void *addr) {
+	const uint8_t *a = addr;
+	return (ao_scheme_const <= a) && (a < ao_scheme_const + AO_SCHEME_POOL_CONST);
+}
+
+static inline int
+ao_scheme_is_pool_addr(const void *addr) {
+	const uint8_t *a = addr;
+	return (ao_scheme_pool <= a) && (a < ao_scheme_pool + AO_SCHEME_POOL);
+}
 
 void *
 ao_scheme_ref(ao_poly poly);
@@ -158,6 +192,11 @@ struct ao_scheme_atom {
 	char		name[];
 };
 
+struct ao_scheme_string {
+	uint8_t		type;
+	char		val[];
+};
+
 struct ao_scheme_val {
 	ao_poly		atom;
 	ao_poly		val;
@@ -182,54 +221,41 @@ struct ao_scheme_bool {
 	uint16_t		pad;
 };
 
-struct ao_scheme_bigint {
-	uint32_t		value;
-};
 
+#ifdef AO_SCHEME_FEATURE_FLOAT
 struct ao_scheme_float {
 	uint8_t			type;
 	uint8_t			pad1;
 	uint16_t		pad2;
 	float			value;
 };
+#endif
 
+#ifdef AO_SCHEME_FEATURE_VECTOR
 struct ao_scheme_vector {
 	uint8_t			type;
 	uint8_t			pad1;
 	uint16_t		length;
 	ao_poly			vals[];
 };
-
-#if __BYTE_ORDER == __LITTLE_ENDIAN
-static inline uint32_t
-ao_scheme_int_bigint(int32_t i) {
-	return AO_SCHEME_BIGINT | (i << 8);
-}
-static inline int32_t
-ao_scheme_bigint_int(uint32_t bi) {
-	return (int32_t) bi >> 8;
-}
-#else
-static inline uint32_t
-ao_scheme_int_bigint(int32_t i) {
-	return (uint32_t) (i & 0xffffff) | (AO_SCHEME_BIGINT << 24);
-}
-static inlint int32_t
-ao_scheme_bigint_int(uint32_t bi) {
-	return (int32_t) (bi << 8) >> 8;
-}
 #endif
 
 #define AO_SCHEME_MIN_INT	(-(1 << (15 - AO_SCHEME_TYPE_SHIFT)))
 #define AO_SCHEME_MAX_INT	((1 << (15 - AO_SCHEME_TYPE_SHIFT)) - 1)
-#define AO_SCHEME_MIN_BIGINT	(-(1 << 24))
-#define AO_SCHEME_MAX_BIGINT	((1 << 24) - 1)
 
-#define AO_SCHEME_NOT_INTEGER	0x7fffffff
+#ifdef AO_SCHEME_FEATURE_BIGINT
+
+struct ao_scheme_bigint {
+	uint32_t		value;
+};
+
+#define AO_SCHEME_MIN_BIGINT	INT32_MIN
+#define AO_SCHEME_MAX_BIGINT	INT32_MAX
+
+#endif	/* AO_SCHEME_FEATURE_BIGINT */
 
 /* Set on type when the frame escapes the lambda */
 #define AO_SCHEME_FRAME_MARK	0x80
-#define AO_SCHEME_FRAME_PRINT	0x40
 
 static inline int ao_scheme_frame_marked(struct ao_scheme_frame *f) {
 	return f->type & AO_SCHEME_FRAME_MARK;
@@ -281,7 +307,6 @@ struct ao_scheme_stack {
 };
 
 #define AO_SCHEME_STACK_MARK	0x80	/* set on type when a reference has been taken */
-#define AO_SCHEME_STACK_PRINT	0x40	/* stack is being printed */
 
 static inline int ao_scheme_stack_marked(struct ao_scheme_stack *s) {
 	return s->type & AO_SCHEME_STACK_MARK;
@@ -433,6 +458,7 @@ ao_scheme_int_poly(int32_t i)
 	return ((ao_poly) i << 2) | AO_SCHEME_INT;
 }
 
+#ifdef AO_SCHEME_FEATURE_BIGINT
 static inline struct ao_scheme_bigint *
 ao_scheme_poly_bigint(ao_poly poly)
 {
@@ -442,19 +468,20 @@ ao_scheme_poly_bigint(ao_poly poly)
 static inline ao_poly
 ao_scheme_bigint_poly(struct ao_scheme_bigint *bi)
 {
-	return ao_scheme_poly(bi, AO_SCHEME_OTHER);
+	return ao_scheme_poly(bi, AO_SCHEME_BIGINT);
 }
+#endif /* AO_SCHEME_FEATURE_BIGINT */
 
-static inline char *
+static inline struct ao_scheme_string *
 ao_scheme_poly_string(ao_poly poly)
 {
 	return ao_scheme_ref(poly);
 }
 
 static inline ao_poly
-ao_scheme_string_poly(char *s)
+ao_scheme_string_poly(struct ao_scheme_string *s)
 {
-	return ao_scheme_poly(s, AO_SCHEME_STRING);
+	return ao_scheme_poly(s, AO_SCHEME_OTHER);
 }
 
 static inline struct ao_scheme_atom *
@@ -493,6 +520,7 @@ ao_scheme_poly_bool(ao_poly poly)
 	return ao_scheme_ref(poly);
 }
 
+#ifdef AO_SCHEME_FEATURE_FLOAT
 static inline ao_poly
 ao_scheme_float_poly(struct ao_scheme_float *f)
 {
@@ -507,7 +535,9 @@ ao_scheme_poly_float(ao_poly poly)
 
 float
 ao_scheme_poly_number(ao_poly p);
+#endif
 
+#ifdef AO_SCHEME_FEATURE_VECTOR
 static inline ao_poly
 ao_scheme_vector_poly(struct ao_scheme_vector *v)
 {
@@ -519,6 +549,7 @@ ao_scheme_poly_vector(ao_poly poly)
 {
 	return ao_scheme_ref(poly);
 }
+#endif
 
 /* memory functions */
 
@@ -528,19 +559,8 @@ extern uint64_t ao_scheme_loops[2];
 
 /* returns 1 if the object was already marked */
 int
-ao_scheme_mark(const struct ao_scheme_type *type, void *addr);
-
-/* returns 1 if the object was already marked */
-int
 ao_scheme_mark_memory(const struct ao_scheme_type *type, void *addr);
 
-void *
-ao_scheme_move_map(void *addr);
-
-/* returns 1 if the object was already moved */
-int
-ao_scheme_move(const struct ao_scheme_type *type, void **ref);
-
 /* returns 1 if the object was already moved */
 int
 ao_scheme_move_memory(const struct ao_scheme_type *type, void **ref);
@@ -548,6 +568,21 @@ ao_scheme_move_memory(const struct ao_scheme_type *type, void **ref);
 void *
 ao_scheme_alloc(int size);
 
+/* Marks an object as being printed, returns 1 if it was already marked */
+int
+ao_scheme_print_mark_addr(void *addr);
+
+void
+ao_scheme_print_clear_addr(void *addr);
+
+/* Notes that printing has started */
+void
+ao_scheme_print_start(void);
+
+/* Notes that printing has ended, returns 1 if printing is still happening */
+int
+ao_scheme_print_stop(void);
+
 #define AO_SCHEME_COLLECT_FULL		1
 #define AO_SCHEME_COLLECT_INCREMENTAL	0
 
@@ -560,48 +595,82 @@ ao_scheme_cons_check(struct ao_scheme_cons *cons);
 #endif
 
 void
-ao_scheme_cons_stash(int id, struct ao_scheme_cons *cons);
+ao_scheme_poly_stash(ao_poly poly);
 
-struct ao_scheme_cons *
-ao_scheme_cons_fetch(int id);
+ao_poly
+ao_scheme_poly_fetch(void);
 
-void
-ao_scheme_poly_stash(int id, ao_poly poly);
+static inline void
+ao_scheme_cons_stash(struct ao_scheme_cons *cons) {
+	ao_scheme_poly_stash(ao_scheme_cons_poly(cons));
+}
 
-ao_poly
-ao_scheme_poly_fetch(int id);
+static inline struct ao_scheme_cons *
+ao_scheme_cons_fetch(void) {
+	return ao_scheme_poly_cons(ao_scheme_poly_fetch());
+}
 
-void
-ao_scheme_string_stash(int id, char *string);
+static inline void
+ao_scheme_atom_stash(struct ao_scheme_atom *atom) {
+	ao_scheme_poly_stash(ao_scheme_atom_poly(atom));
+}
 
-char *
-ao_scheme_string_fetch(int id);
+static inline struct ao_scheme_atom *
+ao_scheme_atom_fetch(void) {
+	return ao_scheme_poly_atom(ao_scheme_poly_fetch());
+}
 
 static inline void
-ao_scheme_stack_stash(int id, struct ao_scheme_stack *stack) {
-	ao_scheme_poly_stash(id, ao_scheme_stack_poly(stack));
+ao_scheme_string_stash(struct ao_scheme_string *string) {
+	ao_scheme_poly_stash(ao_scheme_string_poly(string));
+}
+
+static inline struct ao_scheme_string *
+ao_scheme_string_fetch(void) {
+	return ao_scheme_poly_string(ao_scheme_poly_fetch());
+}
+
+#ifdef AO_SCHEME_FEATURE_VECTOR
+static inline void
+ao_scheme_vector_stash(struct ao_scheme_vector *vector) {
+	ao_scheme_poly_stash(ao_scheme_vector_poly(vector));
+}
+
+static inline struct ao_scheme_vector *
+ao_scheme_vector_fetch(void) {
+	return ao_scheme_poly_vector(ao_scheme_poly_fetch());
+}
+#endif
+
+static inline void
+ao_scheme_stack_stash(struct ao_scheme_stack *stack) {
+	ao_scheme_poly_stash(ao_scheme_stack_poly(stack));
 }
 
 static inline struct ao_scheme_stack *
-ao_scheme_stack_fetch(int id) {
-	return ao_scheme_poly_stack(ao_scheme_poly_fetch(id));
+ao_scheme_stack_fetch(void) {
+	return ao_scheme_poly_stack(ao_scheme_poly_fetch());
 }
 
-void
-ao_scheme_frame_stash(int id, struct ao_scheme_frame *frame);
+static inline void
+ao_scheme_frame_stash(struct ao_scheme_frame *frame) {
+	ao_scheme_poly_stash(ao_scheme_frame_poly(frame));
+}
 
-struct ao_scheme_frame *
-ao_scheme_frame_fetch(int id);
+static inline struct ao_scheme_frame *
+ao_scheme_frame_fetch(void) {
+	return ao_scheme_poly_frame(ao_scheme_poly_fetch());
+}
 
 /* bool */
 
 extern const struct ao_scheme_type ao_scheme_bool_type;
 
 void
-ao_scheme_bool_write(ao_poly v);
+ao_scheme_bool_write(ao_poly v, bool write);
 
 #ifdef AO_SCHEME_MAKE_CONST
-struct ao_scheme_bool	*ao_scheme_true, *ao_scheme_false;
+extern struct ao_scheme_bool	*ao_scheme_true, *ao_scheme_false;
 
 struct ao_scheme_bool *
 ao_scheme_bool_get(uint8_t value);
@@ -618,7 +687,7 @@ struct ao_scheme_cons *
 ao_scheme_cons_cdr(struct ao_scheme_cons *cons);
 
 ao_poly
-ao_scheme__cons(ao_poly car, ao_poly cdr);
+ao_scheme_cons(ao_poly car, ao_poly cdr);
 
 extern struct ao_scheme_cons *ao_scheme_cons_free_list;
 
@@ -626,10 +695,7 @@ void
 ao_scheme_cons_free(struct ao_scheme_cons *cons);
 
 void
-ao_scheme_cons_write(ao_poly);
-
-void
-ao_scheme_cons_display(ao_poly);
+ao_scheme_cons_write(ao_poly, bool write);
 
 int
 ao_scheme_cons_length(struct ao_scheme_cons *cons);
@@ -640,23 +706,26 @@ ao_scheme_cons_copy(struct ao_scheme_cons *cons);
 /* string */
 extern const struct ao_scheme_type ao_scheme_string_type;
 
-char *
-ao_scheme_string_copy(char *a);
+struct ao_scheme_string *
+ao_scheme_string_copy(struct ao_scheme_string *a);
 
-char *
-ao_scheme_string_cat(char *a, char *b);
+struct ao_scheme_string *
+ao_scheme_string_make(char *a);
+
+struct ao_scheme_string *
+ao_scheme_atom_to_string(struct ao_scheme_atom *a);
+
+struct ao_scheme_string *
+ao_scheme_string_cat(struct ao_scheme_string *a, struct ao_scheme_string *b);
 
 ao_poly
 ao_scheme_string_pack(struct ao_scheme_cons *cons);
 
 ao_poly
-ao_scheme_string_unpack(char *a);
+ao_scheme_string_unpack(struct ao_scheme_string *a);
 
 void
-ao_scheme_string_write(ao_poly s);
-
-void
-ao_scheme_string_display(ao_poly s);
+ao_scheme_string_write(ao_poly s, bool write);
 
 /* atom */
 extern const struct ao_scheme_type ao_scheme_atom_type;
@@ -666,7 +735,10 @@ extern struct ao_scheme_frame	*ao_scheme_frame_global;
 extern struct ao_scheme_frame	*ao_scheme_frame_current;
 
 void
-ao_scheme_atom_write(ao_poly a);
+ao_scheme_atom_write(ao_poly a, bool write);
+
+struct ao_scheme_atom *
+ao_scheme_string_to_atom(struct ao_scheme_string *string);
 
 struct ao_scheme_atom *
 ao_scheme_atom_intern(char *name);
@@ -685,10 +757,11 @@ ao_scheme_atom_def(ao_poly atom, ao_poly val);
 
 /* int */
 void
-ao_scheme_int_write(ao_poly i);
+ao_scheme_int_write(ao_poly i, bool write);
 
+#ifdef AO_SCHEME_FEATURE_BIGINT
 int32_t
-ao_scheme_poly_integer(ao_poly p);
+ao_scheme_poly_integer(ao_poly p, bool *fail);
 
 ao_poly
 ao_scheme_integer_poly(int32_t i);
@@ -700,17 +773,27 @@ ao_scheme_integer_typep(uint8_t t)
 }
 
 void
-ao_scheme_bigint_write(ao_poly i);
+ao_scheme_bigint_write(ao_poly i, bool write);
 
 extern const struct ao_scheme_type	ao_scheme_bigint_type;
 
-/* vector */
+#else
 
-void
-ao_scheme_vector_write(ao_poly v);
+#define ao_scheme_poly_integer(a,b) ao_scheme_poly_int(a)
+#define ao_scheme_integer_poly ao_scheme_int_poly
+
+static inline int
+ao_scheme_integer_typep(uint8_t t)
+{
+	return (t == AO_SCHEME_INT);
+}
+
+#endif /* AO_SCHEME_FEATURE_BIGINT */
+
+/* vector */
 
 void
-ao_scheme_vector_display(ao_poly v);
+ao_scheme_vector_write(ao_poly v, bool write);
 
 struct ao_scheme_vector *
 ao_scheme_vector_alloc(uint16_t length, ao_poly fill);
@@ -730,11 +813,10 @@ ao_scheme_vector_to_list(struct ao_scheme_vector *vector);
 extern const struct ao_scheme_type	ao_scheme_vector_type;
 
 /* prim */
-void
-ao_scheme_poly_write(ao_poly p);
+void (*ao_scheme_poly_write_func(ao_poly p))(ao_poly p, bool write);
 
-void
-ao_scheme_poly_display(ao_poly p);
+static inline void
+ao_scheme_poly_write(ao_poly p, bool write) { (*ao_scheme_poly_write_func(p))(p, write); }
 
 int
 ao_scheme_poly_mark(ao_poly p, uint8_t note_cons);
@@ -758,26 +840,29 @@ ao_poly
 ao_scheme_set_cond(struct ao_scheme_cons *cons);
 
 /* float */
+#ifdef AO_SCHEME_FEATURE_FLOAT
 extern const struct ao_scheme_type ao_scheme_float_type;
 
 void
-ao_scheme_float_write(ao_poly p);
+ao_scheme_float_write(ao_poly p, bool write);
 
 ao_poly
 ao_scheme_float_get(float value);
+#endif
 
+#ifdef AO_SCHEME_FEATURE_FLOAT
 static inline uint8_t
 ao_scheme_number_typep(uint8_t t)
 {
 	return ao_scheme_integer_typep(t) || (t == AO_SCHEME_FLOAT);
 }
-
-float
-ao_scheme_poly_number(ao_poly p);
+#else
+#define ao_scheme_number_typep ao_scheme_integer_typep
+#endif
 
 /* builtin */
 void
-ao_scheme_builtin_write(ao_poly b);
+ao_scheme_builtin_write(ao_poly b, bool write);
 
 extern const struct ao_scheme_type ao_scheme_builtin_type;
 
@@ -836,7 +921,7 @@ ao_poly
 ao_scheme_frame_add(struct ao_scheme_frame *frame, ao_poly atom, ao_poly val);
 
 void
-ao_scheme_frame_write(ao_poly p);
+ao_scheme_frame_write(ao_poly p, bool write);
 
 void
 ao_scheme_frame_init(void);
@@ -850,7 +935,7 @@ struct ao_scheme_lambda *
 ao_scheme_lambda_new(ao_poly cons);
 
 void
-ao_scheme_lambda_write(ao_poly lambda);
+ao_scheme_lambda_write(ao_poly lambda, bool write);
 
 ao_poly
 ao_scheme_lambda_eval(void);
@@ -861,6 +946,8 @@ extern const struct ao_scheme_type ao_scheme_stack_type;
 extern struct ao_scheme_stack	*ao_scheme_stack;
 extern struct ao_scheme_stack	*ao_scheme_stack_free_list;
 
+extern int			ao_scheme_frame_print_indent;
+
 void
 ao_scheme_stack_reset(struct ao_scheme_stack *stack);
 
@@ -874,7 +961,7 @@ void
 ao_scheme_stack_clear(void);
 
 void
-ao_scheme_stack_write(ao_poly stack);
+ao_scheme_stack_write(ao_poly stack, bool write);
 
 ao_poly
 ao_scheme_stack_eval(void);
@@ -882,19 +969,13 @@ ao_scheme_stack_eval(void);
 /* error */
 
 void
-ao_scheme_vprintf(char *format, va_list args);
+ao_scheme_vprintf(const char *format, va_list args);
 
 void
-ao_scheme_printf(char *format, ...);
-
-void
-ao_scheme_error_poly(char *name, ao_poly poly, ao_poly last);
-
-void
-ao_scheme_error_frame(int indent, char *name, struct ao_scheme_frame *frame);
+ao_scheme_printf(const char *format, ...);
 
 ao_poly
-ao_scheme_error(int error, char *format, ...);
+ao_scheme_error(int error, const char *format, ...);
 
 /* builtins */
 
@@ -903,9 +984,11 @@ ao_scheme_error(int error, char *format, ...);
 
 /* debugging macros */
 
-#if DBG_EVAL || DBG_READ || DBG_MEM
-#define DBG_CODE	1
+#if DBG_EVAL || DBG_READ
 int ao_scheme_stack_depth;
+#endif
+
+#if DBG_EVAL
 #define DBG_DO(a)	a
 #define DBG_INDENT()	do { int _s; for(_s = 0; _s < ao_scheme_stack_depth; _s++) printf("  "); } while(0)
 #define DBG_IN()	(++ao_scheme_stack_depth)
@@ -913,10 +996,10 @@ int ao_scheme_stack_depth;
 #define DBG_RESET()	(ao_scheme_stack_depth = 0)
 #define DBG(...) 	ao_scheme_printf(__VA_ARGS__)
 #define DBGI(...)	do { printf("%4d: ", __LINE__); DBG_INDENT(); DBG(__VA_ARGS__); } while (0)
-#define DBG_CONS(a)	ao_scheme_cons_write(ao_scheme_cons_poly(a))
-#define DBG_POLY(a)	ao_scheme_poly_write(a)
+#define DBG_CONS(a)	ao_scheme_cons_write(ao_scheme_cons_poly(a), true)
+#define DBG_POLY(a)	ao_scheme_poly_write(a, true)
 #define OFFSET(a)	((a) ? (int) ((uint8_t *) a - ao_scheme_pool) : -1)
-#define DBG_STACK()	ao_scheme_stack_write(ao_scheme_stack_poly(ao_scheme_stack))
+#define DBG_STACK()	ao_scheme_stack_write(ao_scheme_stack_poly(ao_scheme_stack), true)
 static inline void
 ao_scheme_frames_dump(void)
 {
@@ -942,27 +1025,46 @@ ao_scheme_frames_dump(void)
 #endif
 
 #if DBG_READ
-#define RDBGI(...)	DBGI(__VA_ARGS__)
-#define RDBG_IN()	DBG_IN()
-#define RDBG_OUT()	DBG_OUT()
+#define RDBGI(...)	do { printf("%4d: ", __LINE__); DBG_INDENT(); ao_scheme_printf(__VA_ARGS__); } while (0)
+#define RDBG_IN()	(++ao_scheme_stack_depth)
+#define RDBG_OUT()	(--ao_scheme_stack_depth)
 #else
 #define RDBGI(...)
 #define RDBG_IN()
 #define RDBG_OUT()
 #endif
 
-#define DBG_MEM_START	1
+static inline int
+ao_scheme_mdbg_offset(void *a)
+{
+	uint8_t		*u = a;
+
+	if (u == 0)
+		return -1;
+
+	if (ao_scheme_pool <= u && u < ao_scheme_pool + AO_SCHEME_POOL)
+		return u - ao_scheme_pool;
+
+#ifndef AO_SCHEME_MAKE_CONST
+	if (ao_scheme_const <= u && u < ao_scheme_const + AO_SCHEME_POOL_CONST)
+		return - (int) (u - ao_scheme_const);
+#endif
+	return -2;
+}
+
+#define MDBG_OFFSET(a)	ao_scheme_mdbg_offset(a)
 
 #if DBG_MEM
 
+#define DBG_MEM_START	1
+
 #include <assert.h>
 extern int dbg_move_depth;
 #define MDBG_DUMP 1
-#define MDBG_OFFSET(a)	((a) ? (int) ((uint8_t *) (a) - ao_scheme_pool) : -1)
 
 extern int dbg_mem;
 
-#define MDBG_DO(a)	DBG_DO(a)
+#define MDBG_DO(a)	a
 #define MDBG_MOVE(...) do { if (dbg_mem) { int d; for (d = 0; d < dbg_move_depth; d++) printf ("  "); printf(__VA_ARGS__); } } while (0)
 #define MDBG_MORE(...) do { if (dbg_mem) printf(__VA_ARGS__); } while (0)
 #define MDBG_MOVE_IN()	(dbg_move_depth++)
diff --git a/src/scheme/ao_scheme_atom.c b/src/scheme/ao_scheme_atom.c
index cb32b7fe..c72a2b27 100644
--- a/src/scheme/ao_scheme_atom.c
+++ b/src/scheme/ao_scheme_atom.c
@@ -71,8 +71,8 @@ const struct ao_scheme_type ao_scheme_atom_type = {
 
 struct ao_scheme_atom	*ao_scheme_atoms;
 
-struct ao_scheme_atom *
-ao_scheme_atom_intern(char *name)
+static struct ao_scheme_atom *
+ao_scheme_atom_find(char *name)
 {
 	struct ao_scheme_atom	*atom;
 
@@ -86,15 +86,43 @@ ao_scheme_atom_intern(char *name)
 			return atom;
 	}
 #endif
-	ao_scheme_string_stash(0, name);
-	atom = ao_scheme_alloc(name_size(name));
-	name = ao_scheme_string_fetch(0);
+	return NULL;
+}
+
+static void
+ao_scheme_atom_init(struct ao_scheme_atom *atom, char *name)
+{
 	if (atom) {
 		atom->type = AO_SCHEME_ATOM;
+		strcpy(atom->name, name);
 		atom->next = ao_scheme_atom_poly(ao_scheme_atoms);
 		ao_scheme_atoms = atom;
-		strcpy(atom->name, name);
 	}
+}
+
+struct ao_scheme_atom *
+ao_scheme_string_to_atom(struct ao_scheme_string *string)
+{
+	struct ao_scheme_atom	*atom = ao_scheme_atom_find(string->val);
+
+	if (atom)
+		return atom;
+	ao_scheme_string_stash(string);
+	atom = ao_scheme_alloc(name_size(string->val));
+	string = ao_scheme_string_fetch();
+	ao_scheme_atom_init(atom, string->val);
+	return atom;
+}
+
+struct ao_scheme_atom *
+ao_scheme_atom_intern(char *name)
+{
+	struct ao_scheme_atom	*atom = ao_scheme_atom_find(name);
+	if (atom)
+		return atom;
+
+	atom = ao_scheme_alloc(name_size(name));
+	ao_scheme_atom_init(atom, name);
 	return atom;
 }
 
