diff --git a/base64/GNUmakefile b/base64/GNUmakefile
new file mode 100644
index 0000000..0c88c28
--- /dev/null
+++ b/base64/GNUmakefile
@@ -0,0 +1,13 @@
+include GNUmakevars
+include GNUmakerules
+
+base64: base64.o
+	$(CC) $^ -lant -o $@
+
+clean:
+	rm -f *.o base64 core foo bar
+
+install: $(BINDIR)/base64
+
+distclean: clean
+	rm -f *.bak *.d
diff --git a/base64/base64.c b/base64/base64.c
new file mode 100644
index 0000000..4aacdb9
--- /dev/null
+++ b/base64/base64.c
@@ -0,0 +1,55 @@
+#include <ant/base64.h>
+#include <unistd.h>
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+char *cmnd;
+
+static void usage(void) {
+    fprintf(stderr, "Usage: %s [-d|-e]\n", cmnd);
+    exit(1);
+}
+
+int main(int argc, char **argv) {
+    char buf1[1024+1];
+    char buf2[1024+1];
+    enum { NONE, ENCODE, DECODE} mode = NONE;
+    int c;
+    int r1, r2;
+    cmnd = argv[0];
+    while ((c = getopt(argc, argv, "de")) != EOF) {
+	switch(c) {
+	    case 'd':
+		mode = DECODE;
+		break;
+	    case 'e':
+		mode = ENCODE;
+		break;
+	    case '?':
+		usage();
+	    default:
+		assert(0);
+	}
+    }
+    switch(mode) {
+	case NONE:
+	    usage();
+	case ENCODE:
+	    while ((r1 = fread(buf1, 1, 57, stdin)) > 0) {
+		r2 = base64_encode(buf2, sizeof(buf2), buf1, r1, 76);
+		fwrite(buf2, 1, r2, stdout);
+		putchar('\n');
+	    }
+	    break;
+	case DECODE:
+	    while (fgets(buf1, sizeof(buf1), stdin)) {
+		r1 = strlen(buf1);
+		if (buf1[r1-1] == '\n') r1--;
+		r2 = base64_decode(buf2, sizeof(buf2), buf1, r1);
+		fwrite(buf2, 1, r2, stdout);
+	    }
+    }
+    return 0;
+}