diff --git a/bundle.sh b/bundle.sh
new file mode 100755
index 0000000..974d8d1
--- /dev/null
+++ b/bundle.sh
@@ -0,0 +1,90 @@
+#!/bin/bash
+
+# single-file library bundler
+# https://github.com/nothings/stb
+# https://github.com/nothings/stb/blob/master/docs/stb_howto.txt
+
+set -o nounset -o pipefail -o errexit
+
+URL=${URL-https://github.com/rootmos/libr}
+VERSION=${VERSION-$(git rev-parse HEAD)}
+OUTPUT=/dev/stdout
+while getopts "o:-" OPT; do
+    case $OPT in
+        o) OUTPUT=$OPTARG ;;
+        -) break ;;
+        ?) exit 2 ;;
+    esac
+done
+shift $((OPTIND-1))
+
+SCRIPT_DIR=$(readlink -f "$0" | xargs dirname)
+BASE_DIR=${BASE_DIR-$SCRIPT_DIR}
+SRC=${SRC-$BASE_DIR/src}
+INC=${INC-$BASE_DIR/include/r}
+
+TMP=$(mktemp -d)
+trap 'rm -rf $TMP' EXIT
+
+readarray -t ALL_MODULES < <(find "$SRC" -name "*.c" -exec basename --suffix=.c {} \;)
+
+if [ $# -gt 0 ]; then
+    for i in "$@"; do
+        echo "$i" >> "$TMP/choices"
+    done
+else
+    DIALOG_ARGS=()
+    for m in "${ALL_MODULES[@]}"; do
+        DIALOG_ARGS+=("$m" "$m" "off")
+    done
+    dialog --separate-output --no-tags --checklist "select modules" 0 0 0 \
+        "${DIALOG_ARGS[@]}" 2>"$TMP/choices"
+fi
+
+is_selected() {
+    grep -cFxq "$@" "$TMP/choices"
+}
+
+depends() {
+    if is_selected "$1" && ! is_selected "$2"; then
+        echo "$2" >> "$TMP/choices"
+    fi
+}
+
+depends "stopwatch" "fail"
+depends "stopwatch" "logging"
+depends "xorshift" "fail"
+depends "mark" "fail"
+depends "mark" "logging"
+depends "test" "util"
+depends "test" "fail"
+depends "logging" "fail"
+depends "fail" "logging"
+depends "logging" "util"
+
+readarray -t MODULES < "$TMP/choices"
+
+echo 1>&2 "included modules: ${MODULES[*]}"
+
+echo >"$OUTPUT" "// libr ($VERSION) ($URL) ($(date -Is))"
+echo >>"$OUTPUT" "// modules: ${MODULES[*]}"
+echo >>"$OUTPUT" ""
+
+echo >>"$OUTPUT" "#ifndef LIBR_HEADER"
+echo >>"$OUTPUT" "#define LIBR_HEADER"
+for m in "${MODULES[@]}"; do
+    echo >>"$OUTPUT" ""
+    echo >>"$OUTPUT" "// libr: $m.h"
+    tail -n+3 "$INC/$m.h" >>"$OUTPUT" # HACK: remove pragma once directive
+done
+echo >>"$OUTPUT" ""
+echo >>"$OUTPUT" "#endif // LIBR_HEADER"
+
+echo >>"$OUTPUT" "#ifdef LIBR_IMPLEMENTATION"
+for m in "${MODULES[@]}"; do
+    echo >>"$OUTPUT" ""
+    echo >>"$OUTPUT" "// libr: $m.c"
+    grep -vx '#include "r/\w\+.h"' "$SRC/$m.c" >>"$OUTPUT"
+done
+echo >>"$OUTPUT" ""
+echo >>"$OUTPUT" "#endif // LIBR_IMPLEMENTATION"
diff --git a/src/util.c b/src/util.c
index ba90325..ca82128 100644
--- a/src/util.c
+++ b/src/util.c
@@ -1,4 +1,4 @@
-#include <r.h>
+#include "r/util.h"
 
 #include <assert.h>
 #include <fcntl.h>