@@ -160,8 +188,9 @@ ao_scheme_atom_def(ao_poly atom, ao_poly val)
 }
 
 void
-ao_scheme_atom_write(ao_poly a)
+ao_scheme_atom_write(ao_poly a, bool write)
 {
 	struct ao_scheme_atom *atom = ao_scheme_poly_atom(a);
+	(void) write;
 	printf("%s", atom->name);
 }
diff --git a/src/scheme/ao_scheme_bool.c b/src/scheme/ao_scheme_bool.c
index c1e880ca..88970667 100644
--- a/src/scheme/ao_scheme_bool.c
+++ b/src/scheme/ao_scheme_bool.c
@@ -38,10 +38,11 @@ const struct ao_scheme_type ao_scheme_bool_type = {
 };
 
 void
-ao_scheme_bool_write(ao_poly v)
+ao_scheme_bool_write(ao_poly v, bool write)
 {
 	struct ao_scheme_bool	*b = ao_scheme_poly_bool(v);
 
+	(void) write;
 	if (b->value)
 		printf("#t");
 	else
diff --git a/src/scheme/ao_scheme_builtin.c b/src/scheme/ao_scheme_builtin.c
index 1754e677..81fd9010 100644
--- a/src/scheme/ao_scheme_builtin.c
+++ b/src/scheme/ao_scheme_builtin.c
@@ -52,7 +52,7 @@ char *ao_scheme_args_name(uint8_t args) {
 	case AO_SCHEME_FUNC_LAMBDA: return ao_scheme_poly_atom(_ao_scheme_atom_lambda)->name;
 	case AO_SCHEME_FUNC_NLAMBDA: return ao_scheme_poly_atom(_ao_scheme_atom_nlambda)->name;
 	case AO_SCHEME_FUNC_MACRO: return ao_scheme_poly_atom(_ao_scheme_atom_macro)->name;
-	default: return "???";
+	default: return (char *) "???";
 	}
 }
 #else
@@ -64,7 +64,7 @@ static char *
 ao_scheme_builtin_name(enum ao_scheme_builtin_id b) {
 	if (b < _builtin_last)
 		return ao_scheme_poly_atom(builtin_names[b])->name;
-	return "???";
+	return (char *) "???";
 }
 
 static const ao_poly ao_scheme_args_atoms[] = {
@@ -79,14 +79,15 @@ ao_scheme_args_name(uint8_t args)
 	args &= AO_SCHEME_FUNC_MASK;
 	if (args < sizeof ao_scheme_args_atoms / sizeof ao_scheme_args_atoms[0])
 		return ao_scheme_poly_atom(ao_scheme_args_atoms[args])->name;
-	return "(unknown)";
+	return (char *) "(unknown)";
 }
 #endif
 
 void
-ao_scheme_builtin_write(ao_poly b)
+ao_scheme_builtin_write(ao_poly b, bool write)
 {
 	struct ao_scheme_builtin *builtin = ao_scheme_poly_builtin(b);
+	(void) write;
 	printf("%s", ao_scheme_builtin_name(builtin->func));
 }
 
@@ -127,13 +128,14 @@ ao_scheme_check_argt(ao_poly name, struct ao_scheme_cons *cons, int argc, int ty
 	return _ao_scheme_bool_true;
 }
 
-int32_t
+static int32_t
 ao_scheme_arg_int(ao_poly name, struct ao_scheme_cons *cons, int argc)
 {
-	ao_poly p = ao_scheme_arg(cons, argc);
-	int32_t	i = ao_scheme_poly_integer(p);
+	ao_poly 	p = ao_scheme_arg(cons, argc);
+	bool		fail = false;
+	int32_t		i = ao_scheme_poly_integer(p, &fail);
 
-	if (i == AO_SCHEME_NOT_INTEGER)
+	if (fail)
 		(void) ao_scheme_error(AO_SCHEME_INVALID, "%v: arg %d invalid type %v", name, argc, p);
 	return i;
 }
@@ -166,7 +168,7 @@ ao_scheme_do_cons(struct ao_scheme_cons *cons)
 		return AO_SCHEME_NIL;
 	car = ao_scheme_arg(cons, 0);
 	cdr = ao_scheme_arg(cons, 1);
-	return ao_scheme__cons(car, cdr);
+	return ao_scheme_cons(car, cdr);
 }
 
 ao_poly
@@ -251,10 +253,10 @@ ao_scheme_do_setq(struct ao_scheme_cons *cons)
 		return ao_scheme_error(AO_SCHEME_INVALID, "set! of non-atom %v", name);
 	if (!ao_scheme_atom_ref(name, NULL))
 		return ao_scheme_error(AO_SCHEME_INVALID, "atom %v not defined", name);
-	return ao_scheme__cons(_ao_scheme_atom_set,
-			     ao_scheme__cons(ao_scheme__cons(_ao_scheme_atom_quote,
-							 ao_scheme__cons(name, AO_SCHEME_NIL)),
-					   cons->cdr));
+	return ao_scheme_cons(_ao_scheme_atom_set,
+			      ao_scheme_cons(ao_scheme_cons(_ao_scheme_atom_quote,
+							    ao_scheme_cons(name, AO_SCHEME_NIL)),
+					     cons->cdr));
 }
 
 ao_poly
@@ -286,7 +288,7 @@ ao_scheme_do_write(struct ao_scheme_cons *cons)
 	ao_poly	val = AO_SCHEME_NIL;
 	while (cons) {
 		val = cons->car;
-		ao_scheme_poly_write(val);
+		ao_scheme_poly_write(val, true);
 		cons = ao_scheme_cons_cdr(cons);
 		if (cons)
 			printf(" ");
@@ -300,16 +302,16 @@ ao_scheme_do_display(struct ao_scheme_cons *cons)
 	ao_poly	val = AO_SCHEME_NIL;
 	while (cons) {
 		val = cons->car;
-		ao_scheme_poly_display(val);
+		ao_scheme_poly_write(val, false);
 		cons = ao_scheme_cons_cdr(cons);
 	}
 	return _ao_scheme_bool_true;
 }
 
-ao_poly
+static ao_poly
 ao_scheme_math(struct ao_scheme_cons *orig_cons, enum ao_scheme_builtin_id op)
 {
-	struct ao_scheme_cons *cons = cons;
+	struct ao_scheme_cons *cons;
 	ao_poly	ret = AO_SCHEME_NIL;
 
 	for (cons = orig_cons; cons; cons = ao_scheme_cons_cdr(cons)) {
@@ -319,55 +321,74 @@ ao_scheme_math(struct ao_scheme_cons *orig_cons, enum ao_scheme_builtin_id op)
 
 		if (cons == orig_cons) {
 			ret = car;
-			ao_scheme_cons_stash(0, cons);
+			ao_scheme_cons_stash(cons);
 			if (cons->cdr == AO_SCHEME_NIL) {
 				switch (op) {
 				case builtin_minus:
 					if (ao_scheme_integer_typep(ct))
-						ret = ao_scheme_integer_poly(-ao_scheme_poly_integer(ret));
+						ret = ao_scheme_integer_poly(-ao_scheme_poly_integer(ret, NULL));
+#ifdef AO_SCHEME_FEATURE_FLOAT
 					else if (ct == AO_SCHEME_FLOAT)
 						ret = ao_scheme_float_get(-ao_scheme_poly_number(ret));
+#endif
 					break;
 				case builtin_divide:
-					if (ao_scheme_integer_typep(ct) && ao_scheme_poly_integer(ret) == 1)
-						;
-					else if (ao_scheme_number_typep(ct)) {
-						float	v = ao_scheme_poly_number(ret);
-						ret = ao_scheme_float_get(1/v);
+					if (ao_scheme_poly_integer(ret, NULL) == 1) {
+					} else {
+#ifdef AO_SCHEME_FEATURE_FLOAT
+						if (ao_scheme_number_typep(ct)) {
+							float	v = ao_scheme_poly_number(ret);
+							ret = ao_scheme_float_get(1/v);
+						}
+#else
+						ret = ao_scheme_integer_poly(0);
+#endif
 					}
 					break;
 				default:
 					break;
 				}
 			}
-			cons = ao_scheme_cons_fetch(0);
+			cons = ao_scheme_cons_fetch();
 		} else if (ao_scheme_integer_typep(rt) && ao_scheme_integer_typep(ct)) {
-			int32_t	r = ao_scheme_poly_integer(ret);
-			int32_t	c = ao_scheme_poly_integer(car);
+			int32_t	r = ao_scheme_poly_integer(ret, NULL);
+			int32_t	c = ao_scheme_poly_integer(car, NULL);
+#ifdef AO_SCHEME_FEATURE_FLOAT
 			int64_t t;
+#endif
 
 			switch(op) {
 			case builtin_plus:
 				r += c;
 			check_overflow:
+#ifdef AO_SCHEME_FEATURE_FLOAT
 				if (r < AO_SCHEME_MIN_BIGINT || AO_SCHEME_MAX_BIGINT < r)
 					goto inexact;
+#endif
 				break;
 			case builtin_minus:
 				r -= c;
 				goto check_overflow;
 				break;
 			case builtin_times:
+#ifdef AO_SCHEME_FEATURE_FLOAT
 				t = (int64_t) r * (int64_t) c;
 				if (t < AO_SCHEME_MIN_BIGINT || AO_SCHEME_MAX_BIGINT < t)
 					goto inexact;
 				r = (int32_t) t;
+#else
+				r = r * c;
+#endif
 				break;
 			case builtin_divide:
+#ifdef AO_SCHEME_FEATURE_FLOAT
 				if (c != 0 && (r % c) == 0)
 					r /= c;
 				else
 					goto inexact;
+#else
+				r /= c;
+#endif
 				break;
 			case builtin_quotient:
 				if (c == 0)
@@ -392,9 +413,10 @@ ao_scheme_math(struct ao_scheme_cons *orig_cons, enum ao_scheme_builtin_id op)
 			default:
 				break;
 			}
-			ao_scheme_cons_stash(0, cons);
+			ao_scheme_cons_stash(cons);
 			ret = ao_scheme_integer_poly(r);
-			cons = ao_scheme_cons_fetch(0);
+			cons = ao_scheme_cons_fetch();
+#ifdef AO_SCHEME_FEATURE_FLOAT
 		} else if (ao_scheme_number_typep(rt) && ao_scheme_number_typep(ct)) {
 			float r, c;
 		inexact:
@@ -420,15 +442,16 @@ ao_scheme_math(struct ao_scheme_cons *orig_cons, enum ao_scheme_builtin_id op)
 			default:
 				break;
 			}
-			ao_scheme_cons_stash(0, cons);
+			ao_scheme_cons_stash(cons);
 			ret = ao_scheme_float_get(r);
-			cons = ao_scheme_cons_fetch(0);
+			cons = ao_scheme_cons_fetch();
+#endif
 		}
 		else if (rt == AO_SCHEME_STRING && ct == AO_SCHEME_STRING && op == builtin_plus) {
-			ao_scheme_cons_stash(0, cons);
+			ao_scheme_cons_stash(cons);
 			ret = ao_scheme_string_poly(ao_scheme_string_cat(ao_scheme_poly_string(ret),
 									 ao_scheme_poly_string(car)));
-			cons = ao_scheme_cons_fetch(0);
+			cons = ao_scheme_cons_fetch();
 			if (!ret)
 				return ret;
 		}
@@ -480,7 +503,7 @@ ao_scheme_do_remainder(struct ao_scheme_cons *cons)
 	return ao_scheme_math(cons, builtin_remainder);
 }
 
-ao_poly
+static ao_poly
 ao_scheme_compare(struct ao_scheme_cons *cons, enum ao_scheme_builtin_id op)
 {
 	ao_poly	left;
@@ -498,8 +521,8 @@ ao_scheme_compare(struct ao_scheme_cons *cons, enum ao_scheme_builtin_id op)
 			uint8_t	lt = ao_scheme_poly_type(left);
 			uint8_t	rt = ao_scheme_poly_type(right);
 			if (ao_scheme_integer_typep(lt) && ao_scheme_integer_typep(rt)) {
-				int32_t l = ao_scheme_poly_integer(left);
-				int32_t r = ao_scheme_poly_integer(right);
+				int32_t l = ao_scheme_poly_integer(left, NULL);
+				int32_t r = ao_scheme_poly_integer(right, NULL);
 
 				switch (op) {
 				case builtin_less:
@@ -524,6 +547,7 @@ ao_scheme_compare(struct ao_scheme_cons *cons, enum ao_scheme_builtin_id op)
 				default:
 					break;
 				}
+#ifdef AO_SCHEME_FEATURE_FLOAT
 			} else if (ao_scheme_number_typep(lt) && ao_scheme_number_typep(rt)) {
 				float l, r;
 
@@ -553,9 +577,10 @@ ao_scheme_compare(struct ao_scheme_cons *cons, enum ao_scheme_builtin_id op)
 				default:
 					break;
 				}
+#endif /* AO_SCHEME_FEATURE_FLOAT */
 			} else if (lt == AO_SCHEME_STRING && rt == AO_SCHEME_STRING) {
-				int c = strcmp(ao_scheme_poly_string(left),
-					       ao_scheme_poly_string(right));
+				int c = strcmp(ao_scheme_poly_string(left)->val,
+					       ao_scheme_poly_string(right)->val);
 				switch (op) {
 				case builtin_less:
 					if (!(c < 0))
@@ -641,16 +666,16 @@ ao_scheme_do_string_to_list(struct ao_scheme_cons *cons)
 ao_poly
 ao_scheme_do_string_ref(struct ao_scheme_cons *cons)
 {
-	char *string;
+	char	*string;
 	int32_t ref;
 	if (!ao_scheme_check_argc(_ao_scheme_atom_string2dref, cons, 2, 2))
 		return AO_SCHEME_NIL;
 	if (!ao_scheme_check_argt(_ao_scheme_atom_string2dref, cons, 0, AO_SCHEME_STRING, 0))
 		return AO_SCHEME_NIL;
 	ref = ao_scheme_arg_int(_ao_scheme_atom_string2dref, cons, 1);
-	if (ref == AO_SCHEME_NOT_INTEGER)
+	if (ao_scheme_exception)
 		return AO_SCHEME_NIL;
-	string = ao_scheme_poly_string(ao_scheme_arg(cons, 0));
+	string = ao_scheme_poly_string(ao_scheme_arg(cons, 0))->val;
 	while (*string && ref) {
 		++string;
 		--ref;
@@ -666,20 +691,20 @@ ao_scheme_do_string_ref(struct ao_scheme_cons *cons)
 ao_poly
 ao_scheme_do_string_length(struct ao_scheme_cons *cons)
 {
-	char *string;
+	struct ao_scheme_string *string;
 
 	if (!ao_scheme_check_argc(_ao_scheme_atom_string2dlength, cons, 1, 1))
 		return AO_SCHEME_NIL;
 	if (!ao_scheme_check_argt(_ao_scheme_atom_string2dlength, cons, 0, AO_SCHEME_STRING, 0))
 		return AO_SCHEME_NIL;
 	string = ao_scheme_poly_string(ao_scheme_arg(cons, 0));
-	return ao_scheme_integer_poly(strlen(string));
+	return ao_scheme_integer_poly(strlen(string->val));
 }
 
 ao_poly
 ao_scheme_do_string_copy(struct ao_scheme_cons *cons)
 {
-	char *string;
+	struct ao_scheme_string	*string;
 
 	if (!ao_scheme_check_argc(_ao_scheme_atom_string2dcopy, cons, 1, 1))
 		return AO_SCHEME_NIL;
@@ -692,7 +717,7 @@ ao_scheme_do_string_copy(struct ao_scheme_cons *cons)
 ao_poly
 ao_scheme_do_string_set(struct ao_scheme_cons *cons)
 {
-	char *string;
+	char	*string;
 	int32_t ref;
 	int32_t val;
 
@@ -700,12 +725,12 @@ ao_scheme_do_string_set(struct ao_scheme_cons *cons)
 		return AO_SCHEME_NIL;
 	if (!ao_scheme_check_argt(_ao_scheme_atom_string2dset21, cons, 0, AO_SCHEME_STRING, 0))
 		return AO_SCHEME_NIL;
-	string = ao_scheme_poly_string(ao_scheme_arg(cons, 0));
+	string = ao_scheme_poly_string(ao_scheme_arg(cons, 0))->val;
 	ref = ao_scheme_arg_int(_ao_scheme_atom_string2dset21, cons, 1);
-	if (ref == AO_SCHEME_NOT_INTEGER)
+	if (ao_scheme_exception)
 		return AO_SCHEME_NIL;
 	val = ao_scheme_arg_int(_ao_scheme_atom_string2dset21, cons, 2);
-	if (val == AO_SCHEME_NOT_INTEGER)
+	if (ao_scheme_exception)
 		return AO_SCHEME_NIL;
 	while (*string && ref) {
 		++string;
@@ -736,7 +761,7 @@ ao_scheme_do_led(struct ao_scheme_cons *cons)
 	if (!ao_scheme_check_argc(_ao_scheme_atom_led, cons, 1, 1))
 		return AO_SCHEME_NIL;
 	led = ao_scheme_arg_int(_ao_scheme_atom_led, cons, 0);
-	if (led == AO_SCHEME_NOT_INTEGER)
+	if (ao_scheme_exception)
 		return AO_SCHEME_NIL;
 	led = ao_scheme_arg(cons, 0);
 	ao_scheme_os_led(ao_scheme_poly_int(led));
@@ -751,7 +776,7 @@ ao_scheme_do_delay(struct ao_scheme_cons *cons)
 	if (!ao_scheme_check_argc(_ao_scheme_atom_delay, cons, 1, 1))
 		return AO_SCHEME_NIL;
 	delay = ao_scheme_arg_int(_ao_scheme_atom_delay, cons, 0);
-	if (delay == AO_SCHEME_NOT_INTEGER)
+	if (ao_scheme_exception)
 		return AO_SCHEME_NIL;
 	ao_scheme_os_delay(delay);
 	return delay;
@@ -831,7 +856,7 @@ ao_scheme_do_pairp(struct ao_scheme_cons *cons)
 	if (!ao_scheme_check_argc(_ao_scheme_atom_led, cons, 1, 1))
 		return AO_SCHEME_NIL;
 	v = ao_scheme_arg(cons, 0);
-	if (v != AO_SCHEME_NIL && ao_scheme_poly_type(v) == AO_SCHEME_CONS)
+	if (ao_scheme_is_pair(v))
 		return _ao_scheme_bool_true;
 	return _ao_scheme_bool_false;
 }
@@ -839,6 +864,7 @@ ao_scheme_do_pairp(struct ao_scheme_cons *cons)
 ao_poly
 ao_scheme_do_integerp(struct ao_scheme_cons *cons)
 {
+#ifdef AO_SCHEME_FEATURE_BIGINT
 	if (!ao_scheme_check_argc(_ao_scheme_atom_led, cons, 1, 1))
 		return AO_SCHEME_NIL;
 	switch (ao_scheme_poly_type(ao_scheme_arg(cons, 0))) {
@@ -848,21 +874,32 @@ ao_scheme_do_integerp(struct ao_scheme_cons *cons)
 	default:
 		return _ao_scheme_bool_false;
 	}
+#else
+	return ao_scheme_do_typep(AO_SCHEME_INT, cons);
+#endif
 }
 
 ao_poly
 ao_scheme_do_numberp(struct ao_scheme_cons *cons)
 {
+#if defined(AO_SCHEME_FEATURE_BIGINT) || defined(AO_SCHEME_FEATURE_FLOAT)
 	if (!ao_scheme_check_argc(_ao_scheme_atom_led, cons, 1, 1))
 		return AO_SCHEME_NIL;
 	switch (ao_scheme_poly_type(ao_scheme_arg(cons, 0))) {
 	case AO_SCHEME_INT:
+#ifdef AO_SCHEME_FEATURE_BIGINT
 	case AO_SCHEME_BIGINT:
+#endif
+#ifdef AO_SCHEME_FEATURE_FLOAT
 	case AO_SCHEME_FLOAT:
+#endif
 		return _ao_scheme_bool_true;
 	default:
 		return _ao_scheme_bool_false;
 	}
+#else
+	return ao_scheme_do_integerp(cons);
+#endif
 }
 
 ao_poly
@@ -910,7 +947,7 @@ ao_scheme_do_listp(struct ao_scheme_cons *cons)
 	for (;;) {
 		if (v == AO_SCHEME_NIL)
 			return _ao_scheme_bool_true;
-		if (ao_scheme_poly_type(v) != AO_SCHEME_CONS)
+		if (!ao_scheme_is_cons(v))
 			return _ao_scheme_bool_false;
 		v = ao_scheme_poly_cons(v)->cdr;
 	}
@@ -943,7 +980,7 @@ ao_scheme_do_symbol_to_string(struct ao_scheme_cons *cons)
 		return AO_SCHEME_NIL;
 	if (!ao_scheme_check_argt(_ao_scheme_atom_led, cons, 0, AO_SCHEME_ATOM, 0))
 		return AO_SCHEME_NIL;
-	return ao_scheme_string_poly(ao_scheme_string_copy(ao_scheme_poly_atom(ao_scheme_arg(cons, 0))->name));
+	return ao_scheme_string_poly(ao_scheme_atom_to_string(ao_scheme_poly_atom(ao_scheme_arg(cons, 0))));
 }
 
 ao_poly
@@ -954,7 +991,7 @@ ao_scheme_do_string_to_symbol(struct ao_scheme_cons *cons)
 	if (!ao_scheme_check_argt(_ao_scheme_atom_led, cons, 0, AO_SCHEME_STRING, 0))
 		return AO_SCHEME_NIL;
 
-	return ao_scheme_atom_poly(ao_scheme_atom_intern(ao_scheme_poly_string(ao_scheme_arg(cons, 0))));
+	return ao_scheme_atom_poly(ao_scheme_string_to_atom(ao_scheme_poly_string(ao_scheme_arg(cons, 0))));;
 }
 
 ao_poly
@@ -974,7 +1011,7 @@ ao_scheme_do_write_char(struct ao_scheme_cons *cons)
 		return AO_SCHEME_NIL;
 	if (!ao_scheme_check_argt(_ao_scheme_atom_led, cons, 0, AO_SCHEME_INT, 0))
 		return AO_SCHEME_NIL;
-	putchar(ao_scheme_poly_integer(ao_scheme_arg(cons, 0)));
+	putchar(ao_scheme_poly_integer(ao_scheme_arg(cons, 0), NULL));
 	return _ao_scheme_bool_true;
 }
 
@@ -1017,6 +1054,8 @@ ao_scheme_do_jiffies_per_second(struct ao_scheme_cons *cons)
 	return (ao_scheme_int_poly(AO_SCHEME_JIFFIES_PER_SECOND));
 }
 
+#ifdef AO_SCHEME_FEATURE_VECTOR
+
 ao_poly
 ao_scheme_do_vector(struct ao_scheme_cons *cons)
 {
@@ -1031,7 +1070,7 @@ ao_scheme_do_make_vector(struct ao_scheme_cons *cons)
 	if (!ao_scheme_check_argc(_ao_scheme_atom_make2dvector, cons, 2, 2))
 		return AO_SCHEME_NIL;
 	k = ao_scheme_arg_int(_ao_scheme_atom_make2dvector, cons, 0);
-	if (k == AO_SCHEME_NOT_INTEGER)
+	if (ao_scheme_exception)
 		return AO_SCHEME_NIL;
 	return ao_scheme_vector_poly(ao_scheme_vector_alloc(k, ao_scheme_arg(cons, 1)));
 }
@@ -1092,5 +1131,7 @@ ao_scheme_do_vectorp(struct ao_scheme_cons *cons)
 	return ao_scheme_do_typep(AO_SCHEME_VECTOR, cons);
 }
 
