diff --git a/platform/vax/mkmopheader.c b/platform/vax/mkmopheader.c
new file mode 100644
index 00000000..55b72203
--- /dev/null
+++ b/platform/vax/mkmopheader.c
@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) 2019 Travis Geiselbrecht
+ *
+ * Use of this source code is governed by a MIT-style
+ * license that can be found in the LICENSE file or at
+ * https://opensource.org/licenses/MIT
+ */
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+
+// Copy input file to output, prepending a MOP header enough to satisfy
+// the mopd daemon used to netboot an image on a VAX.
+//
+// Developed against mopd daemon at https://github.com/qu1j0t3/mopd
+
+int main(int argc, char **argv) {
+    if (argc < 3) {
+        printf("not enough args");
+usage:
+        printf("usage %s <infile> <outfile>\n", argv[0]);
+        return 1;
+    }
+
+    FILE *infp = fopen(argv[1], "rb");
+    if (!infp) {
+        printf("error opening file %s\n", argv[1]);
+        goto usage;
+    }
+
+    FILE *outfp = fopen(argv[2], "wb");
+    if (!infp) {
+        printf("error opening file %s\n", argv[2]);
+        goto usage;
+    }
+
+    // get length of the input file
+    fseek(infp, 0, SEEK_END);
+    long int len = ftell(infp);
+    //printf("input file length %#lx\n", len);
+    rewind(infp);
+
+    // round up to next 512 byte boundary
+    len = (len + 511) / 512 * 512;
+    //printf("rounded %#lx\n", len);
+
+    // generate the header
+    char buffer[512];
+    memset(buffer, 0, sizeof(buffer));
+
+    // main header
+    uint16_t isd = 0xd4;
+    uint16_t iha = 0x30;
+    uint8_t hbcnt = 1;
+    uint16_t image_type = 0xffff;
+    memcpy(buffer + 0, &isd, sizeof(isd));
+    memcpy(buffer + 2, &iha, sizeof(iha));
+    memcpy(buffer + 16, &hbcnt, sizeof(hbcnt));
+    memcpy(buffer + 510, &image_type, sizeof(image_type));
+
+    // image header (at offset isd)
+    uint16_t isize = len / 512;
+    uint16_t load_addr = 0 / 512;
+
+    memcpy(buffer + isd + 2, &isize, sizeof(isize));
+    memcpy(buffer + isd + 4, &load_addr, sizeof(load_addr));
+
+    // something else at iha
+    uint32_t xfer_addr = 0;
+    memcpy(buffer + iha, &xfer_addr, sizeof(xfer_addr));
+
+    // write the header out
+    fseek(outfp, 0, SEEK_SET);
+    fwrite(buffer, sizeof(buffer), 1, outfp);
+
+    // copy the input file to the output file
+    int written = 0;
+    while (!feof(infp)) {
+        char buf[512];
+        int count = fread(buf, 1, sizeof(buf), infp);
+        if (count == 0) {
+            break;
+        }
+        fwrite(buf, 1, count, outfp);
+        written += count;
+    }
+
+    // pad it out with zeros
+    while (written < len) {
+        char zero = 0;
+        fwrite(&zero, 1, 1, outfp);
+        written++;
+    }
+
+    fclose(infp);
+    fclose(outfp);
+
+    return 0;
+}
diff --git a/platform/vax/rules.mk b/platform/vax/rules.mk
index 331a6a5d..1199c6c5 100644
--- a/platform/vax/rules.mk
+++ b/platform/vax/rules.mk
@@ -37,17 +37,21 @@ KERNEL_LOAD_OFFSET := 0x00100000 # loaded 1MB into physical space
 #KERNEL_BASE = 0x80000000
 KERNEL_BASE = 0
 
-#LINKER_SCRIPT += \
-#	$(BUILDDIR)/system-onesegment.ld
+# tool to add a mop header to the output binary to be net bootable
+MKMOPHEADER := $(call TOBUILDDIR,$(LOCAL_DIR)/mkmopheader)
+$(MKMOPHEADER): $(LOCAL_DIR)/mkmopheader.c
+	@$(MKDIR)
+	$(NOECHO)echo compiling host tool $@; \
+	cc -O -Wall $< -o $@
 
-# python script to generate the zynq's bootrom bootheader
-#MKBOOTHEADER := $(LOCAL_DIR)/mkbootheader.py
-#EXTRA_BUILDDEPS += $(BOOTHEADERBIN)
-#GENERATED += $(BOOTHEADERBIN)
+GENERATED += $(MKMOPHEADER)
 
-#$(BOOTHEADERBIN): $(OUTBIN) $(MKBOOTHEADER)
-#	@$(MKDIR)
-#	$(NOECHO)echo generating $@; \
-#	$(MKBOOTHEADER) $(OUTBIN) $@
+$(OUTBIN).mop: $(MKMOPHEADER) $(OUTBIN)
+	@$(MKDIR)
+	$(NOECHO)echo generating $@; \
+	$(MKMOPHEADER) $(OUTBIN) $@
+
+EXTRA_BUILDDEPS += $(OUTBIN).mop
+GENERATED += $(OUTBIN).mop
 
 include make/module.mk