diff --git a/build/Makefile b/build/Makefile
index 6573653..66c54da 100644
--- a/build/Makefile
+++ b/build/Makefile
@@ -95,8 +95,9 @@ dirs:
 cmd: dirs $(BINDIR)/as $(BINDIR)/cat $(BINDIR)/check $(BINDIR)/chmod \
 	$(BINDIR)/chown $(BINDIR)/chrm $(BINDIR)/cp $(BINDIR)/ds \
 	$(BINDIR)/dskres $(BINDIR)/dsksav $(BINDIR)/ed $(BINDIR)/init \
-	$(BINDIR)/db $(BINDIR)/stat $(BINDIR)/tm $(BINDIR)/dsw $(BINDIR)/apr 
-
+	$(BINDIR)/db $(BINDIR)/stat $(BINDIR)/tm $(BINDIR)/dsw $(BINDIR)/apr \
+	$(BINDIR)/cas
+	
 # Alternate commands: no dd, but . and ..
 altcmd: dirs $(BINDIR)/as $(BINDIR)/cat $(BINDIR)/check $(BINDIR)/chmod \
 	$(BINDIR)/chown $(BINDIR)/altchrm $(BINDIR)/cp $(BINDIR)/ds \
@@ -150,6 +151,9 @@ $(BINDIR)/stat: $(CMDSRC)/stat/stat.s
 $(BINDIR)/tm: $(CMDSRC)/tm/tm.s
 	$(AS) $(ASARGS) -o $(BINDIR)/tm $(CMDSRC)/tm/tm.s
 
+$(BINDIR)/cas: $(CMDSRC)/cas/cas.s
+	$(AS) $(ASARGS) -o $(BINDIR)/cas $(CMDSRC)/cas/cas.s
+
 # -- compile errors
 $(BINDIR)/dmabs: $(CMDSRC)/dmabs/dmabs.s
 	$(AS) $(ASARGS) -o $(BINDIR)/dmabs $(CMDSRC)/dmabs/dmabs.s
diff --git a/build/proto b/build/proto
index e09ea10..76319f0 100644
--- a/build/proto
+++ b/build/proto
@@ -23,6 +23,7 @@ dd 	         drwr- -1 4
         apr      frwr- -1 bin/apr
         as       frwr- -1 bin/as
         bc       frwr- -1 bin/bc
+        cas      frwr- -1 bin/cas
         cat      frwr- -1 bin/cat
         check    frwr- -1 bin/check
         chmod    frwr- -1 bin/chmod