+#endif /* AO_SCHEME_FEATURE_VECTOR */
+
 #define AO_SCHEME_BUILTIN_FUNCS
 #include "ao_scheme_builtin.h"
diff --git a/src/scheme/ao_scheme_builtin.txt b/src/scheme/ao_scheme_builtin.txt
index 17f5ea0c..23adf6ed 100644
--- a/src/scheme/ao_scheme_builtin.txt
+++ b/src/scheme/ao_scheme_builtin.txt
@@ -1,81 +1,84 @@
-f_lambda	eval
-f_lambda	read
-nlambda		lambda
-nlambda		nlambda
-nlambda		macro
-f_lambda	car
-f_lambda	cdr
-f_lambda	cons
-f_lambda	last
-f_lambda	length
-f_lambda	list_copy	list-copy
-nlambda		quote
-atom		quasiquote
-atom		unquote
-atom		unquote_splicing	unquote-splicing
-f_lambda	set
-macro		setq		set!
-f_lambda	def
-nlambda		cond
-nlambda		begin
-nlambda		while
-f_lambda	write
-f_lambda	display
-f_lambda	plus		+	string-append
-f_lambda	minus		-
-f_lambda	times		*
-f_lambda	divide		/
-f_lambda	modulo		modulo	%
-f_lambda	remainder
-f_lambda	quotient
-f_lambda	equal		=	eq?	eqv?
-f_lambda	less		<	string<?
-f_lambda	greater		>	string>?
-f_lambda	less_equal	<=	string<=?
-f_lambda	greater_equal	>=	string>=?
-f_lambda	flush_output		flush-output
-f_lambda	delay
-f_lambda	led
-f_lambda	save
-f_lambda	restore
-f_lambda	call_cc		call-with-current-continuation	call/cc
-f_lambda	collect
-f_lambda	nullp		null?
-f_lambda	not
-f_lambda	listp		list?
-f_lambda	pairp		pair?
-f_lambda	integerp	integer? exact? exact-integer?
-f_lambda	numberp		number? real?
-f_lambda	booleanp	boolean?
-f_lambda	set_car		set-car!
-f_lambda	set_cdr		set-cdr!
-f_lambda	symbolp		symbol?
-f_lambda	list_to_string		list->string
-f_lambda	string_to_list		string->list
-f_lambda	symbol_to_string	symbol->string
-f_lambda	string_to_symbol	string->symbol
-f_lambda	stringp		string?
-f_lambda	string_ref	string-ref
-f_lambda	string_set	string-set!
-f_lambda	string_copy	string-copy
-f_lambda	string_length	string-length
-f_lambda	procedurep	procedure?
-lambda		apply
-f_lambda	read_char	read-char
-f_lambda	write_char	write-char
-f_lambda	exit
-f_lambda	current_jiffy	current-jiffy
-f_lambda	current_second	current-second
-f_lambda	jiffies_per_second	jiffies-per-second
-f_lambda	finitep		finite?
-f_lambda	infinitep	infinite?
-f_lambda	inexactp	inexact?
-f_lambda	sqrt
-f_lambda	vector_ref	vector-ref
-f_lambda	vector_set	vector-set!
-f_lambda	vector
-f_lambda	make_vector	make-vector
-f_lambda	list_to_vector	list->vector
-f_lambda	vector_to_list	vector->list
-f_lambda	vector_length	vector-length
-f_lambda	vectorp		vector?
+BIGINT	feature		bigint
+all	atom		eof
+all	atom		else
+all	f_lambda	eval
+all	f_lambda	read
+all	nlambda		lambda
+all	nlambda		nlambda
+all	nlambda		macro
+all	f_lambda	car
+all	f_lambda	cdr
+all	f_lambda	cons
+all	f_lambda	last
+all	f_lambda	length
+all	f_lambda	list_copy	list-copy
+all	nlambda		quote
+QUASI	atom		quasiquote
+QUASI	atom		unquote
+QUASI	atom		unquote_splicing	unquote-splicing
+all	f_lambda	set
+all	macro		setq		set!
+all	f_lambda	def
+all	nlambda		cond
+all	nlambda		begin
+all	nlambda		while
+all	f_lambda	write
+all	f_lambda	display
+all	f_lambda	plus		+	string-append
+all	f_lambda	minus		-
+all	f_lambda	times		*
+all	f_lambda	divide		/
+all	f_lambda	modulo		modulo	%
+all	f_lambda	remainder
+all	f_lambda	quotient
+all	f_lambda	equal		=	eq?	eqv?
+all	f_lambda	less		<	string<?
+all	f_lambda	greater		>	string>?
+all	f_lambda	less_equal	<=	string<=?
+all	f_lambda	greater_equal	>=	string>=?
+all	f_lambda	flush_output		flush-output
+TIME	f_lambda	delay
+GPIO	f_lambda	led
+all	f_lambda	save
+all	f_lambda	restore
+all	f_lambda	call_cc		call-with-current-continuation	call/cc
+all	f_lambda	collect
+all	f_lambda	nullp		null?
+all	f_lambda	not
+all	f_lambda	listp		list?
+all	f_lambda	pairp		pair?
+all	f_lambda	integerp	integer? exact? exact-integer?
+all	f_lambda	numberp		number? real?
+all	f_lambda	booleanp	boolean?
+all	f_lambda	set_car		set-car!
+all	f_lambda	set_cdr		set-cdr!
+all	f_lambda	symbolp		symbol?
+all	f_lambda	list_to_string		list->string
+all	f_lambda	string_to_list		string->list
+all	f_lambda	symbol_to_string	symbol->string
+all	f_lambda	string_to_symbol	string->symbol
+all	f_lambda	stringp		string?
+all	f_lambda	string_ref	string-ref
+all	f_lambda	string_set	string-set!
+all	f_lambda	string_copy	string-copy
+all	f_lambda	string_length	string-length
+all	f_lambda	procedurep	procedure?
+all	lambda		apply
+all	f_lambda	read_char	read-char
+all	f_lambda	write_char	write-char
+all	f_lambda	exit
+TIME	f_lambda	current_jiffy	current-jiffy
+TIME	f_lambda	current_second	current-second
+TIME	f_lambda	jiffies_per_second	jiffies-per-second
+FLOAT	f_lambda	finitep		finite?
+FLOAT	f_lambda	infinitep	infinite?
+FLOAT	f_lambda	inexactp	inexact?
+FLOAT	f_lambda	sqrt
+VECTOR	f_lambda	vector_ref	vector-ref
+VECTOR	f_lambda	vector_set	vector-set!
+VECTOR	f_lambda	vector
+VECTOR	f_lambda	make_vector	make-vector
+VECTOR	f_lambda	list_to_vector	list->vector
+VECTOR	f_lambda	vector_to_list	vector->list
+VECTOR	f_lambda	vector_length	vector-length
+VECTOR	f_lambda	vectorp		vector?
diff --git a/src/scheme/ao_scheme_cons.c b/src/scheme/ao_scheme_cons.c
index 02512e15..a9ff5acd 100644
--- a/src/scheme/ao_scheme_cons.c
+++ b/src/scheme/ao_scheme_cons.c
@@ -24,8 +24,8 @@ static void cons_mark(void *addr)
 		ao_scheme_poly_mark(cons->car, 1);
 		if (!cdr)
 			break;
-		if (ao_scheme_poly_type(cdr) != AO_SCHEME_CONS) {
-			ao_scheme_poly_mark(cdr, 1);
+		if (!ao_scheme_is_cons(cdr)) {
+			ao_scheme_poly_mark(cdr, 0);
 			break;
 		}
 		cons = ao_scheme_poly_cons(cdr);
@@ -58,7 +58,7 @@ static void cons_move(void *addr)
 		cdr = cons->cdr;
 		if (!cdr)
 			break;
-		if (ao_scheme_poly_base_type(cdr) != AO_SCHEME_CONS) {
+		if (!ao_scheme_is_cons(cdr)) {
 			(void) ao_scheme_poly_move(&cons->cdr, 0);
 			break;
 		}
@@ -92,11 +92,11 @@ ao_scheme_cons_cons(ao_poly car, ao_poly cdr)
 		cons = ao_scheme_cons_free_list;
 		ao_scheme_cons_free_list = ao_scheme_poly_cons(cons->cdr);
 	} else {
-		ao_scheme_poly_stash(0, car);
-		ao_scheme_poly_stash(1, cdr);
+		ao_scheme_poly_stash(car);
+		ao_scheme_poly_stash(cdr);
 		cons = ao_scheme_alloc(sizeof (struct ao_scheme_cons));
-		cdr = ao_scheme_poly_fetch(1);
-		car = ao_scheme_poly_fetch(0);
+		cdr = ao_scheme_poly_fetch();
+		car = ao_scheme_poly_fetch();
 		if (!cons)
 			return NULL;
 	}
@@ -111,7 +111,7 @@ ao_scheme_cons_cdr(struct ao_scheme_cons *cons)
 	ao_poly	cdr = cons->cdr;
 	if (cdr == AO_SCHEME_NIL)
 		return NULL;
-	if (ao_scheme_poly_type(cdr) != AO_SCHEME_CONS) {
+	if (!ao_scheme_is_cons(cdr)) {
 		(void) ao_scheme_error(AO_SCHEME_INVALID, "improper cdr %v", cdr);
 		return NULL;
 	}
@@ -119,7 +119,7 @@ ao_scheme_cons_cdr(struct ao_scheme_cons *cons)
 }
 
 ao_poly
-ao_scheme__cons(ao_poly car, ao_poly cdr)
+ao_scheme_cons(ao_poly car, ao_poly cdr)
 {
 	return ao_scheme_cons_poly(ao_scheme_cons_cons(car, cdr));
 }
@@ -134,13 +134,13 @@ ao_scheme_cons_copy(struct ao_scheme_cons *cons)
 		struct ao_scheme_cons	*new;
 		ao_poly cdr;
 
-		ao_scheme_cons_stash(0, cons);
-		ao_scheme_cons_stash(1, head);
-		ao_scheme_poly_stash(0, ao_scheme_cons_poly(tail));
+		ao_scheme_cons_stash(cons);
+		ao_scheme_cons_stash(head);
+		ao_scheme_cons_stash(tail);
 		new = ao_scheme_alloc(sizeof (struct ao_scheme_cons));
-		cons = ao_scheme_cons_fetch(0);
-		head = ao_scheme_cons_fetch(1);
-		tail = ao_scheme_poly_cons(ao_scheme_poly_fetch(0));
+		tail = ao_scheme_cons_fetch();
+		head = ao_scheme_cons_fetch();
+		cons = ao_scheme_cons_fetch();
 		if (!new)
 			return AO_SCHEME_NIL;
 		new->car = cons->car;
@@ -151,7 +151,7 @@ ao_scheme_cons_copy(struct ao_scheme_cons *cons)
 			tail->cdr = ao_scheme_cons_poly(new);
 		tail = new;
 		cdr = cons->cdr;
-		if (ao_scheme_poly_type(cdr) != AO_SCHEME_CONS) {
+		if (!ao_scheme_is_cons(cdr)) {
 			tail->cdr = cdr;
 			break;
 		}
@@ -175,52 +175,51 @@ ao_scheme_cons_free(struct ao_scheme_cons *cons)
 }
 
 void
-ao_scheme_cons_write(ao_poly c)
+ao_scheme_cons_write(ao_poly c, bool write)
 {
 	struct ao_scheme_cons	*cons = ao_scheme_poly_cons(c);
+	struct ao_scheme_cons	*clear = cons;
 	ao_poly			cdr;
-	int			first = 1;
+	int			written = 0;
 
+	ao_scheme_print_start();
 	printf("(");
 	while (cons) {
-		if (!first)
+		if (written != 0)
 			printf(" ");
-		ao_scheme_poly_write(cons->car);
-		cdr = cons->cdr;
-		if (cdr == c) {
-			printf(" ...");
+
+		/* Note if there's recursion in printing. Not
+		 * as good as actual references, but at least
+		 * we don't infinite loop...
+		 */
+		if (ao_scheme_print_mark_addr(cons)) {
+			printf("...");
 			break;
 		}
-		if (ao_scheme_poly_type(cdr) == AO_SCHEME_CONS) {
-			cons = ao_scheme_poly_cons(cdr);
-			first = 0;
-		} else {
+
+		ao_scheme_poly_write(cons->car, write);
+
+		/* keep track of how many pairs have been printed */
+		written++;
+
+		cdr = cons->cdr;
+		if (!ao_scheme_is_cons(cdr)) {
 			printf(" . ");
-			ao_scheme_poly_write(cdr);
-			cons = NULL;
+			ao_scheme_poly_write(cdr, write);
+			break;
 		}
+		cons = ao_scheme_poly_cons(cdr);
 	}
 	printf(")");
-}
 
-void
-ao_scheme_cons_display(ao_poly c)
-{
-	struct ao_scheme_cons	*cons = ao_scheme_poly_cons(c);
-	ao_poly			cdr;
+	if (ao_scheme_print_stop()) {
 
-	while (cons) {
-		ao_scheme_poly_display(cons->car);
-		cdr = cons->cdr;
-		if (cdr == c) {
-			printf("...");
-			break;
-		}
-		if (ao_scheme_poly_type(cdr) == AO_SCHEME_CONS)
-			cons = ao_scheme_poly_cons(cdr);
-		else {
-			ao_scheme_poly_display(cdr);
-			cons = NULL;
+		/* If we're still printing, clear the print marks on
+		 * all printed pairs
+		 */
+		while (written--) {
+			ao_scheme_print_clear_addr(clear);
+			clear = ao_scheme_poly_cons(clear->cdr);
 		}
 	}
 }
diff --git a/src/scheme/ao_scheme_const.scheme b/src/scheme/ao_scheme_const.scheme
index ab6a309a..4616477f 100644
--- a/src/scheme/ao_scheme_const.scheme
+++ b/src/scheme/ao_scheme_const.scheme
@@ -248,7 +248,7 @@
    (macro (first . rest)
 					; check for alternate lambda definition form
 
-	  (cond ((list? first)
+	  (cond ((pair? first)
 		 (set! rest
 		       (append
 			(list
@@ -640,7 +640,7 @@
 (char-whitespace? #\0)
 (char-whitespace? #\space)
 
-(define (char->integer c) c)
+(define char->integer (macro (v) v))
 (define integer->char char->integer)
 
 (define (char-upcase c) (if (char-lower-case? c) (+ c (- #\A #\a)) c))
@@ -805,9 +805,3 @@
   )
 
 (case 12 (1 "one") (2 "two") (3 => (lambda (x) (write "the value is" x))) (12 "twelve") (else "else"))
-
-;(define number->string (lambda (arg . opt)
-;			      (let ((base (if (null? opt) 10 (car opt)))
-					;
-;
-				
diff --git a/src/scheme/ao_scheme_error.c b/src/scheme/ao_scheme_error.c
index d580a2c0..6a71ca51 100644
--- a/src/scheme/ao_scheme_error.c
+++ b/src/scheme/ao_scheme_error.c
@@ -16,74 +16,7 @@
 #include <stdarg.h>
 
 void
-ao_scheme_error_poly(char *name, ao_poly poly, ao_poly last)
-{
-	int first = 1;
-	printf("\t\t%s(", name);
-	if (ao_scheme_poly_type(poly) == AO_SCHEME_CONS) {
-		if (poly) {
-			while (poly) {
-				struct ao_scheme_cons *cons = ao_scheme_poly_cons(poly);
-				if (!first)
-					printf("\t\t         ");
-				else
-					first = 0;
-				ao_scheme_poly_write(cons->car);
-				printf("\n");
-				if (poly == last)
-					break;
-				poly = cons->cdr;
-			}
-			printf("\t\t         )\n");
-		} else
-			printf(")\n");
-	} else {
-		ao_scheme_poly_write(poly);
-		printf("\n");
-	}
-}
-
-static void tabs(int indent)
-{
-	while (indent--)
-		printf("\t");
-}
-
-void
-ao_scheme_error_frame(int indent, char *name, struct ao_scheme_frame *frame)
-{
-	int			f;
-
-	tabs(indent);
-	printf ("%s{", name);
-	if (frame) {
-		struct ao_scheme_frame_vals	*vals = ao_scheme_poly_frame_vals(frame->vals);
-		if (frame->type & AO_SCHEME_FRAME_PRINT)
-			printf("recurse...");
-		else {
-			frame->type |= AO_SCHEME_FRAME_PRINT;
-			for (f = 0; f < frame->num; f++) {
-				if (f != 0) {
-					tabs(indent);
-					printf("         ");
-				}
-				ao_scheme_poly_write(vals->vals[f].atom);
-				printf(" = ");
-				ao_scheme_poly_write(vals->vals[f].val);
-				printf("\n");
-			}
-			if (frame->prev)
-				ao_scheme_error_frame(indent + 1, "prev:   ", ao_scheme_poly_frame(frame->prev));
-			frame->type &= ~AO_SCHEME_FRAME_PRINT;
-		}
-		tabs(indent);
-		printf("        }\n");
-	} else
-		printf ("}\n");
-}
-
-void
-ao_scheme_vprintf(char *format, va_list args)
+ao_scheme_vprintf(const char *format, va_list args)
 {
 	char c;
 
@@ -91,7 +24,10 @@ ao_scheme_vprintf(char *format, va_list args)
 		if (c == '%') {
 			switch (c = *format++) {
 			case 'v':
-				ao_scheme_poly_write((ao_poly) va_arg(args, unsigned int));
+				ao_scheme_poly_write((ao_poly) va_arg(args, unsigned int), true);
+				break;
+			case 'V':
+				ao_scheme_poly_write((ao_poly) va_arg(args, unsigned int), false);
 				break;
 			case 'p':
 				printf("%p", va_arg(args, void *));
@@ -112,7 +48,7 @@ ao_scheme_vprintf(char *format, va_list args)
 }
 
 void
-ao_scheme_printf(char *format, ...)
+ao_scheme_printf(const char *format, ...)
 {
 	va_list args;
 	va_start(args, format);
@@ -121,7 +57,7 @@ ao_scheme_printf(char *format, ...)
 }
 
 ao_poly
-ao_scheme_error(int error, char *format, ...)
+ao_scheme_error(int error, const char *format, ...)
 {
 	va_list	args;
 
@@ -133,7 +69,7 @@ ao_scheme_error(int error, char *format, ...)
 	ao_scheme_printf("Value:  %v\n", ao_scheme_v);
 	ao_scheme_printf("Frame:  %v\n", ao_scheme_frame_poly(ao_scheme_frame_current));
 	printf("Stack:\n");
-	ao_scheme_stack_write(ao_scheme_stack_poly(ao_scheme_stack));
+	ao_scheme_stack_write(ao_scheme_stack_poly(ao_scheme_stack), true);
 	ao_scheme_printf("Globals: %v\n", ao_scheme_frame_poly(ao_scheme_frame_global));
 	return AO_SCHEME_NIL;
 }
diff --git a/src/scheme/ao_scheme_eval.c b/src/scheme/ao_scheme_eval.c
index 907ecf0b..91f6a84f 100644
--- a/src/scheme/ao_scheme_eval.c
+++ b/src/scheme/ao_scheme_eval.c
@@ -17,7 +17,6 @@
 
 struct ao_scheme_stack		*ao_scheme_stack;
 ao_poly				ao_scheme_v;
-uint8_t				ao_scheme_skip_cons_free;
 
 ao_poly
 ao_scheme_set_cond(struct ao_scheme_cons *c)
@@ -207,7 +206,7 @@ ao_scheme_eval_formal(void)
 	}
 
 	/* Append formal to list of values */
-	formal = ao_scheme__cons(ao_scheme_v, AO_SCHEME_NIL);
+	formal = ao_scheme_cons(ao_scheme_v, AO_SCHEME_NIL);
 	if (!formal)
 		return 0;
 
@@ -265,7 +264,7 @@ ao_scheme_eval_exec(void)
 				DBGI("set "); DBG_POLY(atom); DBG(" = "); DBG_POLY(val); DBG("\n");
 			});
 		builtin = ao_scheme_poly_builtin(ao_scheme_v);
-		if (builtin && (builtin->args & AO_SCHEME_FUNC_FREE_ARGS) && !ao_scheme_stack_marked(ao_scheme_stack) && !ao_scheme_skip_cons_free) {
+		if (builtin && (builtin->args & AO_SCHEME_FUNC_FREE_ARGS) && !ao_scheme_stack_marked(ao_scheme_stack)) {
 			struct ao_scheme_cons *cons = ao_scheme_poly_cons(ao_scheme_stack->values);
 			ao_scheme_stack->values = AO_SCHEME_NIL;
 			ao_scheme_cons_free(cons);
@@ -294,7 +293,6 @@ ao_scheme_eval_exec(void)
 		DBGI(".. frame "); DBG_POLY(ao_scheme_frame_poly(ao_scheme_frame_current)); DBG("\n");
 		break;
 	}
-	ao_scheme_skip_cons_free = 0;
 	return 1;
 }
 
@@ -325,7 +323,7 @@ ao_scheme_eval_apply(void)
 	ao_scheme_v = ao_scheme_poly_cons(ao_scheme_stack->values)->car;
 	DBGI("apply: "); DBG_POLY(ao_scheme_stack->values); DBG ("\n");
 	ao_scheme_stack->state = eval_exec;
-	ao_scheme_skip_cons_free = 1;
+	ao_scheme_stack_mark(ao_scheme_stack);
 	return 1;
 }
 
@@ -350,7 +348,7 @@ ao_scheme_eval_cond(void)
 		ao_scheme_stack->state = eval_val;
 	} else {
 		ao_scheme_v = ao_scheme_poly_cons(ao_scheme_stack->sexprs)->car;
-		if (!ao_scheme_v || ao_scheme_poly_type(ao_scheme_v) != AO_SCHEME_CONS) {
+		if (!ao_scheme_is_pair(ao_scheme_v)) {
 			ao_scheme_error(AO_SCHEME_INVALID, "invalid cond clause");
 			return 0;
 		}
@@ -494,7 +492,7 @@ ao_scheme_eval_macro(void)
 
 	if (ao_scheme_v == AO_SCHEME_NIL)
 		ao_scheme_abort();
-	if (ao_scheme_poly_type(ao_scheme_v) == AO_SCHEME_CONS) {
+	if (ao_scheme_is_cons(ao_scheme_v)) {
 		*ao_scheme_poly_cons(ao_scheme_stack->sexprs) = *ao_scheme_poly_cons(ao_scheme_v);
 		ao_scheme_v = ao_scheme_stack->sexprs;
 		DBGI("sexprs rewritten to: "); DBG_POLY(ao_scheme_v); DBG("\n");
diff --git a/src/scheme/ao_scheme_float.c b/src/scheme/ao_scheme_float.c
index 99249030..d8501548 100644
--- a/src/scheme/ao_scheme_float.c
+++ b/src/scheme/ao_scheme_float.c
@@ -15,6 +15,8 @@
 #include "ao_scheme.h"
 #include <math.h>
 
+#ifdef AO_SCHEME_FEATURE_FLOAT
+
 static void float_mark(void *addr)
 {
 	(void) addr;
@@ -44,11 +46,12 @@ const struct ao_scheme_type ao_scheme_float_type = {
 #endif
 
 void
-ao_scheme_float_write(ao_poly p)
+ao_scheme_float_write(ao_poly p, bool write)
 {
 	struct ao_scheme_float *f = ao_scheme_poly_float(p);
 	float	v = f->value;
 
