diff --git a/tools/bash-completion.sh b/tools/bash-completion.sh
new file mode 100644
index 0000000..9f65c67
--- /dev/null
+++ b/tools/bash-completion.sh
@@ -0,0 +1,55 @@
+#!/bin/bash
+# Copyright 2012 the V8 project authors. All rights reserved.
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+#       notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+#       copyright notice, this list of conditions and the following
+#       disclaimer in the documentation and/or other materials provided
+#       with the distribution.
+#     * Neither the name of Google Inc. nor the names of its
+#       contributors may be used to endorse or promote products derived
+#       from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+# Inspired by and based on:
+# http://src.chromium.org/viewvc/chrome/trunk/src/tools/bash-completion
+
+# Flag completion rule for bash.
+# To load in your shell, "source path/to/this/file".
+
+v8_source=$(readlink -f $(dirname $BASH_SOURCE)/..)
+
+_v8_flag() {
+  local cur defines targets
+  cur="${COMP_WORDS[COMP_CWORD]}"
+  defines=$(cat src/flag-definitions.h \
+    | grep "^DEFINE" \
+    | grep -v "DEFINE_implication" \
+    | sed -e 's/_/-/g')
+  targets=$(echo "$defines" \
+    | sed -ne 's/^DEFINE-[^(]*(\([^,]*\).*/--\1/p'; \
+    echo "$defines" \
+    | sed -ne 's/^DEFINE-bool(\([^,]*\).*/--no\1/p'; \
+    cat src/d8.cc \
+    | grep "strcmp(argv\[i\]" \
+    | sed -ne 's/^[^"]*"--\([^"]*\)".*/--\1/p')
+  COMPREPLY=($(compgen -W "$targets" -- "$cur"))
+  return 0
+}
+
+complete -F _v8_flag -f d8