diff --git a/emul/Makefile b/emul/Makefile
index 7c5f45a..c78c3c9 100644
--- a/emul/Makefile
+++ b/emul/Makefile
@@ -1,4 +1,4 @@
-TARGETS = forth stage
+TARGETS = forth stage blkfs
 OBJS = emul.o libz80/libz80.o
 BIN2C = ../tools/bin2c
 BLKPACK = ../tools/blkpack
@@ -18,17 +18,14 @@ $(BLKUNPACK): $(BLKPACK)
 forth-bin.h: $(BIN2C)
 	$(BIN2C) KERNEL < forth.bin > $@
 
-stage: stage.c $(OBJS) forth-bin.h blkfs-bin.h
-	$(CC) stage.c $(OBJS) -o $@
+stage: stage.c $(OBJS) forth-bin.h
+	$(CC) stage.c -DBLKFS_PATH=\"`pwd`/blkfs\" $(OBJS) -o $@
 
 blkfs: $(BLKPACK)
 	$(BLKPACK) ../blk > $@
 
-blkfs-bin.h: blkfs $(BIN2C)
-	$(BIN2C) BLKFS < blkfs > $@
-
-forth: forth.c $(OBJS) forth-bin.h blkfs-bin.h
-	$(CC) forth.c $(OBJS) -lncurses -o $@
+forth: forth.c $(OBJS) forth-bin.h
+	$(CC) forth.c -DBLKFS_PATH=\"`pwd`/blkfs\" $(OBJS) -lncurses -o $@
 
 libz80/libz80.o: libz80/z80.c
 	$(MAKE) -C libz80/codegen opcodes
@@ -39,7 +36,7 @@ emul.o: emul.c
 
 
 .PHONY: updatebootstrap
-updatebootstrap: stage xcomp.fs
+updatebootstrap: stage xcomp.fs pack
 	./stage < xcomp.fs > forth.bin
 
 .PHONY: pack
@@ -52,5 +49,4 @@ unpack:
 
 .PHONY: clean
 clean:
-	rm -f $(TARGETS) emul.o *-bin.h stage{1,2}.bin blkfs
-	$(MAKE) -C ../tools clean
+	rm -f $(TARGETS) emul.o *-bin.h blkfs
diff --git a/emul/forth.c b/emul/forth.c
index 0cfc8d2..cf4a5e9 100644
--- a/emul/forth.c
+++ b/emul/forth.c
@@ -5,7 +5,6 @@
 #include <termios.h>
 #include "emul.h"
 #include "forth-bin.h"
-#include "blkfs-bin.h"
 
 // in sync with glue.asm
 #define RAMSTART 0x900
@@ -83,13 +82,15 @@ static void iowr_blkdata(uint8_t val)
 
 int run()
 {
-    blkfp = fopen("blkfs", "r+");
-    if (blkfp) {
-        fprintf(stderr, "Using blkfs file\n");
-    } else {
-        blkfp = fmemopen((char*)BLKFS, sizeof(BLKFS), "r");
-        fprintf(stderr, "Using in-memory read-only blkfs\n");
+#ifdef BLKFS_PATH
+    fprintf(stderr, "Using blkfs %s\n", BLKFS_PATH);
+    blkfp = fopen(BLKFS_PATH, "r+");
+    if (!blkfp) {
+        fprintf(stderr, "Can't open\n");
     }
+#else
+    blkfp = NULL;
+#endif
     Machine *m = emul_init();
     m->ramstart = RAMSTART;
     m->iord[STDIO_PORT] = iord_stdio;
diff --git a/emul/stage.c b/emul/stage.c
index 7b5b3b8..48bf19b 100644
--- a/emul/stage.c
+++ b/emul/stage.c
@@ -3,7 +3,10 @@
 #include <unistd.h>
 #include "emul.h"
 #include "forth-bin.h"
-#include "blkfs-bin.h"
+
+#ifndef BLKFS_PATH
+#error BLKFS_PATH needed
+#endif
 
 /* Staging binaries
 
@@ -37,7 +40,7 @@ static int running;
 static uint16_t start_here = 0;
 static uint16_t end_here = 0;
 static uint16_t blkid = 0;
-static unsigned int blkpos = 0;
+static FILE *blkfp;
 
 static uint8_t iord_stdio()
 {
@@ -65,16 +68,22 @@ static void iowr_blk(uint8_t val)
 {
     blkid <<= 8;
     blkid |= val;
-    blkpos = blkid * 1024;
+    fseek(blkfp, blkid*1024, SEEK_SET);
 }
 
 static uint8_t iord_blkdata()
 {
-    return BLKFS[blkpos++];
+    return getc(blkfp);
 }
 
 int main(int argc, char *argv[])
 {
+    fprintf(stderr, "Using blkfs %s\n", BLKFS_PATH);
+    blkfp = fopen(BLKFS_PATH, "r+");
+    if (!blkfp) {
+        fprintf(stderr, "Can't open\n");
+        return 1;
+    }
     Machine *m = emul_init();
     m->ramstart = RAMSTART;
     m->iord[STDIO_PORT] = iord_stdio;