+	(void) write;
 	if (isnanf(v))
 		printf("+nan.0");
 	else if (isinff(v)) {
@@ -67,10 +70,10 @@ ao_scheme_poly_number(ao_poly p)
 	switch (ao_scheme_poly_base_type(p)) {
 	case AO_SCHEME_INT:
 		return ao_scheme_poly_int(p);
+	case AO_SCHEME_BIGINT:
+		return ao_scheme_poly_bigint(p)->value;
 	case AO_SCHEME_OTHER:
 		switch (ao_scheme_other_type(ao_scheme_poly_other(p))) {
-		case AO_SCHEME_BIGINT:
-			return ao_scheme_bigint_int(ao_scheme_poly_bigint(p)->value);
 		case AO_SCHEME_FLOAT:
 			return ao_scheme_poly_float(p)->value;
 		}
@@ -150,3 +153,4 @@ ao_scheme_do_sqrt(struct ao_scheme_cons *cons)
 		return ao_scheme_error(AO_SCHEME_INVALID, "%s: non-numeric", ao_scheme_poly_atom(_ao_scheme_atom_sqrt)->name);
 	return ao_scheme_float_get(sqrtf(ao_scheme_poly_number(value)));
 }
+#endif
diff --git a/src/scheme/ao_scheme_frame.c b/src/scheme/ao_scheme_frame.c
index e5d481e7..16da62fb 100644
--- a/src/scheme/ao_scheme_frame.c
+++ b/src/scheme/ao_scheme_frame.c
@@ -41,7 +41,6 @@ frame_vals_mark(void *addr)
 			  ao_scheme_poly_atom(v->atom)->name,
 			  MDBG_OFFSET(ao_scheme_ref(v->atom)),
 			  MDBG_OFFSET(ao_scheme_ref(v->val)), f);
-		MDBG_DO(ao_scheme_poly_write(v->val));
 		MDBG_DO(printf("\n"));
 	}
 }
@@ -84,10 +83,11 @@ frame_mark(void *addr)
 	struct ao_scheme_frame	*frame = addr;
 
 	for (;;) {
+		struct ao_scheme_frame_vals	*vals = ao_scheme_poly_frame_vals(frame->vals);
+
 		MDBG_MOVE("frame mark %d\n", MDBG_OFFSET(frame));
-		if (!AO_SCHEME_IS_POOL(frame))
-			break;
-		ao_scheme_poly_mark(frame->vals, 0);
+		if (!ao_scheme_mark_memory(&ao_scheme_frame_vals_type, vals))
+			frame_vals_mark(vals);
 		frame = ao_scheme_poly_frame(frame->prev);
 		MDBG_MOVE("frame next %d\n", MDBG_OFFSET(frame));
 		if (!frame)
@@ -103,13 +103,17 @@ frame_move(void *addr)
 	struct ao_scheme_frame	*frame = addr;
 
 	for (;;) {
-		struct ao_scheme_frame	*prev;
-		int			ret;
+		struct ao_scheme_frame		*prev;
+		struct ao_scheme_frame_vals	*vals;
+		int				ret;
 
 		MDBG_MOVE("frame move %d\n", MDBG_OFFSET(frame));
-		if (!AO_SCHEME_IS_POOL(frame))
-			break;
-		ao_scheme_poly_move(&frame->vals, 0);
+		vals = ao_scheme_poly_frame_vals(frame->vals);
+		if (!ao_scheme_move_memory(&ao_scheme_frame_vals_type, (void **) &vals))
+			frame_vals_move(vals);
+		if (vals != ao_scheme_poly_frame_vals(frame->vals))
+			frame->vals = ao_scheme_frame_vals_poly(vals);
+
 		prev = ao_scheme_poly_frame(frame->prev);
 		if (!prev)
 			break;
@@ -133,32 +137,53 @@ const struct ao_scheme_type ao_scheme_frame_type = {
 	.name = "frame",
 };
 
+int ao_scheme_frame_print_indent;
+
+static void
+ao_scheme_frame_indent(int extra)
+{
+	int				i;
+	putchar('\n');
+	for (i = 0; i < ao_scheme_frame_print_indent+extra; i++)
+		putchar('\t');
+}
+
 void
-ao_scheme_frame_write(ao_poly p)
+ao_scheme_frame_write(ao_poly p, bool write)
 {
 	struct ao_scheme_frame		*frame = ao_scheme_poly_frame(p);
+	struct ao_scheme_frame		*clear = frame;
 	struct ao_scheme_frame_vals	*vals = ao_scheme_poly_frame_vals(frame->vals);
 	int				f;
+	int				written = 0;
 
-	printf ("{");
-	if (frame) {
-		if (frame->type & AO_SCHEME_FRAME_PRINT)
+	ao_scheme_print_start();
+	while (frame) {
+		if (written != 0)
+			printf(", ");
+		if (ao_scheme_print_mark_addr(frame)) {
 			printf("recurse...");
-		else {
-			frame->type |= AO_SCHEME_FRAME_PRINT;
-			for (f = 0; f < frame->num; f++) {
-				if (f != 0)
-					printf(", ");
-				ao_scheme_poly_write(vals->vals[f].atom);
-				printf(" = ");
-				ao_scheme_poly_write(vals->vals[f].val);
-			}
-			if (frame->prev)
-				ao_scheme_poly_write(frame->prev);
-			frame->type &= ~AO_SCHEME_FRAME_PRINT;
+			break;
+		}
+
+		putchar('{');
+		written++;
+		for (f = 0; f < frame->num; f++) {
+			ao_scheme_frame_indent(1);
+			ao_scheme_poly_write(vals->vals[f].atom, write);
+			printf(" = ");
+			ao_scheme_poly_write(vals->vals[f].val, write);
+		}
+		frame = ao_scheme_poly_frame(frame->prev);
+		ao_scheme_frame_indent(0);
+		putchar('}');
+	}
+	if (ao_scheme_print_stop()) {
+		while (written--) {
+			ao_scheme_print_clear_addr(clear);
+			clear = ao_scheme_poly_frame(clear->prev);
 		}
 	}
-	printf("}");
 }
 
 static int
@@ -225,9 +250,9 @@ ao_scheme_frame_new(int num)
 		frame->num = 0;
 		frame->prev = AO_SCHEME_NIL;
 		frame->vals = AO_SCHEME_NIL;
-		ao_scheme_frame_stash(0, frame);
+		ao_scheme_frame_stash(frame);
 		vals = ao_scheme_frame_vals_new(num);
-		frame = ao_scheme_frame_fetch(0);
+		frame = ao_scheme_frame_fetch();
 		if (!vals)
 			return NULL;
 		frame->vals = ao_scheme_frame_vals_poly(vals);
@@ -271,9 +296,9 @@ ao_scheme_frame_realloc(struct ao_scheme_frame *frame, int new_num)
 
 	if (new_num == frame->num)
 		return frame;
-	ao_scheme_frame_stash(0, frame);
+	ao_scheme_frame_stash(frame);
 	new_vals = ao_scheme_frame_vals_new(new_num);
-	frame = ao_scheme_frame_fetch(0);
+	frame = ao_scheme_frame_fetch();
 	if (!new_vals)
 		return NULL;
 	vals = ao_scheme_poly_frame_vals(frame->vals);
@@ -306,11 +331,11 @@ ao_scheme_frame_add(struct ao_scheme_frame *frame, ao_poly atom, ao_poly val)
 
 	if (!ref) {
 		int f = frame->num;
-		ao_scheme_poly_stash(0, atom);
-		ao_scheme_poly_stash(1, val);
+		ao_scheme_poly_stash(atom);
+		ao_scheme_poly_stash(val);
 		frame = ao_scheme_frame_realloc(frame, f + 1);
-		val = ao_scheme_poly_fetch(1);
-		atom = ao_scheme_poly_fetch(0);
+		val = ao_scheme_poly_fetch();
+		atom = ao_scheme_poly_fetch();
 		if (!frame)
 			return AO_SCHEME_NIL;
 		ao_scheme_frame_bind(frame, frame->num - 1, atom, val);
diff --git a/src/scheme/ao_scheme_int.c b/src/scheme/ao_scheme_int.c
index 350a5d35..01b571c0 100644
--- a/src/scheme/ao_scheme_int.c
+++ b/src/scheme/ao_scheme_int.c
@@ -15,23 +15,29 @@
 #include "ao_scheme.h"
 
 void
-ao_scheme_int_write(ao_poly p)
+ao_scheme_int_write(ao_poly p, bool write)
 {
 	int i = ao_scheme_poly_int(p);
+	(void) write;
 	printf("%d", i);
 }
 
+#ifdef AO_SCHEME_FEATURE_BIGINT
+
 int32_t
-ao_scheme_poly_integer(ao_poly p)
+ao_scheme_poly_integer(ao_poly p, bool *fail)
 {
+	if (fail)
+		*fail = false;
 	switch (ao_scheme_poly_base_type(p)) {
 	case AO_SCHEME_INT:
 		return ao_scheme_poly_int(p);
-	case AO_SCHEME_OTHER:
-		if (ao_scheme_other_type(ao_scheme_poly_other(p)) == AO_SCHEME_BIGINT)
-			return ao_scheme_bigint_int(ao_scheme_poly_bigint(p)->value);
+	case AO_SCHEME_BIGINT:
+		return ao_scheme_poly_bigint(p)->value;
 	}
-	return AO_SCHEME_NOT_INTEGER;
+	if (fail)
+		*fail = true;
+	return 0;
 }
 
 ao_poly
@@ -42,7 +48,7 @@ ao_scheme_integer_poly(int32_t p)
 	if (AO_SCHEME_MIN_INT <= p && p <= AO_SCHEME_MAX_INT)
 		return ao_scheme_int_poly(p);
 	bi = ao_scheme_alloc(sizeof (struct ao_scheme_bigint));
-	bi->value = ao_scheme_int_bigint(p);
+	bi->value = p;
 	return ao_scheme_bigint_poly(bi);
 }
 
@@ -71,9 +77,11 @@ const struct ao_scheme_type ao_scheme_bigint_type = {
 };
 
 void
-ao_scheme_bigint_write(ao_poly p)
+ao_scheme_bigint_write(ao_poly p, bool write)
 {
 	struct ao_scheme_bigint	*bi = ao_scheme_poly_bigint(p);
 
-	printf("%d", ao_scheme_bigint_int(bi->value));
+	(void) write;
+	printf("%d", bi->value);
 }
+#endif /* AO_SCHEME_FEATURE_BIGINT */
diff --git a/src/scheme/ao_scheme_lambda.c b/src/scheme/ao_scheme_lambda.c
index ec6f858c..e818d7b0 100644
--- a/src/scheme/ao_scheme_lambda.c
+++ b/src/scheme/ao_scheme_lambda.c
@@ -17,14 +17,14 @@
 
 #include "ao_scheme.h"
 
-int
+static int
 lambda_size(void *addr)
 {
 	(void) addr;
 	return sizeof (struct ao_scheme_lambda);
 }
 
-void
+static void
 lambda_mark(void *addr)
 {
 	struct ao_scheme_lambda	*lambda = addr;
@@ -33,7 +33,7 @@ lambda_mark(void *addr)
 	ao_scheme_poly_mark(lambda->frame, 0);
 }
 
-void
+static void
 lambda_move(void *addr)
 {
 	struct ao_scheme_lambda	*lambda = addr;
@@ -50,7 +50,7 @@ const struct ao_scheme_type ao_scheme_lambda_type = {
 };
 
 void
-ao_scheme_lambda_write(ao_poly poly)
+ao_scheme_lambda_write(ao_poly poly, bool write)
 {
 	struct ao_scheme_lambda	*lambda = ao_scheme_poly_lambda(poly);
 	struct ao_scheme_cons	*cons = ao_scheme_poly_cons(lambda->code);
@@ -59,13 +59,13 @@ ao_scheme_lambda_write(ao_poly poly)
 	printf("%s", ao_scheme_args_name(lambda->args));
 	while (cons) {
 		printf(" ");
-		ao_scheme_poly_write(cons->car);
+		ao_scheme_poly_write(cons->car, write);
 		cons = ao_scheme_poly_cons(cons->cdr);
 	}
 	printf(")");
 }
 
-ao_poly
+static ao_poly
 ao_scheme_lambda_alloc(struct ao_scheme_cons *code, int args)
 {
 	struct ao_scheme_lambda	*lambda;
@@ -89,9 +89,9 @@ ao_scheme_lambda_alloc(struct ao_scheme_cons *code, int args)
 		}
 	}
 
-	ao_scheme_cons_stash(0, code);
+	ao_scheme_cons_stash(code);
 	lambda = ao_scheme_alloc(sizeof (struct ao_scheme_lambda));
-	code = ao_scheme_cons_fetch(0);
+	code = ao_scheme_cons_fetch();
 	if (!lambda)
 		return AO_SCHEME_NIL;
 
@@ -160,9 +160,9 @@ ao_scheme_lambda_eval(void)
 			return ao_scheme_error(AO_SCHEME_INVALID, "need at least %d args, got %d", args_wanted, args_provided);
 	}
 
-	ao_scheme_poly_stash(1, varargs);
+	ao_scheme_poly_stash(varargs);
 	next_frame = ao_scheme_frame_new(args_wanted + (varargs != AO_SCHEME_NIL));
-	varargs = ao_scheme_poly_fetch(1);
+	varargs = ao_scheme_poly_fetch();
 	if (!next_frame)
 		return AO_SCHEME_NIL;
 
diff --git a/src/scheme/ao_scheme_make_builtin b/src/scheme/ao_scheme_make_builtin
index 8e9c2c0b..a4d8326f 100644
--- a/src/scheme/ao_scheme_make_builtin
+++ b/src/scheme/ao_scheme_make_builtin
@@ -1,6 +1,7 @@
 #!/usr/bin/nickle
 
 typedef struct {
+	string	feature;
 	string	type;
 	string	c_name;
 	string[*]	lisp_names;
@@ -12,6 +13,7 @@ string[string] type_map = {
 	"macro" => "MACRO",
 	"f_lambda" => "F_LAMBDA",
 	"atom" => "atom",
+	"feature" => "feature",
 };
 
 string[*]
@@ -19,9 +21,9 @@ make_lisp(string[*] tokens)
 {
 	string[...] lisp = {};
 
-	if (dim(tokens) < 3)
+	if (dim(tokens) < 4)
 		return (string[1]) { tokens[dim(tokens) - 1] };
-	return (string[dim(tokens)-2]) { [i] = tokens[i+2] };
+	return (string[dim(tokens)-3]) { [i] = tokens[i+3] };
 }
 
 builtin_t
@@ -30,8 +32,9 @@ read_builtin(file f) {
 	string[*]	tokens = String::wordsplit(line, " \t");
 
 	return (builtin_t) {
-		.type = dim(tokens) > 0 ? type_map[tokens[0]] : "#",
-		.c_name = dim(tokens) > 1 ? tokens[1] : "#",
+		.feature = dim(tokens) > 0 ? tokens[0] : "#",
+		.type = dim(tokens) > 1 ? type_map[tokens[1]] : "#",
+		.c_name = dim(tokens) > 2 ? tokens[2] : "#",
 		.lisp_names = make_lisp(tokens),
 	};
 }
@@ -49,16 +52,37 @@ read_builtins(file f) {
 	return builtins;
 }
 
+void
+dump_ifdef(builtin_t builtin)
+{
+	if (builtin.feature != "all")
+		printf("#ifdef AO_SCHEME_FEATURE_%s\n", builtin.feature);
+}
+
+void
+dump_endif(builtin_t builtin)
+{
+	if (builtin.feature != "all")
+		printf("#endif /* AO_SCHEME_FEATURE_%s */\n", builtin.feature);
+}
+
 bool is_atom(builtin_t b) = b.type == "atom";
 
+bool is_func(builtin_t b) = b.type != "atom" && b.type != "feature";
+
+bool is_feature(builtin_t b) = b.type == "feature";
+
 void
 dump_ids(builtin_t[*] builtins) {
 	printf("#ifdef AO_SCHEME_BUILTIN_ID\n");
 	printf("#undef AO_SCHEME_BUILTIN_ID\n");
 	printf("enum ao_scheme_builtin_id {\n");
 	for (int i = 0; i < dim(builtins); i++)
-		if (!is_atom(builtins[i]))
+		if (is_func(builtins[i])) {
+			dump_ifdef(builtins[i]);
 			printf("\tbuiltin_%s,\n", builtins[i].c_name);
+			dump_endif(builtins[i]);
+		}
 	printf("\t_builtin_last\n");
 	printf("};\n");
 	printf("#endif /* AO_SCHEME_BUILTIN_ID */\n");
@@ -71,10 +95,13 @@ dump_casename(builtin_t[*] builtins) {
 	printf("static char *ao_scheme_builtin_name(enum ao_scheme_builtin_id b) {\n");
 	printf("\tswitch(b) {\n");
 	for (int i = 0; i < dim(builtins); i++)
-		if (!is_atom(builtins[i]))
+		if (is_func(builtins[i])) {
+			dump_ifdef(builtins[i]);
 			printf("\tcase builtin_%s: return ao_scheme_poly_atom(_atom(\"%s\"))->name;\n",
 			       builtins[i].c_name, builtins[i].lisp_names[0]);
-	printf("\tdefault: return \"???\";\n");
+			dump_endif(builtins[i]);
+		}
+	printf("\tdefault: return (char *) \"???\";\n");
 	printf("\t}\n");
 	printf("}\n");
 	printf("#endif /* AO_SCHEME_BUILTIN_CASENAME */\n");
@@ -97,11 +124,13 @@ dump_arrayname(builtin_t[*] builtins) {
 	printf("#undef AO_SCHEME_BUILTIN_ARRAYNAME\n");
 	printf("static const ao_poly builtin_names[] = {\n");
 	for (int i = 0; i < dim(builtins); i++) {
-		if (!is_atom(builtins[i])) {
+		if (is_func(builtins[i])) {
+			dump_ifdef(builtins[i]);
 			printf("\t[builtin_%s] = _ao_scheme_atom_",
 			       builtins[i].c_name);
 			cify_lisp(builtins[i].lisp_names[0]);
 			printf(",\n");
+			dump_endif(builtins[i]);
 		}
 	}
 	printf("};\n");
@@ -114,10 +143,13 @@ dump_funcs(builtin_t[*] builtins) {
 	printf("#undef AO_SCHEME_BUILTIN_FUNCS\n");
 	printf("const ao_scheme_func_t ao_scheme_builtins[] = {\n");
 	for (int i = 0; i < dim(builtins); i++) {
-		if (!is_atom(builtins[i]))
+		if (is_func(builtins[i])) {
+			dump_ifdef(builtins[i]);
 			printf("\t[builtin_%s] = ao_scheme_do_%s,\n",
 			       builtins[i].c_name,
 			       builtins[i].c_name);
+			dump_endif(builtins[i]);
+		}
 	}
 	printf("};\n");
 	printf("#endif /* AO_SCHEME_BUILTIN_FUNCS */\n");
@@ -128,10 +160,12 @@ dump_decls(builtin_t[*] builtins) {
 	printf("#ifdef AO_SCHEME_BUILTIN_DECLS\n");
 	printf("#undef AO_SCHEME_BUILTIN_DECLS\n");
 	for (int i = 0; i < dim(builtins); i++) {
-		if (!is_atom(builtins[i])) {
+		if (is_func(builtins[i])) {
+			dump_ifdef(builtins[i]);
 			printf("ao_poly\n");
 			printf("ao_scheme_do_%s(struct ao_scheme_cons *cons);\n",
 			       builtins[i].c_name);
+			dump_endif(builtins[i]);
 		}
 	}
 	printf("#endif /* AO_SCHEME_BUILTIN_DECLS */\n");
@@ -143,13 +177,16 @@ dump_consts(builtin_t[*] builtins) {
 	printf("#undef AO_SCHEME_BUILTIN_CONSTS\n");
 	printf("struct builtin_func funcs[] = {\n");
 	for (int i = 0; i < dim(builtins); i++) {
-		if (!is_atom(builtins[i])) {
+		if (is_func(builtins[i])) {
+			dump_ifdef(builtins[i]);
 			for (int j = 0; j < dim(builtins[i].lisp_names); j++) {
-				printf ("\t{ .name = \"%s\", .args = AO_SCHEME_FUNC_%s, .func = builtin_%s },\n",
+				printf ("\t{ .feature = \"%s\", .name = \"%s\", .args = AO_SCHEME_FUNC_%s, .func = builtin_%s },\n",
+					builtins[i].feature,
 					builtins[i].lisp_names[j],
 					builtins[i].type,
 					builtins[i].c_name);
 			}
+			dump_endif(builtins[i]);
 		}
 	}
 	printf("};\n");
@@ -161,15 +198,60 @@ dump_atoms(builtin_t[*] builtins) {
 	printf("#ifdef AO_SCHEME_BUILTIN_ATOMS\n");
 	printf("#undef AO_SCHEME_BUILTIN_ATOMS\n");
 	for (int i = 0; i < dim(builtins); i++) {
-		for (int j = 0; j < dim(builtins[i].lisp_names); j++) {
-			printf("#define _ao_scheme_atom_");
-			cify_lisp(builtins[i].lisp_names[j]);
-			printf(" _atom(\"%s\")\n", builtins[i].lisp_names[j]);
+		if (!is_feature(builtins[i])) {
+			for (int j = 0; j < dim(builtins[i].lisp_names); j++) {
+				printf("#define _ao_scheme_atom_");
+				cify_lisp(builtins[i].lisp_names[j]);
+				printf(" _atom(\"%s\")\n", builtins[i].lisp_names[j]);
+			}
 		}
 	}
 	printf("#endif /* AO_SCHEME_BUILTIN_ATOMS */\n");
 }
 
+void
+dump_atom_names(builtin_t[*] builtins) {
+	printf("#ifdef AO_SCHEME_BUILTIN_ATOM_NAMES\n");
+	printf("#undef AO_SCHEME_BUILTIN_ATOM_NAMES\n");
+	printf("static struct builtin_atom atoms[] = {\n");
+	for (int i = 0; i < dim(builtins); i++) {
+		if (is_atom(builtins[i])) {
+			for (int j = 0; j < dim(builtins[i].lisp_names); j++) {
+				printf("\t{ .feature = \"%s\", .name = \"%s\" },\n",
+				       builtins[i].feature,
+				       builtins[i].lisp_names[j]);
+			}
+		}
+	}
+	printf("};\n");
+	printf("#endif /* AO_SCHEME_BUILTIN_ATOM_NAMES */\n");
+}
+
+bool
+has_feature(string[*] features, string feature)
+{
+	for (int i = 0; i < dim(features); i++)
+		if (features[i] == feature)
+			return true;
+	return false;
+}
+
+void
+dump_features(builtin_t[*] builtins) {
+	string[...] features = {};
+	printf("#ifdef AO_SCHEME_BUILTIN_FEATURES\n");
+	for (int i = 0; i < dim(builtins); i++) {
+		if (builtins[i].feature != "all") {
+			string feature = builtins[i].feature;
+			if (!has_feature(features, feature)) {
+				features[dim(features)] = feature;
+				printf("#define AO_SCHEME_FEATURE_%s\n", feature);
+			}
+		}
+	}
+	printf("#endif /* AO_SCHEME_BUILTIN_FEATURES */\n");
+}
+
 void main() {
 	if (dim(argv) < 2) {
 		File::fprintf(stderr, "usage: %s <file>\n", argv[0]);
@@ -177,6 +259,8 @@ void main() {
 	}
 	twixt(file f = File::open(argv[1], "r"); File::close(f)) {
 		builtin_t[*]	builtins = read_builtins(f);
+
+		printf("/* %d builtins */\n", dim(builtins));
 		dump_ids(builtins);
 		dump_casename(builtins);
 		dump_arrayname(builtins);
@@ -184,6 +268,8 @@ void main() {
 		dump_decls(builtins);
 		dump_consts(builtins);
 		dump_atoms(builtins);
+		dump_atom_names(builtins);
+		dump_features(builtins);
 	}
 }
 
diff --git a/src/scheme/ao_scheme_make_const.c b/src/scheme/ao_scheme_make_const.c
index cf42ec52..e34792c4 100644
--- a/src/scheme/ao_scheme_make_const.c
+++ b/src/scheme/ao_scheme_make_const.c
@@ -17,6 +17,7 @@
 #include <ctype.h>
 #include <unistd.h>
 #include <getopt.h>
+#include <stdbool.h>
 
 static struct ao_scheme_builtin *
 ao_scheme_make_builtin(enum ao_scheme_builtin_id func, int args) {
@@ -29,15 +30,25 @@ ao_scheme_make_builtin(enum ao_scheme_builtin_id func, int args) {
 }
 
 struct builtin_func {
-	char	*name;
-	int	args;
+	const char	*feature;
+	const char	*name;
+	int		args;
 	enum ao_scheme_builtin_id	func;
 };
 
+struct builtin_atom {
+	const char	*feature;
+	const char	*name;
+};
+
 #define AO_SCHEME_BUILTIN_CONSTS
+#define AO_SCHEME_BUILTIN_ATOM_NAMES
+
 #include "ao_scheme_builtin.h"
 
-#define N_FUNC (sizeof funcs / sizeof funcs[0])
+#define N_FUNC		(sizeof funcs / sizeof funcs[0])
+
+#define N_ATOM		(sizeof atoms / sizeof atoms[0])
 
 struct ao_scheme_frame	*globals;
 
