diff --git a/.gitignore b/.gitignore
index 96b7d40..557a1ea 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,4 @@
 *.lst
 *.sym
 mkfs
+2063-Z80-cpm.tar
diff --git a/Makefile b/Makefile
index d58afc5..9059c3a 100644
--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,7 @@ SUBDIRS=\
 CLEAN_DIRS=$(SUBDIRS:%=clean-%)
 ALL_DIRS=$(SUBDIRS:%=all-%)
 
-.PHONY: all clean $(CLEAN_DIRS) $(ALL_DIRS)
+.PHONY: all clean release $(CLEAN_DIRS) $(ALL_DIRS)
 
 all:: $(ALL_DIRS)
 
@@ -23,3 +23,30 @@ $(ALL_DIRS):
 $(CLEAN_DIRS):
 	$(MAKE) -C $(@:clean-%=%) clean
 
+
+REL_FILES=\
+	LICENSE \
+	Makefile \
+	README-SD.md \
+	README.md \
+	boot \
+	cpm22 \
+	doc \
+	hello \
+	lib \
+	retro \
+	tests \
+	filesystem/Makefile \
+	filesystem/README.md \
+	filesystem/diskdefs \
+    filesystem/retro.img \
+	filesystem/sid \
+	filesystem/progs/basic/ \
+    filesystem/progs/example \
+	filesystem/progs/tms9118 \
+	filesystem/progs/tty \
+	filesystem/progs/README.md
+
+release:
+	rm -f 2063-Z80-cpm.tar
+	zip -r 2063-Z80-cpm.tar $(REL_FILES)
diff --git a/doc/retro.pdf b/doc/retro.pdf
index 3e8bad4..5911385 100644
Binary files a/doc/retro.pdf and b/doc/retro.pdf differ
diff --git a/filesystem/Makefile b/filesystem/Makefile
index 85905d0..6ebf1d2 100644
--- a/filesystem/Makefile
+++ b/filesystem/Makefile
@@ -10,24 +10,40 @@
 # To list the files that are in the created image:
 # make lsimg
 
+SUBDIRS=\
+	progs/tty \
+	progs/example \
+	progs/tms9118
 
-all: retro.img
+CLEAN_DIRS=$(SUBDIRS:%=clean-%)
+ALL_DIRS=$(SUBDIRS:%=all-%)
 
-retro.img: ../retro/retro.bin ../cpm22/filesystem/* adventure/adv-B03
+.PHONY: all clean $(CLEAN_DIRS) $(ALL_DIRS)
+
+all:: $(ALL_DIRS)
+
+clean:: $(CLEAN_DIRS)
+
+world:: clean all
+
+$(ALL_DIRS):
+	$(MAKE) -C $(@:all-%=%) all
+
+$(CLEAN_DIRS):
+	$(MAKE) -C $(@:clean-%=%) clean
+
+
+
+
+all:: retro.img
+
+retro.img: ../retro/retro.bin 
 	rm -f retro.img
 	mkfs.cpm -f z80-retro-2k-8m -b ../retro/retro.bin retro.img
 	cpmcp -f z80-retro-2k-8m retro.img ../cpm22/filesystem/* 0:
+	cpmcp -f z80-retro-2k-8m retro.img assemblers/sid/*.com 0:
 	cpmcp -f z80-retro-2k-8m retro.img adventure/adv-B03/* 0:
-
-tms9118: retro.img
-	if [ `ls -1 progs/tms9118/*.com 2>/dev/null | wc -l` -gt 0 ]; then\
-		cpmcp -f z80-retro-2k-8m retro.img progs/tms9118/*.com 0: ; \
-	fi
-
-assemblers: retro.img
-	if [ `ls -1 assemblers/*/* 2>/dev/null | wc -l` -gt 0 ]; then\
-		cpmcp -f z80-retro-2k-8m retro.img assemblers/*/* 0: ; \
-	fi
+	cpmcp -f z80-retro-2k-8m retro.img progs/tms9118/*.com 0:
 
 local: retro.img
 	if [ `ls -1 local/*/*/* 2>/dev/null | wc -l` -gt 0 ]; then\
@@ -41,17 +57,13 @@ local: retro.img
 	fi
 
 
-world: clean all
-
-adventure/adv-B03: adventure/cpm-advent.zip
-	unzip -d adventure adventure/cpm-advent.zip
-
+# this is where the adventure game files came from:
 adventure/cpm-advent.zip:
 	wget -P adventure https://ifarchive.org/if-archive/games/cpm/cpm-advent.zip 
 
-clean:
+
+clean::
 	rm -f retro.img 
-	rm -rf `find adventure/* -name \*.zip -o -print`
 
 burn: retro.img
 	if [ `hostname` = "raspberrypi" ]; then \
diff --git a/filesystem/assemblers/sid/SID.COM b/filesystem/assemblers/sid/sid.com
similarity index 100%
rename from filesystem/assemblers/sid/SID.COM
rename to filesystem/assemblers/sid/sid.com
diff --git a/filesystem/assemblers/sid/ZSID.COM b/filesystem/assemblers/sid/zsid.com
similarity index 100%
rename from filesystem/assemblers/sid/ZSID.COM
rename to filesystem/assemblers/sid/zsid.com