Introducing Butler

16 Apr 2015

I am a supremely lazy person. With the rise of wrappers like virtualenv, bundler, foreman, etc, I find the shell commands I need to remember getting really long. Things like:

Run only unit tests

foreman run python test.py unit

Run the database migrations

bundle exec rake db:migrate

Start my java app

java -jar target/my-java-app-0.1.5.jar

I figure someone else should be remembering those for me. Ideally I should only need to remember migrate to migrate the db and unit to run the unit tests.


The Butler is a small command line tool for reducing the number of keystrokes I need to make while working.

The code can be found on github.

How to use Butler

It’s pretty easy to get started. Just install it from brew:

brew install michaeldfallen/formula/butler

Then create a butlerfile with a command in it:

echo "hello: echo \"Hello, world!\"" >> butlerfile

Your butlerfile will look like this:

hello: echo "Hello, world!"

Now you can ask Butler to run the command:

butler hello

And Butler will execute the script behind it for you.

Safety checks

Since running commands from a file isn’t entirely safe, especially if teams use Butler together, you’ll want to be certain that the command is safe.

To do this Butler will show you the script and ask if it’s ok to run the first time. Any time the script, or the name of the command, changes Butler will ask again if it’s safe to run. So you won’t get caught by a sneaky rm -rf ~.


Any commands in your butlerfile will autocomplete in both Bash and Zsh, just add this to your ~/.zshrc or ~/.bashrc:

source "$(butler --init-completion)"

And you get sexy tab completion:

So Happy!

I’ve been using Butler over the last week and it’s made me so happy. No more long confusing commands.

One other thing I’ve noticed is that the butlerfile makes for useful documentation. If anyone asks “How do you run the tests?” I can look in that projects butlerfile and show them.

This post has been edited on 17/4/2015. You can read the history of this post on github.