@@ -69,7 +80,7 @@ ao_fec_crc_byte(uint8_t byte, uint16_t crc)
 	return crc;
 }
 
-uint16_t
+static uint16_t
 ao_fec_crc(const uint8_t *bytes, uint8_t len)
 {
 	uint16_t	crc = AO_FEC_CRC_INIT;
@@ -86,7 +97,7 @@ struct ao_scheme_macro_stack {
 
 struct ao_scheme_macro_stack *macro_stack;
 
-int
+static int
 ao_scheme_macro_push(ao_poly p)
 {
 	struct ao_scheme_macro_stack *m = macro_stack;
@@ -103,7 +114,7 @@ ao_scheme_macro_push(ao_poly p)
 	return 0;
 }
 
-void
+static void
 ao_scheme_macro_pop(void)
 {
 	struct ao_scheme_macro_stack *m = macro_stack;
@@ -130,7 +141,7 @@ void indent(void)
 ao_poly
 ao_has_macro(ao_poly p);
 
-ao_poly
+static ao_poly
 ao_macro_test_get(ao_poly atom)
 {
 	ao_poly	*ref = ao_scheme_atom_ref(atom, NULL);
@@ -139,7 +150,7 @@ ao_macro_test_get(ao_poly atom)
 	return AO_SCHEME_NIL;
 }
 
-ao_poly
+static ao_poly
 ao_is_macro(ao_poly p)
 {
 	struct ao_scheme_builtin	*builtin;
@@ -209,7 +220,7 @@ ao_has_macro(ao_poly p)
 
 		list = cons->cdr;
 		p = AO_SCHEME_NIL;
-		while (list != AO_SCHEME_NIL && ao_scheme_poly_type(list) == AO_SCHEME_CONS) {
+		while (ao_scheme_is_pair(list)) {
 			cons = ao_scheme_poly_cons(list);
 			m = ao_has_macro(cons->car);
 			if (m) {
@@ -228,7 +239,37 @@ ao_has_macro(ao_poly p)
 	return p;
 }
 
-int
+static struct ao_scheme_builtin *
+ao_scheme_get_builtin(ao_poly p)
+{
+	if (ao_scheme_poly_type(p) == AO_SCHEME_BUILTIN)
+		return ao_scheme_poly_builtin(p);
+	return NULL;
+}
+
+struct seen_builtin {
+	struct seen_builtin 		*next;
+	struct ao_scheme_builtin	*builtin;
+};
+
+static struct seen_builtin *seen_builtins;
+
+static int
+ao_scheme_seen_builtin(struct ao_scheme_builtin *b)
+{
+	struct seen_builtin	*s;
+
+	for (s = seen_builtins; s; s = s->next)
+		if (s->builtin == b)
+			return 1;
+	s = malloc (sizeof (struct seen_builtin));
+	s->builtin = b;
+	s->next = seen_builtins;
+	seen_builtins = s;
+	return 0;
+}
+
+static int
 ao_scheme_read_eval_abort(void)
 {
 	ao_poly	in, out = AO_SCHEME_NIL;
@@ -239,7 +280,7 @@ ao_scheme_read_eval_abort(void)
 		out = ao_scheme_eval(in);
 		if (ao_scheme_exception)
 			return 0;
-		ao_scheme_poly_write(out);
+		ao_scheme_poly_write(out, true);
 		putchar ('\n');
 	}
 	return 1;
@@ -248,6 +289,50 @@ ao_scheme_read_eval_abort(void)
 static FILE	*in;
 static FILE	*out;
 
+struct feature {
+	struct feature	*next;
+	char		name[];
+};
+
+static struct feature *enable;
+static struct feature *disable;
+
+static void
+ao_scheme_add_feature(struct feature **list, char *name)
+{
+	struct feature *feature = malloc (sizeof (struct feature) + strlen(name) + 1);
+	strcpy(feature->name, name);
+	feature->next = *list;
+	*list = feature;
+}
+
+static bool
+ao_scheme_has_feature(struct feature *list, const char *name)
+{
+	while (list) {
+		if (!strcmp(list->name, name))
+			return true;
+		list = list->next;
+	}
+	return false;
+}
+
+static void
+ao_scheme_add_features(struct feature **list, const char *names)
+{
+	char	*saveptr = NULL;
+	char	*name;
+	char	*copy = strdup(names);
+	char	*save = copy;
+
+	while ((name = strtok_r(copy, ",", &saveptr)) != NULL) {
+		copy = NULL;
+		if (!ao_scheme_has_feature(*list, name))
+			ao_scheme_add_feature(list, name);
+	}
+	free(save);
+}
+
 int
 ao_scheme_getc(void)
 {
@@ -256,35 +341,46 @@ ao_scheme_getc(void)
 
 static const struct option options[] = {
 	{ .name = "out", .has_arg = 1, .val = 'o' },
+	{ .name = "disable", .has_arg = 1, .val = 'd' },
+	{ .name = "enable", .has_arg = 1, .val = 'e' },
 	{ 0, 0, 0, 0 }
 };
 
 static void usage(char *program)
 {
-	fprintf(stderr, "usage: %s [--out=<output>] [input]\n", program);
+	fprintf(stderr, "usage: %s [--out=<output>] [--disable={feature,...}] [--enable={feature,...} [input]\n", program);
 	exit(1);
 }
 
 int
 main(int argc, char **argv)
 {
-	int	f, o;
+	int	f, o, an;
 	ao_poly	val;
 	struct ao_scheme_atom	*a;
 	struct ao_scheme_builtin	*b;
+	struct feature			*d;
 	int	in_atom = 0;
 	char	*out_name = NULL;
 	int	c;
 	enum ao_scheme_builtin_id	prev_func;
+	enum ao_scheme_builtin_id	target_func;
+	enum ao_scheme_builtin_id	func_map[_builtin_last];
 
 	in = stdin;
 	out = stdout;
 
-	while ((c = getopt_long(argc, argv, "o:", options, NULL)) != -1) {
+	while ((c = getopt_long(argc, argv, "o:d:e:", options, NULL)) != -1) {
 		switch (c) {
 		case 'o':
 			out_name = optarg;
 			break;
+		case 'd':
+			ao_scheme_add_features(&disable, optarg);
+			break;
+		case 'e':
+			ao_scheme_add_features(&enable, optarg);
+			break;
 		default:
 			usage(argv[0]);
 			break;
@@ -298,21 +394,35 @@ main(int argc, char **argv)
 	ao_scheme_bool_get(1);
 
 	prev_func = _builtin_last;
+	target_func = 0;
+	b = NULL;
 	for (f = 0; f < (int) N_FUNC; f++) {
-		if (funcs[f].func != prev_func)
-			b = ao_scheme_make_builtin(funcs[f].func, funcs[f].args);
-		a = ao_scheme_atom_intern(funcs[f].name);
-		ao_scheme_atom_def(ao_scheme_atom_poly(a),
-				 ao_scheme_builtin_poly(b));
+		if (ao_scheme_has_feature(enable, funcs[f].feature) || !ao_scheme_has_feature(disable, funcs[f].feature)) {
+			if (funcs[f].func != prev_func) {
+				prev_func = funcs[f].func;
+				b = ao_scheme_make_builtin(prev_func, funcs[f].args);
+
+				/* Target may have only a subset of
+				 * the enum values; record what those
+				 * values will be here. This obviously
+				 * depends on the functions in the
+				 * array being in the same order as
+				 * the enumeration; which
+				 * ao_scheme_make_builtin ensures.
+				 */
+				func_map[prev_func] = target_func++;
+			}
+			a = ao_scheme_atom_intern((char *) funcs[f].name);
+			ao_scheme_atom_def(ao_scheme_atom_poly(a),
+					   ao_scheme_builtin_poly(b));
+		}
 	}
 
-	/* end of file value */
-	a = ao_scheme_atom_intern("eof");
-	ao_scheme_atom_def(ao_scheme_atom_poly(a),
-			 ao_scheme_atom_poly(a));
-
-	/* 'else' */
-	a = ao_scheme_atom_intern("else");
+	/* atoms */
+	for (an = 0; an < (int) N_ATOM; an++) {
+		if (ao_scheme_has_feature(enable, atoms[an].feature) || !ao_scheme_has_feature(disable, atoms[an].feature))
+			a = ao_scheme_atom_intern((char *) atoms[an].name);
+	}
 
 	if (argv[optind]){
 		in = fopen(argv[optind], "r");
@@ -331,14 +441,22 @@ main(int argc, char **argv)
 
 	for (f = 0; f < ao_scheme_frame_global->num; f++) {
 		struct ao_scheme_frame_vals	*vals = ao_scheme_poly_frame_vals(ao_scheme_frame_global->vals);
+
 		val = ao_has_macro(vals->vals[f].val);
 		if (val != AO_SCHEME_NIL) {
 			printf("error: function %s contains unresolved macro: ",
 			       ao_scheme_poly_atom(vals->vals[f].atom)->name);
-			ao_scheme_poly_write(val);
+			ao_scheme_poly_write(val, true);
 			printf("\n");
 			exit(1);
 		}
+
+		/* Remap builtin enum values to match target set */
+		b = ao_scheme_get_builtin(vals->vals[f].val);
+		if (b != NULL) {
+			if (!ao_scheme_seen_builtin(b))
+				b->func = func_map[b->func];
+		}
 	}
 
 	if (out_name) {
@@ -351,6 +469,9 @@ main(int argc, char **argv)
 
 	fprintf(out, "/* Generated file, do not edit */\n\n");
 
+	for (d = disable; d; d = d->next)
+		fprintf(out, "#undef AO_SCHEME_FEATURE_%s\n", d->name);
+
 	fprintf(out, "#define AO_SCHEME_POOL_CONST %d\n", ao_scheme_top);
 	fprintf(out, "extern const uint8_t ao_scheme_const[AO_SCHEME_POOL_CONST] __attribute__((aligned(4)));\n");
 	fprintf(out, "#define ao_builtin_atoms 0x%04x\n", ao_scheme_atom_poly(ao_scheme_atoms));
@@ -361,32 +482,33 @@ main(int argc, char **argv)
 	fprintf(out, "#define _ao_scheme_bool_true 0x%04x\n", ao_scheme_bool_poly(ao_scheme_true));
 
 	for (a = ao_scheme_atoms; a; a = ao_scheme_poly_atom(a->next)) {
-		char	*n = a->name, c;
+		const char	*n = a->name;
+		char		ch;
 		fprintf(out, "#define _ao_scheme_atom_");
-		while ((c = *n++)) {
-			if (isalnum(c))
-				fprintf(out, "%c", c);
+		while ((ch = *n++)) {
+			if (isalnum(ch))
+				fprintf(out, "%c", ch);
 			else
-				fprintf(out, "%02x", c);
+				fprintf(out, "%02x", ch);
 		}
 		fprintf(out, "  0x%04x\n", ao_scheme_atom_poly(a));
 	}
 	fprintf(out, "#ifdef AO_SCHEME_CONST_BITS\n");
 	fprintf(out, "const uint8_t ao_scheme_const[AO_SCHEME_POOL_CONST] __attribute((aligned(4))) = {");
 	for (o = 0; o < ao_scheme_top; o++) {
-		uint8_t	c;
+		uint8_t	ch;
 		if ((o & 0xf) == 0)
 			fprintf(out, "\n\t");
 		else
 			fprintf(out, " ");
-		c = ao_scheme_const[o];
+		ch = ao_scheme_const[o];
 		if (!in_atom)
 			in_atom = is_atom(o);
 		if (in_atom) {
-			fprintf(out, " '%c',", c);
+			fprintf(out, " '%c',", ch);
 			in_atom--;
 		} else {
-			fprintf(out, "0x%02x,", c);
+			fprintf(out, "0x%02x,", ch);
 		}
 	}
 	fprintf(out, "\n};\n");
diff --git a/src/scheme/ao_scheme_mem.c b/src/scheme/ao_scheme_mem.c
index 45d4de98..c9215072 100644
--- a/src/scheme/ao_scheme_mem.c
+++ b/src/scheme/ao_scheme_mem.c
@@ -41,11 +41,47 @@ uint8_t	ao_scheme_pool[AO_SCHEME_POOL + AO_SCHEME_POOL_EXTRA] __attribute__((ali
 #define DBG_MEM_STATS	DBG_MEM
 #endif
 
+#define DBG_MEM_STACK	0
+#if DBG_MEM_STACK
+char	*mem_collect_stack;
+int64_t	mem_collect_max_depth;
+
+static void
+ao_scheme_check_stack(void)
+{
+	char	x;
+	int64_t	depth;
+
+	depth = mem_collect_stack - &x;
+	if (depth > mem_collect_max_depth)
+		mem_collect_max_depth = depth;
+}
+
+static void
+_ao_scheme_reset_stack(char *x)
+{
+	mem_collect_stack = x;
+//	mem_collect_max_depth = 0;
+}
+#define ao_scheme_declare_stack	char x;
+#define ao_scheme_reset_stack() _ao_scheme_reset_stack(&x)
+#else
+#define ao_scheme_check_stack()
+#define ao_scheme_declare_stack
+#define ao_scheme_reset_stack()
+#endif
+
+#if DBG_MEM
+#define DBG_MEM_RECORD	1
+#endif
+
 #if DBG_MEM
 int dbg_move_depth;
 int dbg_mem = DBG_MEM_START;
 int dbg_validate = 0;
+#endif
 
+#if DBG_MEM_RECORD
 struct ao_scheme_record {
 	struct ao_scheme_record		*next;
 	const struct ao_scheme_type	*type;
@@ -99,9 +135,9 @@ ao_scheme_record_save(void)
 }
 
 static void
-ao_scheme_record_compare(char *where,
-		       struct ao_scheme_record *a,
-		       struct ao_scheme_record *b)
+ao_scheme_record_compare(const char *where,
+			 struct ao_scheme_record *a,
+			 struct ao_scheme_record *b)
 {
 	while (a && b) {
 		if (a->type != b->type || a->size != b->size) {
@@ -138,6 +174,7 @@ ao_scheme_record_compare(char *where,
 
 #else
 #define ao_scheme_record_reset()
+#define ao_scheme_record(t,a,s)
 #endif
 
 uint8_t	ao_scheme_exception;
@@ -147,43 +184,34 @@ struct ao_scheme_root {
 	void				**addr;
 };
 
-static struct ao_scheme_cons 	*save_cons[2];
-static char			*save_string[2];
-static struct ao_scheme_frame	*save_frame[1];
-static ao_poly			save_poly[3];
+#define AO_SCHEME_NUM_STASH	6
+static ao_poly			stash_poly[AO_SCHEME_NUM_STASH];
+static int			stash_poly_ptr;
 
 static const struct ao_scheme_root	ao_scheme_root[] = {
 	{
-		.type = &ao_scheme_cons_type,
-		.addr = (void **) &save_cons[0],
-	},
-	{
-		.type = &ao_scheme_cons_type,
-		.addr = (void **) &save_cons[1],
-	},
-	{
-		.type = &ao_scheme_string_type,
-		.addr = (void **) &save_string[0],
+		.type = NULL,
+		.addr = (void **) (void *) &stash_poly[0]
 	},
 	{
-		.type = &ao_scheme_string_type,
-		.addr = (void **) &save_string[1],
+		.type = NULL,
+		.addr = (void **) (void *) &stash_poly[1]
 	},
 	{
-		.type = &ao_scheme_frame_type,
-		.addr = (void **) &save_frame[0],
+		.type = NULL,
+		.addr = (void **) (void *) &stash_poly[2]
 	},
 	{
 		.type = NULL,
-		.addr = (void **) (void *) &save_poly[0]
+		.addr = (void **) (void *) &stash_poly[3]
 	},
 	{
 		.type = NULL,
-		.addr = (void **) (void *) &save_poly[1]
+		.addr = (void **) (void *) &stash_poly[4]
 	},
 	{
 		.type = NULL,
-		.addr = (void **) (void *) &save_poly[2]
+		.addr = (void **) (void *) &stash_poly[5]
 	},
 	{
 		.type = &ao_scheme_atom_type,
@@ -250,6 +278,10 @@ static const void ** const ao_scheme_cache[] = {
 
 #define AO_SCHEME_BUSY_SIZE	((AO_SCHEME_POOL + 31) / 32)
 
+static int	ao_scheme_printing, ao_scheme_print_cleared;
+#if DBG_MEM
+static int	ao_scheme_collecting;
+#endif
 static uint8_t	ao_scheme_busy[AO_SCHEME_BUSY_SIZE];
 static uint8_t	ao_scheme_cons_note[AO_SCHEME_BUSY_SIZE];
 static uint8_t	ao_scheme_cons_last[AO_SCHEME_BUSY_SIZE];
@@ -272,7 +304,7 @@ static struct ao_scheme_chunk ao_scheme_chunk[AO_SCHEME_NCHUNK];
 /* Offset of an address within the pool. */
 static inline uint16_t pool_offset(void *addr) {
 #if DBG_MEM
-	if (!AO_SCHEME_IS_POOL(addr))
+	if (!ao_scheme_is_pool_addr(addr))
 		ao_scheme_abort();
 #endif
 	return ((uint8_t *) addr) - ao_scheme_pool;
@@ -281,6 +313,7 @@ static inline uint16_t pool_offset(void *addr) {
 static inline void mark(uint8_t *tag, int offset) {
 	int	byte = offset >> 5;
 	int	bit = (offset >> 2) & 7;
+	ao_scheme_check_stack();
 	tag[byte] |= (1 << bit);
 }
 
@@ -303,7 +336,7 @@ static inline int limit(int offset) {
 	return min(AO_SCHEME_POOL, max(offset, 0));
 }
 
-static void
+static inline void
 note_cons(uint16_t offset)
 {
 	MDBG_MOVE("note cons %d\n", offset);
@@ -335,6 +368,7 @@ static void
 note_chunk(uint16_t offset, uint16_t size)
 {
 	int l;
+	int end;
 
 	if (offset < chunk_low || chunk_high <= offset)
 		return;
@@ -354,10 +388,13 @@ note_chunk(uint16_t offset, uint16_t size)
 	/* Off the left side */
 	if (l == 0 && chunk_last && offset > ao_scheme_chunk[0].old_offset)
 		ao_scheme_abort();
+
+	if (l < chunk_last && ao_scheme_chunk[l].old_offset == offset)
+		ao_scheme_abort();
 #endif
 
 	/* Shuffle existing entries right */
-	int end = min(AO_SCHEME_NCHUNK, chunk_last + 1);
+	end = min(AO_SCHEME_NCHUNK, chunk_last + 1);
 
 	memmove(&ao_scheme_chunk[l+1],
 		&ao_scheme_chunk[l],
@@ -433,20 +470,19 @@ static void
 dump_busy(void)
 {
 	int	i;
-	MDBG_MOVE("busy:");
+	printf("busy:");
 	for (i = 0; i < ao_scheme_top; i += 4) {
 		if ((i & 0xff) == 0) {
-			MDBG_MORE("\n");
-			MDBG_MOVE("%s", "");
+			printf("\n\t");
 		}
 		else if ((i & 0x1f) == 0)
-			MDBG_MORE(" ");
+			printf(" ");
 		if (busy(ao_scheme_busy, i))
-			MDBG_MORE("*");
+			printf("*");
 		else
-			MDBG_MORE("-");
+			printf("-");
 	}
-	MDBG_MORE ("\n");
+	printf ("\n");
 }
 #define DUMP_BUSY()	dump_busy()
 #else
@@ -456,7 +492,9 @@ dump_busy(void)
 static const struct ao_scheme_type * const ao_scheme_types[AO_SCHEME_NUM_TYPE] = {
 	[AO_SCHEME_CONS] = &ao_scheme_cons_type,
 	[AO_SCHEME_INT] = NULL,
-	[AO_SCHEME_STRING] = &ao_scheme_string_type,
+#ifdef AO_SCHEME_FEATURE_BIGINT
+	[AO_SCHEME_BIGINT] = &ao_scheme_bigint_type,
+#endif
 	[AO_SCHEME_OTHER] = (void *) 0x1,
 	[AO_SCHEME_ATOM] = &ao_scheme_atom_type,
 	[AO_SCHEME_BUILTIN] = &ao_scheme_builtin_type,
@@ -465,12 +503,22 @@ static const struct ao_scheme_type * const ao_scheme_types[AO_SCHEME_NUM_TYPE] =
 	[AO_SCHEME_LAMBDA] = &ao_scheme_lambda_type,
 	[AO_SCHEME_STACK] = &ao_scheme_stack_type,
 	[AO_SCHEME_BOOL] = &ao_scheme_bool_type,
-	[AO_SCHEME_BIGINT] = &ao_scheme_bigint_type,
+	[AO_SCHEME_STRING] = &ao_scheme_string_type,
+#ifdef AO_SCHEME_FEATURE_FLOAT
 	[AO_SCHEME_FLOAT] = &ao_scheme_float_type,
+#endif
+#ifdef AO_SCHEME_FEATURE_VECTOR
 	[AO_SCHEME_VECTOR] = &ao_scheme_vector_type,
+#endif
 };
 
 static int
+ao_scheme_mark(const struct ao_scheme_type *type, void *addr);
+
+static int
+ao_scheme_move(const struct ao_scheme_type *type, void **ref);
+
+static int
 ao_scheme_mark_ref(const struct ao_scheme_type *type, void **ref)
 {
 	return ao_scheme_mark(type, *ref);
@@ -489,26 +537,39 @@ uint64_t ao_scheme_loops[2];
 #endif
 
 int ao_scheme_last_top;
+int ao_scheme_collect_counts;
 
 int
 ao_scheme_collect(uint8_t style)
 {
+	ao_scheme_declare_stack
 	int	i;
 	int	top;
 #if DBG_MEM_STATS
 	int	loops = 0;
 #endif
-#if DBG_MEM
+#if DBG_MEM_RECORD
 	struct ao_scheme_record	*mark_record = NULL, *move_record = NULL;
-
-	MDBG_MOVE("collect %d\n", ao_scheme_collects[style]);
 #endif
+	MDBG_MOVE("collect %lu\n", ao_scheme_collects[style]);
+
 	MDBG_DO(ao_scheme_frame_write(ao_scheme_frame_poly(ao_scheme_frame_global)));
+	MDBG_DO(++ao_scheme_collecting);
+
+	ao_scheme_reset_stack();
 
 	/* The first time through, we're doing a full collect */
 	if (ao_scheme_last_top == 0)
 		style = AO_SCHEME_COLLECT_FULL;
 
+	/* One in a while, just do a full collect */
+
+	if (ao_scheme_collect_counts >= 128)
+		style = AO_SCHEME_COLLECT_FULL;
+
+	if (style == AO_SCHEME_COLLECT_FULL)
+		ao_scheme_collect_counts = 0;
+
 	/* Clear references to all caches */
 	for (i = 0; i < (int) AO_SCHEME_CACHE; i++)
 		*ao_scheme_cache[i] = NULL;
@@ -518,15 +579,12 @@ ao_scheme_collect(uint8_t style)
 		chunk_low = top = ao_scheme_last_top;
 	}
 	for (;;) {
-#if DBG_MEM_STATS
-		loops++;
-#endif
 		MDBG_MOVE("move chunks from %d to %d\n", chunk_low, top);
 		/* Find the sizes of the first chunk of objects to move */
 		reset_chunks();
 		walk(ao_scheme_mark_ref, ao_scheme_poly_mark_ref);
-#if DBG_MEM
 
+#if DBG_MEM_RECORD
 		ao_scheme_record_free(mark_record);
 		mark_record = ao_scheme_record_save();
 		if (mark_record && move_record)
@@ -538,7 +596,6 @@ ao_scheme_collect(uint8_t style)
 		/* Find the first moving object */
 		for (i = 0; i < chunk_last; i++) {
 			uint16_t	size = ao_scheme_chunk[i].size;
-
 #if DBG_MEM
 			if (!size)
 				ao_scheme_abort();
@@ -557,6 +614,20 @@ ao_scheme_collect(uint8_t style)
 			top += size;
 		}
 
+		/* Short-circuit the rest of the loop when all of the
+		 * found objects aren't moving. This isn't strictly
+		 * necessary as the rest of the loop is structured to
+		 * work in this case, but GCC 7.2.0 with optimization
+		 * greater than 2 generates incorrect code for this...
+		 */
+		if (i == AO_SCHEME_NCHUNK) {
+			chunk_low = chunk_high;
+#if DBG_MEM_STATS
+			loops++;
+#endif
+			continue;
+		}
+
 		/*
 		 * Limit amount of chunk array used in mapping moves
 		 * to the active region
@@ -590,7 +661,7 @@ ao_scheme_collect(uint8_t style)
 			/* Relocate all references to the objects */
 			walk(ao_scheme_move, ao_scheme_poly_move);
 
-#if DBG_MEM
+#if DBG_MEM_RECORD
 			ao_scheme_record_free(move_record);
 			move_record = ao_scheme_record_save();
 			if (mark_record && move_record)
@@ -598,6 +669,9 @@ ao_scheme_collect(uint8_t style)
 #endif
 		}
 
+#if DBG_MEM_STATS
+		loops++;
+#endif
 		/* If we ran into the end of the heap, then
 		 * there's no need to keep walking
 		 */
@@ -622,6 +696,10 @@ ao_scheme_collect(uint8_t style)
 	MDBG_DO(memset(ao_scheme_chunk, '\0', sizeof (ao_scheme_chunk));
 		walk(ao_scheme_mark_ref, ao_scheme_poly_mark_ref));
 
+#if DBG_MEM_STACK
+	fprintf(stderr, "max collect stack depth %lu\n", mem_collect_max_depth);
+#endif
+	MDBG_DO(--ao_scheme_collecting);
 	return AO_SCHEME_POOL - ao_scheme_top;
 }
 
@@ -636,7 +714,7 @@ ao_scheme_cons_check(struct ao_scheme_cons *cons)
 	reset_chunks();
 	walk(ao_scheme_mark_ref, ao_scheme_poly_mark_ref);
 	while (cons) {
-		if (!AO_SCHEME_IS_POOL(cons))
+		if (!ao_scheme_is_pool_addr(cons))
 			break;
 		offset = pool_offset(cons);
 		if (busy(ao_scheme_busy, offset)) {
@@ -657,28 +735,6 @@ ao_scheme_cons_check(struct ao_scheme_cons *cons)
 
 
 /*
- * Mark a block of memory with an explicit size
- */
-
-int
-ao_scheme_mark_block(void *addr, int size)
-{
-	int offset;
-	if (!AO_SCHEME_IS_POOL(addr))
-		return 1;
-
-	offset = pool_offset(addr);
-	MDBG_MOVE("mark memory %d\n", MDBG_OFFSET(addr));
-	if (busy(ao_scheme_busy, offset)) {
-		MDBG_MOVE("already marked\n");
-		return 1;
-	}
-	mark(ao_scheme_busy, offset);
-	note_chunk(offset, size);
-	return 0;
-}
-
-/*
  * Note a reference to memory and collect information about a few
  * object sizes at a time
  */
@@ -687,7 +743,7 @@ int
 ao_scheme_mark_memory(const struct ao_scheme_type *type, void *addr)
 {
 	int offset;
-	if (!AO_SCHEME_IS_POOL(addr))
+	if (!ao_scheme_is_pool_addr(addr))
 		return 1;
 
 	offset = pool_offset(addr);
@@ -704,7 +760,7 @@ ao_scheme_mark_memory(const struct ao_scheme_type *type, void *addr)
 /*
  * Mark an object and all that it refereces
  */
-int
+static int
 ao_scheme_mark(const struct ao_scheme_type *type, void *addr)
 {
 	int ret;
@@ -731,6 +787,7 @@ ao_scheme_poly_mark(ao_poly p, uint8_t do_note_cons)
 {
 	uint8_t type;
 	void	*addr;
+	int	ret;
 
 	type = ao_scheme_poly_base_type(p);
 
@@ -738,23 +795,33 @@ ao_scheme_poly_mark(ao_poly p, uint8_t do_note_cons)
 		return 1;
 
 	addr = ao_scheme_ref(p);
-	if (!AO_SCHEME_IS_POOL(addr))
+	if (!ao_scheme_is_pool_addr(addr))
 		return 1;
 
 	if (type == AO_SCHEME_CONS && do_note_cons) {
 		note_cons(pool_offset(addr));
 		return 1;
 	} else {
+		const struct ao_scheme_type *lisp_type;
+
 		if (type == AO_SCHEME_OTHER)
 			type = ao_scheme_other_type(addr);
 
-		const struct ao_scheme_type *lisp_type = ao_scheme_types[type];
+		lisp_type = ao_scheme_types[type];
 #if DBG_MEM
 		if (!lisp_type)
 			ao_scheme_abort();
 #endif
 
-		return ao_scheme_mark(lisp_type, addr);
+		MDBG_MOVE("mark %d\n", MDBG_OFFSET(addr));
+		MDBG_MOVE_IN();
+		ret = ao_scheme_mark_memory(lisp_type, addr);
+		if (!ret) {
+			MDBG_MOVE("mark recurse\n");
+			lisp_type->mark(addr);
+		}
+		MDBG_MOVE_OUT();
+		return ret;
 	}
 }
 
@@ -788,7 +855,7 @@ ao_scheme_move_memory(const struct ao_scheme_type *type, void **ref)
 	void		*addr = *ref;
 	uint16_t	offset, orig_offset;
 
-	if (!AO_SCHEME_IS_POOL(addr))
+	if (!ao_scheme_is_pool_addr(addr))
 		return 1;
 
 	(void) type;
@@ -798,7 +865,7 @@ ao_scheme_move_memory(const struct ao_scheme_type *type, void **ref)
 	offset = move_map(orig_offset);
 	if (offset != orig_offset) {
 		MDBG_MOVE("update ref %d %d -> %d\n",
-			  AO_SCHEME_IS_POOL(ref) ? MDBG_OFFSET(ref) : -1,
+			  ao_scheme_is_pool_addr(ref) ? MDBG_OFFSET(ref) : -1,
 			  orig_offset, offset);
 		*ref = ao_scheme_pool + offset;
 	}
@@ -807,11 +874,11 @@ ao_scheme_move_memory(const struct ao_scheme_type *type, void **ref)
 		return 1;
 	}
 	mark(ao_scheme_busy, offset);
-	MDBG_DO(ao_scheme_record(type, addr, ao_scheme_size(type, addr)));
+	ao_scheme_record(type, addr, ao_scheme_size(type, addr));
 	return 0;
 }
 
-int
+static int
 ao_scheme_move(const struct ao_scheme_type *type, void **ref)
 {
 	int ret;
@@ -829,53 +896,59 @@ ao_scheme_move(const struct ao_scheme_type *type, void **ref)
 int
 ao_scheme_poly_move(ao_poly *ref, uint8_t do_note_cons)
 {
-	uint8_t		type;
 	ao_poly		p = *ref;
 	int		ret;
 	void		*addr;
 	uint16_t	offset, orig_offset;
-	uint8_t		base_type;
 
-	base_type = type = ao_scheme_poly_base_type(p);
-
-	if (type == AO_SCHEME_INT)
+	if (ao_scheme_poly_base_type(p) == AO_SCHEME_INT)
 		return 1;
 
 	addr = ao_scheme_ref(p);
-	if (!AO_SCHEME_IS_POOL(addr))
+	if (!ao_scheme_is_pool_addr(addr))
 		return 1;
 
 	orig_offset = pool_offset(addr);
 	offset = move_map(orig_offset);
 
-	if (type == AO_SCHEME_CONS && do_note_cons) {
+	if (ao_scheme_poly_base_type(p) == AO_SCHEME_CONS && do_note_cons) {
 		note_cons(orig_offset);
 		ret = 1;
 	} else {
+		uint8_t type = ao_scheme_poly_base_type(p);
+		const struct ao_scheme_type *lisp_type;
+
 		if (type == AO_SCHEME_OTHER)
 			type = ao_scheme_other_type(ao_scheme_pool + offset);
 
-		const struct ao_scheme_type *lisp_type = ao_scheme_types[type];
+		lisp_type = ao_scheme_types[type];
 #if DBG_MEM
 		if (!lisp_type)
 			ao_scheme_abort();
 #endif
-
-		ret = ao_scheme_move(lisp_type, &addr);
+		/* inline ao_scheme_move to save stack space */
+		MDBG_MOVE("move object %d\n", MDBG_OFFSET(addr));
+		MDBG_MOVE_IN();
+		ret = ao_scheme_move_memory(lisp_type, &addr);
+		if (!ret) {
+			MDBG_MOVE("move recurse\n");
+			lisp_type->move(addr);
+		}
+		MDBG_MOVE_OUT();
 	}
 
 	/* Re-write the poly value */
 	if (offset != orig_offset) {
-		ao_poly np = ao_scheme_poly(ao_scheme_pool + offset, base_type);
+		ao_poly np = ao_scheme_poly(ao_scheme_pool + offset, ao_scheme_poly_base_type(p));
 		MDBG_MOVE("poly %d moved %d -> %d\n",
-			  type, orig_offset, offset);
+			  ao_scheme_poly_type(np), orig_offset, offset);
 		*ref = np;
 	}
 	return ret;
 }
 
 #if DBG_MEM
-void
+static void
 ao_scheme_validate(void)
 {
 	chunk_low = 0;
@@ -909,61 +982,80 @@ ao_scheme_alloc(int size)
 }
 
 void
-ao_scheme_cons_stash(int id, struct ao_scheme_cons *cons)
+ao_scheme_poly_stash(ao_poly p)
 {
-	assert(save_cons[id] == 0);
-	save_cons[id] = cons;
+	assert(stash_poly_ptr < AO_SCHEME_NUM_STASH);
+	stash_poly[stash_poly_ptr++] = p;
 }
 
-struct ao_scheme_cons *
-ao_scheme_cons_fetch(int id)
+ao_poly
+ao_scheme_poly_fetch(void)
 {
-	struct ao_scheme_cons *cons = save_cons[id];
-	save_cons[id] = NULL;
-	return cons;
-}
+	ao_poly	p;
 
-void
-ao_scheme_poly_stash(int id, ao_poly poly)
-{
-	assert(save_poly[id] == AO_SCHEME_NIL);
-	save_poly[id] = poly;
+	assert (stash_poly_ptr > 0);
+	p = stash_poly[--stash_poly_ptr];
+	stash_poly[stash_poly_ptr] = AO_SCHEME_NIL;
+	return p;
 }
 
-ao_poly
-ao_scheme_poly_fetch(int id)
+int
+ao_scheme_print_mark_addr(void *addr)
 {
-	ao_poly poly = save_poly[id];
-	save_poly[id] = AO_SCHEME_NIL;
-	return poly;
+	int	offset;
+
+#if DBG_MEM
+	if (ao_scheme_collecting)
+		ao_scheme_abort();
+#endif
+
+	if (!ao_scheme_is_pool_addr(addr))
+		return 0;
+
+	if (!ao_scheme_print_cleared) {
+		ao_scheme_print_cleared = 1;
+		memset(ao_scheme_busy, '\0', sizeof (ao_scheme_busy));
+	}
+	offset = pool_offset(addr);
+	if (busy(ao_scheme_busy, offset))
+		return 1;
+	mark(ao_scheme_busy, offset);
+	return 0;
 }
 
 void
-ao_scheme_string_stash(int id, char *string)
+ao_scheme_print_clear_addr(void *addr)
 {
-	assert(save_string[id] == NULL);
-	save_string[id] = string;
-}
+	int	offset;
 
-char *
-ao_scheme_string_fetch(int id)
-{
-	char *string = save_string[id];
-	save_string[id] = NULL;
-	return string;
+#if DBG_MEM
+	if (ao_scheme_collecting)
+		ao_scheme_abort();
+#endif
+
+	if (!ao_scheme_is_pool_addr(addr))
+		return;
+
+	if (!ao_scheme_print_cleared)
+		return;
+	offset = pool_offset(addr);
+	clear(ao_scheme_busy, offset);
 }
 
+/* Notes that printing has started */
 void
-ao_scheme_frame_stash(int id, struct ao_scheme_frame *frame)
+ao_scheme_print_start(void)
 {
-	assert(save_frame[id] == NULL);
-	save_frame[id] = frame;
+	ao_scheme_printing++;
 }
 
-struct ao_scheme_frame *
-ao_scheme_frame_fetch(int id)
+/* Notes that printing has ended. Returns 1 if printing is still going on */
+int
+ao_scheme_print_stop(void)
 {
-	struct ao_scheme_frame *frame = save_frame[id];
-	save_frame[id] = NULL;
-	return frame;
+	ao_scheme_printing--;
+	if (ao_scheme_printing != 0)
+		return 1;
+	ao_scheme_print_cleared = 0;
+	return 0;
 }
diff --git a/src/scheme/ao_scheme_poly.c b/src/scheme/ao_scheme_poly.c
index 553585db..0cffc196 100644
--- a/src/scheme/ao_scheme_poly.c
+++ b/src/scheme/ao_scheme_poly.c
@@ -14,92 +14,41 @@
 
 #include "ao_scheme.h"
 
-struct ao_scheme_funcs {
-	void (*write)(ao_poly);
-	void (*display)(ao_poly);
-};
+static void ao_scheme_invalid_write(ao_poly p, bool write) {
+	printf("??? type %d poly 0x%04x ???", ao_scheme_poly_type (p), p);
+	(void) write;
+	ao_scheme_abort();
+}
 
-static const struct ao_scheme_funcs ao_scheme_funcs[AO_SCHEME_NUM_TYPE] = {
-	[AO_SCHEME_CONS] = {
-		.write = ao_scheme_cons_write,
-		.display = ao_scheme_cons_display,
-	},
-	[AO_SCHEME_STRING] = {
-		.write = ao_scheme_string_write,
-		.display = ao_scheme_string_display,
-	},
-	[AO_SCHEME_INT] = {
-		.write = ao_scheme_int_write,
-		.display = ao_scheme_int_write,
-	},
-	[AO_SCHEME_ATOM] = {
-		.write = ao_scheme_atom_write,
-		.display = ao_scheme_atom_write,
-	},
-	[AO_SCHEME_BUILTIN] = {
-		.write = ao_scheme_builtin_write,
-		.display = ao_scheme_builtin_write,
-	},
-	[AO_SCHEME_FRAME] = {
-		.write = ao_scheme_frame_write,
-		.display = ao_scheme_frame_write,
-	},
-	[AO_SCHEME_FRAME_VALS] = {
-		.write = NULL,
-		.display = NULL,
-	},
-	[AO_SCHEME_LAMBDA] = {
-		.write = ao_scheme_lambda_write,
-		.display = ao_scheme_lambda_write,
-	},
-	[AO_SCHEME_STACK] = {
-		.write = ao_scheme_stack_write,
-		.display = ao_scheme_stack_write,
-	},
-	[AO_SCHEME_BOOL] = {
-		.write = ao_scheme_bool_write,
-		.display = ao_scheme_bool_write,
-	},
-	[AO_SCHEME_BIGINT] = {
-		.write = ao_scheme_bigint_write,
-		.display = ao_scheme_bigint_write,
-	},
-	[AO_SCHEME_FLOAT] = {
-		.write = ao_scheme_float_write,
-		.display = ao_scheme_float_write,
-	},
-	[AO_SCHEME_VECTOR] = {
-		.write = ao_scheme_vector_write,
-		.display = ao_scheme_vector_display
-	},
+static void (*const ao_scheme_write_funcs[AO_SCHEME_NUM_TYPE]) (ao_poly p, bool write) = {
+	[AO_SCHEME_CONS] = ao_scheme_cons_write,
+#ifdef AO_SCHEME_FEATURE_BIGINT
+	[AO_SCHEME_BIGINT] = ao_scheme_bigint_write,
+#endif
+	[AO_SCHEME_INT] = ao_scheme_int_write,
+	[AO_SCHEME_ATOM] = ao_scheme_atom_write,
+	[AO_SCHEME_BUILTIN] = ao_scheme_builtin_write,
+	[AO_SCHEME_FRAME] = ao_scheme_frame_write,
+	[AO_SCHEME_FRAME_VALS] = ao_scheme_invalid_write,
+	[AO_SCHEME_LAMBDA] = ao_scheme_lambda_write,
+	[AO_SCHEME_STACK] = ao_scheme_stack_write,
+	[AO_SCHEME_BOOL] = ao_scheme_bool_write,
+	[AO_SCHEME_STRING] = ao_scheme_string_write,
+#ifdef AO_SCHEME_FEATURE_FLOAT
+	[AO_SCHEME_FLOAT] = ao_scheme_float_write,
+#endif
+#ifdef AO_SCHEME_FEATURE_VECTOR
+	[AO_SCHEME_VECTOR] = ao_scheme_vector_write,
+#endif
 };
 
-static const struct ao_scheme_funcs *
-funcs(ao_poly p)
+void (*ao_scheme_poly_write_func(ao_poly p))(ao_poly p, bool write)
 {
 	uint8_t	type = ao_scheme_poly_type(p);
 
 	if (type < AO_SCHEME_NUM_TYPE)
-		return &ao_scheme_funcs[type];
-	return NULL;
-}
-
-void
-ao_scheme_poly_write(ao_poly p)
-{
-	const struct ao_scheme_funcs *f = funcs(p);
-
-	if (f && f->write)
-		f->write(p);
-}
-
-void
-ao_scheme_poly_display(ao_poly p)
-{
-	const struct ao_scheme_funcs *f = funcs(p);
-
-	if (f && f->display)
-		f->display(p);
+		return ao_scheme_write_funcs[type];
+	return ao_scheme_invalid_write;
 }
 
 void *
@@ -116,7 +65,7 @@ ao_scheme_poly(const void *addr, ao_poly type) {
 	const uint8_t	*a = addr;
 	if (a == NULL)
 		return AO_SCHEME_NIL;
-	if (AO_SCHEME_IS_CONST(a))
+	if (ao_scheme_is_const_addr(a))
 		return AO_SCHEME_CONST | (a - ao_scheme_const + 4) | type;
 	return (a - ao_scheme_pool + 4) | type;
 }
diff --git a/src/scheme/ao_scheme_read.c b/src/scheme/ao_scheme_read.c
index 9ed54b9f..e93466fc 100644
--- a/src/scheme/ao_scheme_read.c
+++ b/src/scheme/ao_scheme_read.c
@@ -62,7 +62,7 @@ static const uint16_t	lex_classes[128] = {
  	PRINTABLE|SPECIAL,	/* ) */
  	PRINTABLE,		/* * */
  	PRINTABLE|SIGN,		/* + */
- 	PRINTABLE|SPECIAL,	/* , */
+ 	PRINTABLE|SPECIAL_QUASI,	/* , */
  	PRINTABLE|SIGN,		/* - */
  	PRINTABLE|DOTC|FLOATC,	/* . */
  	PRINTABLE,		/* / */
@@ -114,7 +114,7 @@ static const uint16_t	lex_classes[128] = {
 	PRINTABLE,		/*  ] */
 	PRINTABLE,		/*  ^ */
 	PRINTABLE,		/*  _ */
-  	PRINTABLE|SPECIAL,	/*  ` */
+  	PRINTABLE|SPECIAL_QUASI,	/*  ` */
 	PRINTABLE,		/*  a */
 	PRINTABLE,		/*  b */
 	PRINTABLE,		/*  c */
@@ -244,12 +244,13 @@ lex_quoted(void)
 	}
 }
 
+#ifndef AO_SCHEME_TOKEN_MAX
 #define AO_SCHEME_TOKEN_MAX	128
+#endif
 
 static char	token_string[AO_SCHEME_TOKEN_MAX];
 static int32_t	token_int;
 static int	token_len;
-static float	token_float;
 
 static inline void add_token(int c) {
 	if (c && token_len < AO_SCHEME_TOKEN_MAX - 1)
@@ -265,6 +266,9 @@ static inline void end_token(void) {
 	token_string[token_len] = '\0';
 }
 
+#ifdef AO_SCHEME_FEATURE_FLOAT
+static float	token_float;
+
 struct namedfloat {
 	const char	*name;
 	float		value;
@@ -278,6 +282,7 @@ static const struct namedfloat namedfloats[] = {
 };
 
 #define NUM_NAMED_FLOATS	(sizeof namedfloats / sizeof namedfloats[0])
+#endif
 
 static int
 _lex(void)
@@ -315,6 +320,7 @@ _lex(void)
 				return QUOTE;
 			case '.':
 				return DOT;
+#ifdef AO_SCHEME_FEATURE_QUASI
 			case '`':
 				return QUASIQUOTE;
 			case ',':
@@ -327,6 +333,7 @@ _lex(void)
 					lex_unget(c);
 					return UNQUOTE;
 				}
+#endif
 			}
 		}
 		if (lex_class & POUND) {
@@ -340,8 +347,10 @@ _lex(void)
 				add_token(c);
 				end_token();
 				return BOOL;
+#ifdef AO_SCHEME_FEATURE_VECTOR
 			case '(':
 				return OPEN_VECTOR;
+#endif
 			case '\\':
 				for (;;) {
 					int alphabetic;
@@ -393,23 +402,23 @@ _lex(void)
 			}
 		}
 		if (lex_class & PRINTABLE) {
-			int	isfloat;
-			int	hasdigit;
-			int	isneg;
-			int	isint;
-			int	epos;
-
-			isfloat = 1;
-			isint = 1;
-			hasdigit = 0;
+#ifdef AO_SCHEME_FEATURE_FLOAT
+			int	isfloat = 1;
+			int	epos = 0;
+#endif
+			int	hasdigit = 0;
+			int	isneg = 0;
+			int	isint = 1;
+
 			token_int = 0;
-			isneg = 0;
-			epos = 0;
 			for (;;) {
 				if (!(lex_class & NUMBER)) {
 					isint = 0;
+#ifdef AO_SCHEME_FEATURE_FLOAT
 					isfloat = 0;
+#endif
 				} else {
+#ifdef AO_SCHEME_FEATURE_FLOAT
 					if (!(lex_class & INTEGER))
 						isint = 0;
  					if (token_len != epos &&
@@ -418,8 +427,10 @@ _lex(void)
 						isint = 0;
 						isfloat = 0;
 					}
+#endif
 					if (c == '-')
 						isneg = 1;
+#ifdef AO_SCHEME_FEATURE_FLOAT
 					if (c == '.' && epos != 0)
 						isfloat = 0;
 					if (c == 'e' || c == 'E') {
@@ -428,6 +439,7 @@ _lex(void)
 						else
 							epos = token_len + 1;
 					}
+#endif
 					if (lex_class & DIGIT) {
 						hasdigit = 1;
 						if (isint)
@@ -436,8 +448,14 @@ _lex(void)
 				}
 				add_token (c);
 				c = lexc ();
-				if ((lex_class & (NOTNAME)) && (c != '.' || !isfloat)) {
+				if ((lex_class & (NOTNAME))
+#ifdef AO_SCHEME_FEATURE_FLOAT
+				    && (c != '.' || !isfloat)
+#endif
+					) {
+#ifdef AO_SCHEME_FEATURE_FLOAT
 					unsigned int u;
+#endif
 //					if (lex_class & ENDOFFILE)
 //						clearerr (f);
 					lex_unget(c);
@@ -447,6 +465,7 @@ _lex(void)
 							token_int = -token_int;
 						return NUM;
 					}
+#ifdef AO_SCHEME_FEATURE_FLOAT
 					if (isfloat && hasdigit) {
 						token_float = strtof(token_string, NULL);
 						return FLOAT;
@@ -456,6 +475,7 @@ _lex(void)
 							token_float = namedfloats[u].value;
 							return FLOAT;
 						}
+#endif
 					return NAME;
 				}
 			}
@@ -490,7 +510,7 @@ push_read_stack(int read_state)
 	RDBG_IN();
 	if (ao_scheme_read_list) {
 		ao_scheme_read_stack = ao_scheme_cons_cons(ao_scheme_cons_poly(ao_scheme_read_cons),
-						       ao_scheme__cons(ao_scheme_int_poly(read_state),
+						       ao_scheme_cons(ao_scheme_int_poly(read_state),
 								     ao_scheme_cons_poly(ao_scheme_read_stack)));
 		if (!ao_scheme_read_stack)
 			return 0;
@@ -525,11 +545,17 @@ pop_read_stack(void)
 	return read_state;
 }
 
+#ifdef AO_SCHEME_FEATURE_VECTOR
+#define is_open(t) ((t) == OPEN || (t) == OPEN_VECTOR)
+#else
+#define is_open(t) ((t) == OPEN)
+#endif
+
 ao_poly
 ao_scheme_read(void)
 {
 	struct ao_scheme_atom	*atom;
-	char			*string;
+	struct ao_scheme_string	*string;
 	int			read_state;
 	ao_poly			v = AO_SCHEME_NIL;
 
@@ -538,9 +564,11 @@ ao_scheme_read(void)
 	ao_scheme_read_cons = ao_scheme_read_cons_tail = ao_scheme_read_stack = 0;
 	for (;;) {
 		parse_token = lex();
-		while (parse_token == OPEN || parse_token == OPEN_VECTOR) {
+		while (is_open(parse_token)) {
+#ifdef AO_SCHEME_FEATURE_VECTOR
 			if (parse_token == OPEN_VECTOR)
 				read_state |= READ_SAW_VECTOR;
+#endif
 			if (!push_read_stack(read_state))
 				return AO_SCHEME_NIL;
 			ao_scheme_read_list++;
@@ -565,9 +593,11 @@ ao_scheme_read(void)
 		case NUM:
 			v = ao_scheme_integer_poly(token_int);
 			break;
+#ifdef AO_SCHEME_FEATURE_FLOAT
 		case FLOAT:
 			v = ao_scheme_float_get(token_float);
 			break;
+#endif
 		case BOOL:
 			if (token_string[0] == 't')
 				v = _ao_scheme_bool_true;
@@ -575,16 +605,18 @@ ao_scheme_read(void)
 				v = _ao_scheme_bool_false;
 			break;
 		case STRING:
-			string = ao_scheme_string_copy(token_string);
+			string = ao_scheme_string_make(token_string);
 			if (string)
 				v = ao_scheme_string_poly(string);
 			else
 				v = AO_SCHEME_NIL;
 			break;
 		case QUOTE:
+#ifdef AO_SCHEME_FEATURE_QUASI
 		case QUASIQUOTE:
 		case UNQUOTE:
 		case UNQUOTE_SPLICING:
+#endif
 			if (!push_read_stack(read_state))
 				return AO_SCHEME_NIL;
 			ao_scheme_read_list++;
@@ -593,6 +625,7 @@ ao_scheme_read(void)
 			case QUOTE:
 				v = _ao_scheme_atom_quote;
 				break;
+#ifdef AO_SCHEME_FEATURE_QUASI
 			case QUASIQUOTE:
 				v = _ao_scheme_atom_quasiquote;
 				break;
@@ -602,6 +635,7 @@ ao_scheme_read(void)
 			case UNQUOTE_SPLICING:
 				v = _ao_scheme_atom_unquote2dsplicing;
 				break;
+#endif
 			}
 			break;
 		case CLOSE:
@@ -612,8 +646,10 @@ ao_scheme_read(void)
 			v = ao_scheme_cons_poly(ao_scheme_read_cons);
 			--ao_scheme_read_list;
 			read_state = pop_read_stack();
+#ifdef AO_SCHEME_FEATURE_VECTOR
 			if (read_state & READ_SAW_VECTOR)
 				v = ao_scheme_vector_poly(ao_scheme_list_to_vector(ao_scheme_poly_cons(v)));
+#endif
 			break;
 		case DOT:
 			if (!ao_scheme_read_list) {
diff --git a/src/scheme/ao_scheme_read.h b/src/scheme/ao_scheme_read.h
index e10a7d05..1aa11a3a 100644
--- a/src/scheme/ao_scheme_read.h
+++ b/src/scheme/ao_scheme_read.h
@@ -24,15 +24,21 @@
 # define OPEN  			2
 # define CLOSE			3
 # define QUOTE			4
+#ifdef AO_SCHEME_FEATURE_QUASI
 # define QUASIQUOTE		5
 # define UNQUOTE		6
 # define UNQUOTE_SPLICING	7
+#endif
 # define STRING			8
 # define NUM			9
+#ifdef AO_SCHEME_FEATURE_FLOAT
 # define FLOAT			10
+#endif
 # define DOT			11
 # define BOOL			12
+#ifdef AO_SCHEME_FEATURE_VECTOR
 # define OPEN_VECTOR		13
+#endif
 
 /*
  * character classes
@@ -40,11 +46,20 @@
 
 # define PRINTABLE	0x0001	/* \t \n ' ' - ~ */
 # define SPECIAL	0x0002	/* ( [ { ) ] } ' ` , */
+#ifdef AO_SCHEME_FEATURE_QUASI
+# define SPECIAL_QUASI	SPECIAL
+#else
+# define SPECIAL_QUASI	0
+#endif
 # define DOTC		0x0004	/* . */
 # define WHITE		0x0008	/* ' ' \t \n */
 # define DIGIT		0x0010	/* [0-9] */
 # define SIGN		0x0020	/* +- */
+#ifdef AO_SCHEME_FEATURE_FLOAT
 # define FLOATC		0x0040	/* . e E */
+#else
+# define FLOATC		0
+#endif
 # define ENDOFFILE	0x0080	/* end of file */
 # define COMMENT	0x0100	/* ; */
 # define IGNORE		0x0200	/* \0 - ' ' */
diff --git a/src/scheme/ao_scheme_rep.c b/src/scheme/ao_scheme_rep.c
index 5b94d940..b35ba5b8 100644
--- a/src/scheme/ao_scheme_rep.c
+++ b/src/scheme/ao_scheme_rep.c
@@ -30,7 +30,7 @@ ao_scheme_read_eval_print(void)
 				break;
 			ao_scheme_exception = 0;
 		} else {
-			ao_scheme_poly_write(out);
+			ao_scheme_poly_write(out, true);
 			putchar ('\n');
 		}
 	}
diff --git a/src/scheme/ao_scheme_save.c b/src/scheme/ao_scheme_save.c
index af9345b8..3a595d71 100644
--- a/src/scheme/ao_scheme_save.c
+++ b/src/scheme/ao_scheme_save.c
@@ -17,11 +17,15 @@
 ao_poly
 ao_scheme_do_save(struct ao_scheme_cons *cons)
 {
+#ifdef AO_SCHEME_SAVE
+	struct ao_scheme_os_save *os;
+#endif
+
 	if (!ao_scheme_check_argc(_ao_scheme_atom_save, cons, 0, 0))
 		return AO_SCHEME_NIL;
 
 #ifdef AO_SCHEME_SAVE
-	struct ao_scheme_os_save *os = (struct ao_scheme_os_save *) (void *) &ao_scheme_pool[AO_SCHEME_POOL];
+	os = (struct ao_scheme_os_save *) (void *) &ao_scheme_pool[AO_SCHEME_POOL];
 
 	ao_scheme_collect(AO_SCHEME_COLLECT_FULL);
 	os->atoms = ao_scheme_atom_poly(ao_scheme_atoms);
@@ -38,12 +42,15 @@ ao_scheme_do_save(struct ao_scheme_cons *cons)
 ao_poly
 ao_scheme_do_restore(struct ao_scheme_cons *cons)
 {
+#ifdef AO_SCHEME_SAVE
+	struct ao_scheme_os_save save;
+	struct ao_scheme_os_save *os = (struct ao_scheme_os_save *) (void *) &ao_scheme_pool[AO_SCHEME_POOL];
+#endif
 	if (!ao_scheme_check_argc(_ao_scheme_atom_save, cons, 0, 0))
 		return AO_SCHEME_NIL;
 
 #ifdef AO_SCHEME_SAVE
-	struct ao_scheme_os_save save;
-	struct ao_scheme_os_save *os = (struct ao_scheme_os_save *) (void *) &ao_scheme_pool[AO_SCHEME_POOL];
+	os = (struct ao_scheme_os_save *) (void *) &ao_scheme_pool[AO_SCHEME_POOL];
 
 	if (!ao_scheme_os_restore_save(&save, AO_SCHEME_POOL))
 		return ao_scheme_error(AO_SCHEME_INVALID, "header restore failed");
diff --git a/src/scheme/ao_scheme_stack.c b/src/scheme/ao_scheme_stack.c
index d19dd6d6..863df3ca 100644
--- a/src/scheme/ao_scheme_stack.c
+++ b/src/scheme/ao_scheme_stack.c
@@ -158,26 +158,35 @@ ao_scheme_stack_clear(void)
 }
 
 void
-ao_scheme_stack_write(ao_poly poly)
+ao_scheme_stack_write(ao_poly poly, bool write)
 {
-	struct ao_scheme_stack *s = ao_scheme_poly_stack(poly);
+	struct ao_scheme_stack 	*s = ao_scheme_poly_stack(poly);
+	struct ao_scheme_stack	*clear = s;
+	int			written = 0;
 
+	(void) write;
+	ao_scheme_print_start();
+	ao_scheme_frame_print_indent += 2;
 	while (s) {
-		if (s->type & AO_SCHEME_STACK_PRINT) {
+		if (ao_scheme_print_mark_addr(s)) {
 			printf("[recurse...]");
-			return;
+			break;
 		}
-		s->type |= AO_SCHEME_STACK_PRINT;
+		written++;
 		printf("\t[\n");
-		printf("\t\texpr:   "); ao_scheme_poly_write(s->list); printf("\n");
-		printf("\t\tstate:  %s\n", ao_scheme_state_names[s->state]);
-		ao_scheme_error_poly ("values: ", s->values, s->values_tail);
-		ao_scheme_error_poly ("sexprs: ", s->sexprs, AO_SCHEME_NIL);
-		ao_scheme_error_frame(2, "frame:  ", ao_scheme_poly_frame(s->frame));
+		ao_scheme_printf("\t\texpr:     %v\n", s->list);
+		ao_scheme_printf("\t\tvalues:   %v\n", s->values);
+		ao_scheme_printf("\t\tframe:    %v\n", s->frame);
 		printf("\t]\n");
-		s->type &= ~AO_SCHEME_STACK_PRINT;
 		s = ao_scheme_poly_stack(s->prev);
 	}
+	ao_scheme_frame_print_indent -= 2;
+	if (ao_scheme_print_stop()) {
+		while (written--) {
+			ao_scheme_print_clear_addr(clear);
+			clear = ao_scheme_poly_stack(clear->prev);
+		}
+	}
 }
 
 /*
@@ -190,13 +199,13 @@ ao_scheme_stack_copy(struct ao_scheme_stack *old)
 	struct ao_scheme_stack *n, *prev = NULL;
 
 	while (old) {
-		ao_scheme_stack_stash(0, old);
-		ao_scheme_stack_stash(1, new);
-		ao_scheme_stack_stash(2, prev);
+		ao_scheme_stack_stash(old);
+		ao_scheme_stack_stash(new);
+		ao_scheme_stack_stash(prev);
 		n = ao_scheme_stack_new();
-		prev = ao_scheme_stack_fetch(2);
-		new = ao_scheme_stack_fetch(1);
-		old = ao_scheme_stack_fetch(0);
+		prev = ao_scheme_stack_fetch();
+		new = ao_scheme_stack_fetch();
+		old = ao_scheme_stack_fetch();
 		if (!n)
 			return NULL;
 
@@ -221,11 +230,12 @@ ao_scheme_stack_copy(struct ao_scheme_stack *old)
 ao_poly
 ao_scheme_stack_eval(void)
 {
+	struct ao_scheme_cons	*cons;
 	struct ao_scheme_stack	*new = ao_scheme_stack_copy(ao_scheme_poly_stack(ao_scheme_v));
 	if (!new)
 		return AO_SCHEME_NIL;
 
-	struct ao_scheme_cons	*cons = ao_scheme_poly_cons(ao_scheme_stack->values);
+	cons = ao_scheme_poly_cons(ao_scheme_stack->values);
 
 	if (!cons || !cons->cdr)
 		return ao_scheme_error(AO_SCHEME_INVALID, "continuation requires a value");
diff --git a/src/scheme/ao_scheme_string.c b/src/scheme/ao_scheme_string.c
index e25306cb..dfc74966 100644
--- a/src/scheme/ao_scheme_string.c
+++ b/src/scheme/ao_scheme_string.c
@@ -24,9 +24,10 @@ static void string_mark(void *addr)
 
 static int string_size(void *addr)
 {
+	struct ao_scheme_string	*string = addr;
 	if (!addr)
 		return 0;
-	return strlen(addr) + 1;
+	return strlen(string->val) + 2;
 }
 
 static void string_move(void *addr)
@@ -41,72 +42,122 @@ const struct ao_scheme_type ao_scheme_string_type = {
 	.name = "string",
 };
 
-char *
-ao_scheme_string_copy(char *a)
+static struct ao_scheme_string *
+ao_scheme_string_alloc(int len)
 {
-	int	alen = strlen(a);
+	struct ao_scheme_string	*s;
 
-	ao_scheme_string_stash(0, a);
-	char	*r = ao_scheme_alloc(alen + 1);
-	a = ao_scheme_string_fetch(0);
+	s = ao_scheme_alloc(len + 2);
+	if (!s)
+		return NULL;
+	s->type = AO_SCHEME_STRING;
+	return s;
+}
+
+struct ao_scheme_string *
+ao_scheme_string_copy(struct ao_scheme_string *a)
+{
+	int			alen = strlen(a->val);
+	struct ao_scheme_string	*r;
+
+	ao_scheme_string_stash(a);
+	r = ao_scheme_string_alloc(alen);
+	a = ao_scheme_string_fetch();
 	if (!r)
 		return NULL;
-	strcpy(r, a);
+	strcpy(r->val, a->val);
 	return r;
 }
 
-char *
-ao_scheme_string_cat(char *a, char *b)
+struct ao_scheme_string *
+ao_scheme_string_make(char *a)
 {
-	int	alen = strlen(a);
-	int	blen = strlen(b);
-
-	ao_scheme_string_stash(0, a);
-	ao_scheme_string_stash(1, b);
-	char	*r = ao_scheme_alloc(alen + blen + 1);
-	a = ao_scheme_string_fetch(0);
-	b = ao_scheme_string_fetch(1);
+	struct ao_scheme_string	*r;
+
+	r = ao_scheme_string_alloc(strlen(a));
 	if (!r)
 		return NULL;
-	strcpy(r, a);
-	strcpy(r+alen, b);
+	strcpy(r->val, a);
+	return r;
+}
+
+struct ao_scheme_string *
+ao_scheme_atom_to_string(struct ao_scheme_atom *a)
+{
+	int			alen = strlen(a->name);
+	struct ao_scheme_string	*r;
+
+	ao_scheme_atom_stash(a);
+	r = ao_scheme_string_alloc(alen);
+	a = ao_scheme_atom_fetch();
+	if (!r)
+		return NULL;
+	strcpy(r->val, a->name);
+	return r;
+}
+
+struct ao_scheme_string *
+ao_scheme_string_cat(struct ao_scheme_string *a, struct ao_scheme_string *b)
+{
+	int				alen = strlen(a->val);
+	int				blen = strlen(b->val);
+	struct ao_scheme_string 	*r;
+
+	ao_scheme_string_stash(a);
+	ao_scheme_string_stash(b);
+	r = ao_scheme_string_alloc(alen + blen);
+	b = ao_scheme_string_fetch();
+	a = ao_scheme_string_fetch();
+	if (!r)
+		return NULL;
+	strcpy(r->val, a->val);
+	strcpy(r->val+alen, b->val);
 	return r;
 }
 
 ao_poly
 ao_scheme_string_pack(struct ao_scheme_cons *cons)
 {
-	int	len = ao_scheme_cons_length(cons);
-	ao_scheme_cons_stash(0, cons);
-	char	*r = ao_scheme_alloc(len + 1);
-	cons = ao_scheme_cons_fetch(0);
-	char	*s = r;
+	struct ao_scheme_string	*r;
+	char			*rval;
+	int			len;
+
+	len = ao_scheme_cons_length(cons);
+	ao_scheme_cons_stash(cons);
+	r = ao_scheme_string_alloc(len);
+	cons = ao_scheme_cons_fetch();
+	if (!r)
+		return AO_SCHEME_NIL;
+	rval = r->val;
 
 	while (cons) {
-		if (!ao_scheme_integer_typep(ao_scheme_poly_type(cons->car)))
+		bool fail = false;
+		ao_poly	car = cons->car;
+		*rval++ = ao_scheme_poly_integer(car, &fail);
+		if (fail)
 			return ao_scheme_error(AO_SCHEME_INVALID, "non-int passed to pack");
-		*s++ = ao_scheme_poly_integer(cons->car);
-		cons = ao_scheme_poly_cons(cons->cdr);
+		cons = ao_scheme_cons_cdr(cons);
 	}
-	*s++ = 0;
+	*rval++ = 0;
 	return ao_scheme_string_poly(r);
 }
 
 ao_poly
-ao_scheme_string_unpack(char *a)
+ao_scheme_string_unpack(struct ao_scheme_string *a)
 {
 	struct ao_scheme_cons	*cons = NULL, *tail = NULL;
 	int			c;
 	int			i;
 
-	for (i = 0; (c = a[i]); i++) {
-		ao_scheme_cons_stash(0, cons);
-		ao_scheme_cons_stash(1, tail);
-		ao_scheme_string_stash(0, a);
-		struct ao_scheme_cons	*n = ao_scheme_cons_cons(ao_scheme_int_poly(c), AO_SCHEME_NIL);
-		a = ao_scheme_string_fetch(0);
-		cons = ao_scheme_cons_fetch(0);
-		tail = ao_scheme_cons_fetch(1);
+	for (i = 0; (c = a->val[i]); i++) {
+		struct ao_scheme_cons	*n;
+		ao_scheme_cons_stash(cons);
+		ao_scheme_cons_stash(tail);
+		ao_scheme_string_stash(a);
+		n = ao_scheme_cons_cons(ao_scheme_int_poly(c), AO_SCHEME_NIL);
+		a = ao_scheme_string_fetch();
+		tail = ao_scheme_cons_fetch();
+		cons = ao_scheme_cons_fetch();
 
 		if (!n) {
 			cons = NULL;
@@ -122,40 +173,36 @@ ao_scheme_string_unpack(char *a)
 }
 
 void
-ao_scheme_string_write(ao_poly p)
+ao_scheme_string_write(ao_poly p, bool write)
 {
-	char	*s = ao_scheme_poly_string(p);
-	char	c;
-
-	putchar('"');
-	while ((c = *s++)) {
-		switch (c) {
-		case '\n':
-			printf ("\\n");
-			break;
-		case '\r':
-			printf ("\\r");
-			break;
-		case '\t':
-			printf ("\\t");
-			break;
-		default:
-			if (c < ' ')
-				printf("\\%03o", c);
-			else
-				putchar(c);
-			break;
+	struct ao_scheme_string	*s = ao_scheme_poly_string(p);
+	char			*sval = s->val;
+	char			c;
+
+	if (write) {
+		putchar('"');
+		while ((c = *sval++)) {
+			switch (c) {
+			case '\n':
+				printf ("\\n");
+				break;
+			case '\r':
+				printf ("\\r");
+				break;
+			case '\t':
+				printf ("\\t");
+				break;
+			default:
+				if (c < ' ')
+					printf("\\%03o", c);
+				else
+					putchar(c);
+				break;
+			}
 		}
+		putchar('"');
+	} else {
+		while ((c = *sval++))
+			putchar(c);
 	}
-	putchar('"');
-}
-
-void
-ao_scheme_string_display(ao_poly p)
-{
-	char	*s = ao_scheme_poly_string(p);
-	char	c;
-
-	while ((c = *s++))
-		putchar(c);
 }
diff --git a/src/scheme/ao_scheme_vector.c b/src/scheme/ao_scheme_vector.c
new file mode 100644
index 00000000..afdc89a8
--- /dev/null
+++ b/src/scheme/ao_scheme_vector.c
@@ -0,0 +1,178 @@
+/*
+ * Copyright © 2017 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#include "ao_scheme.h"
+
+#ifdef AO_SCHEME_FEATURE_VECTOR
+
+static void vector_mark(void *addr)
+{
+	struct ao_scheme_vector	*vector = addr;
+	unsigned int	i;
+
+	for (i = 0; i < vector->length; i++) {
+		ao_poly v = vector->vals[i];
+
+		ao_scheme_poly_mark(v, 1);
+	}
+}
+
+static int vector_len_size(uint16_t length)
+{
+	return sizeof (struct ao_scheme_vector) + length * sizeof (ao_poly);
+}
+
+static int vector_size(void *addr)
+{
+	struct ao_scheme_vector *vector = addr;
+
+	return vector_len_size(vector->length);
+}
+
+static void vector_move(void *addr)
+{
+	struct ao_scheme_vector	*vector = addr;
+	unsigned int	i;
+
+	for (i = 0; i < vector->length; i++)
+		(void) ao_scheme_poly_move(&vector->vals[i], 1);
+}
+
+const struct ao_scheme_type ao_scheme_vector_type = {
+	.mark = vector_mark,
+	.size = vector_size,
+	.move = vector_move,
+	.name = "vector",
+};
+
+struct ao_scheme_vector *
+ao_scheme_vector_alloc(uint16_t length, ao_poly fill)
+{
+	struct ao_scheme_vector	*vector;
+	unsigned int i;
+
+	vector = ao_scheme_alloc(vector_len_size(length));
+	if (!vector)
+		return NULL;
+	vector->type = AO_SCHEME_VECTOR;
+	vector->length = length;
+	for (i = 0; i < length; i++)
+		vector->vals[i] = fill;
+	return vector;
+}
+
+void
+ao_scheme_vector_write(ao_poly v, bool write)
+{
+	struct ao_scheme_vector	*vector = ao_scheme_poly_vector(v);
+	unsigned int i;
+	int was_marked = 0;
+
+	ao_scheme_print_start();
+	was_marked = ao_scheme_print_mark_addr(vector);
+	if (was_marked) {
+		printf ("...");
+	} else {
+		printf("#(");
+		for (i = 0; i < vector->length; i++) {
+			if (i != 0)
+				printf(" ");
+			ao_scheme_poly_write(vector->vals[i], write);
+		}
+		printf(")");
+	}
+	if (ao_scheme_print_stop() && !was_marked)
+		ao_scheme_print_clear_addr(vector);
+}
+
+static int32_t
+ao_scheme_vector_offset(struct ao_scheme_vector *vector, ao_poly i)
+{
+	bool	fail;
+	int32_t	offset = ao_scheme_poly_integer(i, &fail);
+
+	if (fail)
+		ao_scheme_error(AO_SCHEME_INVALID, "vector index %v not integer", i);
+	if (offset < 0 || vector->length <= offset) {
+		ao_scheme_error(AO_SCHEME_INVALID, "vector index %v out of range (max %d)",
+				i, vector->length);
+		offset = -1;
+	}
+	return offset;
+}
+
+ao_poly
+ao_scheme_vector_get(ao_poly v, ao_poly i)
+{
+	struct ao_scheme_vector	*vector = ao_scheme_poly_vector(v);
+	int32_t			offset = ao_scheme_vector_offset(vector, i);
+
+	if (offset < 0)
+		return AO_SCHEME_NIL;
+	return vector->vals[offset];
+}
+
+ao_poly
+ao_scheme_vector_set(ao_poly v, ao_poly i, ao_poly p)
+{
+	struct ao_scheme_vector	*vector = ao_scheme_poly_vector(v);
+	int32_t			offset = ao_scheme_vector_offset(vector, i);
+
+	if (offset < 0)
+		return AO_SCHEME_NIL;
+	return vector->vals[offset] = p;
+}
+
+struct ao_scheme_vector *
+ao_scheme_list_to_vector(struct ao_scheme_cons *cons)
+{
+	uint16_t		length;
+	uint16_t		i;
+	struct ao_scheme_vector	*vector;
+
+	length = (uint16_t) ao_scheme_cons_length (cons);
+	if (ao_scheme_exception)
+		return NULL;
+
+	ao_scheme_cons_stash(cons);
+	vector = ao_scheme_vector_alloc(length, AO_SCHEME_NIL);
+	cons = ao_scheme_cons_fetch();
+	if (!vector)
+		return NULL;
+	i = 0;
+	while (cons) {
+		vector->vals[i++] = cons->car;
+		cons = ao_scheme_cons_cdr(cons);
+	}
+	return vector;
+}
+
+struct ao_scheme_cons *
+ao_scheme_vector_to_list(struct ao_scheme_vector *vector)
+{
+	unsigned int		i;
+	uint16_t		length = vector->length;
+	struct ao_scheme_cons	*cons = NULL;
+
+	for (i = length; i-- > 0;) {
+		ao_scheme_vector_stash(vector);
+		cons = ao_scheme_cons_cons(vector->vals[i], ao_scheme_cons_poly(cons));
+		vector = ao_scheme_vector_fetch();
+		if (!cons)
+			return NULL;
+	}
+	return cons;
+}
+
+#endif /* AO_SCHEME_FEATURE_VECTOR */
diff --git a/src/scheme/make-const/Makefile b/src/scheme/make-const/Makefile
index caf7acbe..a8e3a7f5 100644
--- a/src/scheme/make-const/Makefile
+++ b/src/scheme/make-const/Makefile
@@ -10,7 +10,7 @@ HDRS=$(SCHEME_HDRS) ao_scheme_os.h
 OBJS=$(SRCS:.c=.o)
 
 CC=cc
-CFLAGS=-DAO_SCHEME_MAKE_CONST -O0 -g -I. -Wall -Wextra
+CFLAGS=-DAO_SCHEME_MAKE_CONST -O0 -g -I. -Wall -Wextra -Wpointer-arith -Wmissing-declarations -Wformat=2 -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Wbad-function-cast -Wold-style-definition -Wdeclaration-after-statement -Wunused -Wuninitialized -Wshadow -Wmissing-noreturn -Wmissing-format-attribute -Wredundant-decls -Wlogical-op -Werror=implicit -Werror=nonnull -Werror=init-self -Werror=main -Werror=missing-braces -Werror=sequence-point -Werror=return-type -Werror=trigraphs -Werror=array-bounds -Werror=write-strings -Werror=address -Werror=int-to-pointer-cast -Werror=pointer-to-int-cast
 
 .c.o:
 	$(CC) -c $(CFLAGS) $< -o $@
diff --git a/src/scheme/test/.gitignore b/src/scheme/test/.gitignore
index 3cdae594..3622bc1d 100644
--- a/src/scheme/test/.gitignore
+++ b/src/scheme/test/.gitignore
@@ -1 +1 @@
-ao_scheme_test
+ao-scheme
diff --git a/src/scheme/test/Makefile b/src/scheme/test/Makefile
index c48add1f..ee46118e 100644
--- a/src/scheme/test/Makefile
+++ b/src/scheme/test/Makefile
@@ -5,18 +5,26 @@ vpath %.c ..
 vpath %.h ..
 
 SRCS=$(SCHEME_SRCS) ao_scheme_test.c
+HDRS=$(SCHEME_HDRS) ao_scheme_const.h
 
 OBJS=$(SRCS:.c=.o)
 
-CFLAGS=-O2 -g -Wall -Wextra -I. -I..
+#PGFLAGS=-pg -no-pie
+OFLAGS=-O3
+#DFLAGS=-O0
 
-ao_scheme_test: $(OBJS)
+CFLAGS=$(DFLAGS) $(OFLAGS) $(PGFLAGS) -g -Wall -Wextra -I. -I.. -Wpointer-arith -Wmissing-declarations -Wformat=2 -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Wbad-function-cast -Wold-style-definition -Wdeclaration-after-statement -Wunused -Wuninitialized -Wshadow -Wmissing-noreturn -Wmissing-format-attribute -Wredundant-decls -Wlogical-op -Werror=implicit -Werror=nonnull -Werror=init-self -Werror=main -Werror=missing-braces -Werror=sequence-point -Werror=return-type -Werror=trigraphs -Werror=array-bounds -Werror=write-strings -Werror=address -Werror=int-to-pointer-cast -Werror=pointer-to-int-cast
+
+ao-scheme: $(OBJS)
 	cc $(CFLAGS) -o $@ $(OBJS) -lm
 
-$(OBJS): $(SCHEME_HDRS)
+$(OBJS): $(HDRS)
+
+ao_scheme_const.h: ../make-const/ao_scheme_make_const ../ao_scheme_const.scheme
+	../make-const/ao_scheme_make_const -o $@ ../ao_scheme_const.scheme
 
 clean::
-	rm -f $(OBJS) ao_scheme_test
+	rm -f $(OBJS) ao-scheme ao_scheme_const.h
 
-install: ao_scheme_test
-	cp ao_scheme_test $$HOME/bin/ao-scheme
+install: ao-scheme
+	install -t $$HOME/bin $^
diff --git a/src/scheme/test/ao_scheme_os.h b/src/scheme/test/ao_scheme_os.h
index ea363fb3..b225b2e8 100644
--- a/src/scheme/test/ao_scheme_os.h
+++ b/src/scheme/test/ao_scheme_os.h
@@ -24,12 +24,11 @@
 
 #define AO_SCHEME_POOL_TOTAL	32768
 #define AO_SCHEME_SAVE		1
-#define DBG_MEM_STATS		1
 
 extern int ao_scheme_getc(void);
 
 static inline void
-ao_scheme_os_flush() {
+ao_scheme_os_flush(void) {
 	fflush(stdout);
 }
 
diff --git a/src/scheme/test/ao_scheme_test.c b/src/scheme/test/ao_scheme_test.c
index 0c77d8d5..45068369 100644
--- a/src/scheme/test/ao_scheme_test.c
+++ b/src/scheme/test/ao_scheme_test.c
@@ -107,6 +107,7 @@ main (int argc, char **argv)
 	}
 	ao_scheme_read_eval_print();
 
+#ifdef DBG_MEM_STATS
 	printf ("collects: full: %lu incremental %lu\n",
 		ao_scheme_collects[AO_SCHEME_COLLECT_FULL],
 		ao_scheme_collects[AO_SCHEME_COLLECT_INCREMENTAL]);
@@ -136,4 +137,5 @@ main (int argc, char **argv)
 	       (double) ao_scheme_loops[AO_SCHEME_COLLECT_FULL],
 	       (double) ao_scheme_freed[AO_SCHEME_COLLECT_INCREMENTAL] /
 	       (double) ao_scheme_loops[AO_SCHEME_COLLECT_INCREMENTAL]);
+#endif
 }
diff --git a/src/scheme/tiny-test/.gitignore b/src/scheme/tiny-test/.gitignore
new file mode 100644
index 00000000..7c4c3956
--- /dev/null
+++ b/src/scheme/tiny-test/.gitignore
@@ -0,0 +1 @@
+ao-scheme-tiny
diff --git a/src/scheme/tiny-test/Makefile b/src/scheme/tiny-test/Makefile
new file mode 100644
index 00000000..6b1fe003
--- /dev/null
+++ b/src/scheme/tiny-test/Makefile
@@ -0,0 +1,28 @@
+include ../Makefile-inc
+
+vpath %.o .
+vpath %.c ..
+vpath %.h ..
+
+DEFS=
+
+SRCS=$(SCHEME_SRCS) ao_scheme_test.c
+HDRS=$(SCHEME_HDRS) ao_scheme_const.h
+
+OBJS=$(SRCS:.c=.o)
+
+CFLAGS=-O0 -g -Wall -Wextra -I. -I.. -Wpointer-arith -Wmissing-declarations -Wformat=2 -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Wbad-function-cast -Wold-style-definition -Wdeclaration-after-statement -Wunused -Wuninitialized -Wshadow -Wmissing-noreturn -Wmissing-format-attribute -Wredundant-decls -Wlogical-op -Werror=implicit -Werror=nonnull -Werror=init-self -Werror=main -Werror=missing-braces -Werror=sequence-point -Werror=return-type -Werror=trigraphs -Werror=array-bounds -Werror=write-strings -Werror=address -Werror=int-to-pointer-cast -Werror=pointer-to-int-cast
+
+ao-scheme-tiny: $(OBJS)
+	cc $(CFLAGS) -o $@ $(OBJS) -lm
+
+$(OBJS): $(HDRS)
+
+ao_scheme_const.h: ../make-const/ao_scheme_make_const ao_scheme_tiny_const.scheme
+	../make-const/ao_scheme_make_const -o $@ -d FLOAT,VECTOR,QUASI,BIGINT ao_scheme_tiny_const.scheme
+
+clean::
+	rm -f $(OBJS) ao-scheme-tiny ao_scheme_const.h
+
+install: ao-scheme-tiny
+	cp $^ $$HOME/bin
diff --git a/src/scheme/tiny-test/ao_scheme_os.h b/src/scheme/tiny-test/ao_scheme_os.h
new file mode 100644
index 00000000..b9f3e31f
--- /dev/null
+++ b/src/scheme/tiny-test/ao_scheme_os.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright © 2016 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#ifndef _AO_SCHEME_OS_H_
+#define _AO_SCHEME_OS_H_
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+
+#define AO_SCHEME_POOL_TOTAL	4096
+#define AO_SCHEME_SAVE		1
+
+extern int ao_scheme_getc(void);
+
+static inline void
+ao_scheme_os_flush(void) {
+	fflush(stdout);
+}
+
+static inline void
+ao_scheme_abort(void)
+{
+	abort();
+}
+
+static inline void
+ao_scheme_os_led(int led)
+{
+	printf("leds set to 0x%x\n", led);
+}
+
+#define AO_SCHEME_JIFFIES_PER_SECOND	100
+
+static inline void
+ao_scheme_os_delay(int jiffies)
+{
+	struct timespec ts = {
+		.tv_sec = jiffies / AO_SCHEME_JIFFIES_PER_SECOND,
+		.tv_nsec = (jiffies % AO_SCHEME_JIFFIES_PER_SECOND) * (1000000000L / AO_SCHEME_JIFFIES_PER_SECOND)
+	};
+	nanosleep(&ts, NULL);
+}
+
+static inline int
+ao_scheme_os_jiffy(void)
+{
+	struct timespec tp;
+	clock_gettime(CLOCK_MONOTONIC, &tp);
+	return tp.tv_sec * AO_SCHEME_JIFFIES_PER_SECOND + (tp.tv_nsec / (1000000000L / AO_SCHEME_JIFFIES_PER_SECOND));
+}
+
+#endif
diff --git a/src/scheme/tiny-test/ao_scheme_test.c b/src/scheme/tiny-test/ao_scheme_test.c
new file mode 100644
index 00000000..45068369
--- /dev/null
+++ b/src/scheme/tiny-test/ao_scheme_test.c
@@ -0,0 +1,141 @@
+/*
+ * Copyright © 2016 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#include "ao_scheme.h"
+#include <stdio.h>
+
+static FILE *ao_scheme_file;
+static int newline = 1;
+
+static char save_file[] = "scheme.image";
+
+int
+ao_scheme_os_save(void)
+{
+	FILE	*save = fopen(save_file, "w");
+
+	if (!save) {
+		perror(save_file);
+		return 0;
+	}
+	fwrite(ao_scheme_pool, 1, AO_SCHEME_POOL_TOTAL, save);
+	fclose(save);
+	return 1;
+}
+
+int
+ao_scheme_os_restore_save(struct ao_scheme_os_save *save, int offset)
+{
+	FILE	*restore = fopen(save_file, "r");
+	size_t	ret;
+
+	if (!restore) {
+		perror(save_file);
+		return 0;
+	}
+	fseek(restore, offset, SEEK_SET);
+	ret = fread(save, sizeof (struct ao_scheme_os_save), 1, restore);
+	fclose(restore);
+	if (ret != 1)
+		return 0;
+	return 1;
+}
+
+int
+ao_scheme_os_restore(void)
+{
+	FILE	*restore = fopen(save_file, "r");
+	size_t	ret;
+
+	if (!restore) {
+		perror(save_file);
+		return 0;
+	}
+	ret = fread(ao_scheme_pool, 1, AO_SCHEME_POOL_TOTAL, restore);
+	fclose(restore);
+	if (ret != AO_SCHEME_POOL_TOTAL)
+		return 0;
+	return 1;
+}
+
+int
+ao_scheme_getc(void)
+{
+	int c;
+
+	if (ao_scheme_file)
+		return getc(ao_scheme_file);
+
+	if (newline) {
+		if (ao_scheme_read_list)
+			printf("+ ");
+		else
+			printf("> ");
+		newline = 0;
+	}
+	c = getchar();
+	if (c == '\n')
+		newline = 1;
+	return c;
+}
+
+int
+main (int argc, char **argv)
+{
+	(void) argc;
+
+	while (*++argv) {
+		ao_scheme_file = fopen(*argv, "r");
+		if (!ao_scheme_file) {
+			perror(*argv);
+			exit(1);
+		}
+		ao_scheme_read_eval_print();
+		fclose(ao_scheme_file);
+		ao_scheme_file = NULL;
+	}
+	ao_scheme_read_eval_print();
+
+#ifdef DBG_MEM_STATS
+	printf ("collects: full: %lu incremental %lu\n",
+		ao_scheme_collects[AO_SCHEME_COLLECT_FULL],
+		ao_scheme_collects[AO_SCHEME_COLLECT_INCREMENTAL]);
+
+	printf ("freed: full %lu incremental %lu\n",
+		ao_scheme_freed[AO_SCHEME_COLLECT_FULL],
+		ao_scheme_freed[AO_SCHEME_COLLECT_INCREMENTAL]);
+
+	printf("loops: full %lu incremental %lu\n",
+		ao_scheme_loops[AO_SCHEME_COLLECT_FULL],
+		ao_scheme_loops[AO_SCHEME_COLLECT_INCREMENTAL]);
+
+	printf("loops per collect: full %f incremental %f\n",
+	       (double) ao_scheme_loops[AO_SCHEME_COLLECT_FULL] /
+	       (double) ao_scheme_collects[AO_SCHEME_COLLECT_FULL],
+	       (double) ao_scheme_loops[AO_SCHEME_COLLECT_INCREMENTAL] /
+	       (double) ao_scheme_collects[AO_SCHEME_COLLECT_INCREMENTAL]);
+
+	printf("freed per collect: full %f incremental %f\n",
+	       (double) ao_scheme_freed[AO_SCHEME_COLLECT_FULL] /
+	       (double) ao_scheme_collects[AO_SCHEME_COLLECT_FULL],
+	       (double) ao_scheme_freed[AO_SCHEME_COLLECT_INCREMENTAL] /
+	       (double) ao_scheme_collects[AO_SCHEME_COLLECT_INCREMENTAL]);
+
+	printf("freed per loop: full %f incremental %f\n",
+	       (double) ao_scheme_freed[AO_SCHEME_COLLECT_FULL] /
+	       (double) ao_scheme_loops[AO_SCHEME_COLLECT_FULL],
+	       (double) ao_scheme_freed[AO_SCHEME_COLLECT_INCREMENTAL] /
+	       (double) ao_scheme_loops[AO_SCHEME_COLLECT_INCREMENTAL]);
+#endif
+}
diff --git a/src/scheme/tiny-test/ao_scheme_tiny_const.scheme b/src/scheme/tiny-test/ao_scheme_tiny_const.scheme
new file mode 100644
index 00000000..d0c0e578
--- /dev/null
+++ b/src/scheme/tiny-test/ao_scheme_tiny_const.scheme
@@ -0,0 +1,389 @@
+;
+; Copyright © 2016 Keith Packard <keithp@keithp.com>
+;
+; This program is free software; you can redistribute it and/or modify
+; it under the terms of the GNU General Public License as published by
+; the Free Software Foundation, either version 2 of the License, or
+; (at your option) any later version.
+;
+; This program is distributed in the hope that it will be useful, but
+; WITHOUT ANY WARRANTY; without even the implied warranty of
+; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+; General Public License for more details.
+;
+; Lisp code placed in ROM
+
+					; return a list containing all of the arguments
+(def (quote list) (lambda l l))
+
+(def (quote def!)
+     (macro (a b)
+	    (list
+	     def
+	     (list quote a)
+	     b)
+	    )
+     )
+
+(begin
+ (def! append
+   (lambda args
+	  (def! a-l
+	    (lambda (a b)
+	      (cond ((null? a) b)
+		    (else (cons (car a) (a-l (cdr a) b)))
+		    )
+	      )
+	    )
+	    
+	  (def! a-ls
+	    (lambda (l)
+	      (cond ((null? l) l)
+		    ((null? (cdr l)) (car l))
+		    (else (a-l (car l) (a-ls (cdr l))))
+		    )
+	      )
+	    )
+	  (a-ls args)
+	  )
+   )
+ 'append)
+
+(append '(a b c) '(d e f) '(g h i))
+
+					;
+					; Define a variable without returning the value
+					; Useful when defining functions to avoid
+					; having lots of output generated.
+					;
+					; Also accepts the alternate
+					; form for defining lambdas of
+					; (define (name a y z) sexprs ...) 
+					;
+
+(begin
+ (def (quote define)
+   (macro (a . b)
+					; check for alternate lambda definition form
+
+	  (cond ((list? a)
+		 (set! b
+		       (cons lambda (cons (cdr a) b)))
+		 (set! a (car a))
+		 )
+		(else
+		 (set! b (car b))
+		 )
+		)
+	  (cons begin
+		(cons
+		 (cons def
+		       (cons (cons quote (cons a '()))
+			     (cons b '())
+			     )
+		       )
+		 (cons
+		  (cons quote (cons a '()))
+		  '())
+		 )
+		)
+	  )
+   )
+ 'define
+ )
+
+					; basic list accessors
+
+(define (caar l) (car (car l)))
+
+(define (cadr l) (car (cdr l)))
+
+(define (cdar l) (cdr (car l)))
+
+(define (caddr l) (car (cdr (cdr l))))
+
+					; (if <condition> <if-true>)
+					; (if <condition> <if-true> <if-false)
+
+(define if
+  (macro (test . args)
+    (cond ((null? (cdr args))
+	   (list cond (list test (car args)))
+		)
+	  (else
+	   (list cond
+		 (list test (car args))
+		 (list 'else (cadr args))
+		 )
+	   )
+	  )
+    )
+  )
+
+(if (> 3 2) 'yes)
+(if (> 3 2) 'yes 'no)
+(if (> 2 3) 'no 'yes)
+(if (> 2 3) 'no)
+
+					; simple math operators
+
+(define zero? (macro (value) (list eqv? value 0)))
+
+(zero? 1)
+(zero? 0)
+(zero? "hello")
+
+(define positive? (macro (value) (list > value 0)))
+
+(positive? 12)
+(positive? -12)
+
+(define negative? (macro (value) (list < value 0)))
+
+(negative? 12)
+(negative? -12)
+
+(define (abs a) (if (>= a 0) a (- a)))
+
+(abs 12)
+(abs -12)
+
+(define max (lambda (a . b)
+		   (while (not (null? b))
+		     (cond ((< a (car b))
+			    (set! a (car b)))
+			   )
+		     (set! b (cdr b))
+		     )
+		   a)
+  )
+
+(max 1 2 3)
+(max 3 2 1)
+
+(define min (lambda (a . b)
+		   (while (not (null? b))
+		     (cond ((> a (car b))
+			    (set! a (car b)))
+			   )
+		     (set! b (cdr b))
+		     )
+		   a)
+  )
+
+(min 1 2 3)
+(min 3 2 1)
+
+(define (even? a) (zero? (% a 2)))
+
+(even? 2)
+(even? -2)
+(even? 3)
+(even? -1)
+
+(define (odd? a) (not (even? a)))
+
+(odd? 2)
+(odd? -2)
+(odd? 3)
+(odd? -1)
+
+
+(define (list-tail a b)
+  (if (zero? b)
+      a
+    (list-tail (cdr a (- b 1)))
+    )
+  )
+
+(define (list-ref a b)
+  (car (list-tail a b))
+  )
+
+(define (list-tail a b)
+  (if (zero? b)
+      a
+    (list-tail (cdr a) (- b 1))))
+
+(list-tail '(1 2 3) 2)
+
+(define (list-ref a b) (car (list-tail a b)))
+
+(list-ref '(1 2 3) 2)
+    
+
+					; define a set of local
+					; variables one at a time and
+					; then evaluate a list of
+					; sexprs
+					;
+					; (let* (var-defines) sexprs)
+					;
+					; where var-defines are either
+					;
+					; (name value)
+					;
+					; or
+					;
+					; (name)
+					;
+					; e.g.
+					;
+					; (let* ((x 1) (y)) (set! y (+ x 1)) y)
+
+(define let*
+  (macro (a . b)
+
+					;
+					; make the list of names in the let
+					;
+
+	 (define (_n a)
+	   (cond ((not (null? a))
+		  (cons (car (car a))
+			(_n (cdr a))))
+		 (else ())
+		 )
+	   )
+
+					; the set of expressions is
+					; the list of set expressions
+					; pre-pended to the
+					; expressions to evaluate
+
+	 (define (_v a b)
+	   (cond ((null? a) b)		 (else
+		  (cons
+		   (list set
+			 (list quote
+			       (car (car a))
+			       )
+			 (cond ((null? (cdr (car a))) ())
+			       (else (cadr (car a))))
+			 )
+		   (_v (cdr a) b)
+		   )
+		  )
+		 )
+	   )
+
+					; the parameters to the lambda is a list
+					; of nils of the right length
+
+	 (define (_z a)
+	   (cond ((null? a) ())
+		 (else (cons () (_z (cdr a))))
+		 )
+	   )
+					; build the lambda.
+
+	 (cons (cons lambda (cons (_n a) (_v a b))) (_z a))
+	 )
+     )
+
+(let* ((a 1) (y a)) (+ a y))
+
+(define let let*)
+					; recursive equality
+
+(define (equal? a b)
+  (cond ((eq? a b) #t)
+	((pair? a)
+	 (cond ((pair? b)
+		(cond ((equal? (car a) (car b))
+		       (equal? (cdr a) (cdr b)))
+		      )
+		)
+	       )
+	 )
+	)
+  )
+
+(equal? '(a b c) '(a b c))
+(equal? '(a b c) '(a b b))
+
+(define member (lambda (obj a . test?)
+		      (cond ((null? a)
+			     #f
+			     )
+			    (else
+			     (if (null? test?) (set! test? equal?) (set! test? (car test?)))
+			     (if (test? obj (car a))
+				 a
+			       (member obj (cdr a) test?))
+			     )
+			    )
+		      )
+  )
+
+(member '(2) '((1) (2) (3)))
+
+(member '(4) '((1) (2) (3)))
+
+(define (memq obj a) (member obj a eq?))
+
+(memq 2 '(1 2 3))
+
+(memq 4 '(1 2 3))
+
+(memq '(2) '((1) (2) (3)))
+
+(define (_assoc a b t?)
+  (if (null? b)
+      #f
+    (if (t? a (caar b))
+	(car b)
+      (_assoc a (cdr b) t?)
+      )
+    )
+  )
+
+(define (assq a b) (_assoc a b eq?))
+(define (assoc a b) (_assoc a b equal?))
+
+(assq 'a '((a 1) (b 2) (c 3)))
+(assoc '(c) '((a 1) (b 2) ((c) 3)))
+
+(define string (lambda a (list->string a)))
+
+(display "apply\n")
+(apply cons '(a b))
+
+(define map
+  (lambda (a . b)
+	 (define (args b)
+	   (cond ((null? b) ())
+		 (else
+		  (cons (caar b) (args (cdr b)))
+		  )
+		 )
+	   )
+	 (define (next b)
+	   (cond ((null? b) ())
+		 (else
+		  (cons (cdr (car b)) (next (cdr b)))
+		  )
+		 )
+	   )
+	 (define (domap b)
+	   (cond ((null? (car b)) ())
+		 (else
+		  (cons (apply a (args b)) (domap (next b)))
+		  )
+		 )
+	   )
+	 (domap b)
+	 )
+  )
+
+(map cadr '((a b) (d e) (g h)))
+
+(define for-each (lambda (a . b)
+			(apply map a b)
+			#t))
+
+(for-each display '("hello" " " "world" "\n"))
+
+(define (newline) (write-char #\newline))
+
+(newline)
diff --git a/src/stm/altos-loader.ld b/src/stm/altos-loader.ld
index a4a7dc43..806b4842 100644
--- a/src/stm/altos-loader.ld
+++ b/src/stm/altos-loader.ld
@@ -72,8 +72,9 @@ SECTIONS {
 	} >ram AT>rom
 
 	/* Data -- relocated to RAM, but written to ROM
+	 * Also aligned to 8 bytes to agree with textram
 	 */
-	.data : {
+	.data BLOCK(8): {
 		*(.data)	/* initialized data */
 		__data_end__ = .;
 	} >ram AT>rom
diff --git a/src/stmf0/altos-loader.ld b/src/stmf0/altos-loader.ld
index c458116b..05887d0e 100644
--- a/src/stmf0/altos-loader.ld
+++ b/src/stmf0/altos-loader.ld
@@ -72,9 +72,10 @@ SECTIONS {
 		__text_ram_end = .;
 	} >ram AT>rom
 
-	/* Data -- relocated to RAM, but written to ROM
+	/* Data -- relocated to RAM, but written to ROM.
+	 * also aligned to 8 bytes in case textram is empty
 	 */
-	.data : {
+	.data BLOCK(8): {
 		*(.data)	/* initialized data */
 		__data_end__ = .;
 	} >ram AT>rom