I recently released hitch 0.6, a complete rewrite of the original hitch. We now have a test suite! :-) hitch is a Git author attribution helper for pair programmers. It will modify your git author name and email to reflect who you are pairing with.

The itch we’re scratching

Les Hill originally wrote:

Pair programming does present some unique problems, one that we encountered at Hashrocket was commit attribution: a commit message would be identified with one member of the pair only. This is not exactly tragic, but from the perspective of a passionate developer, having commit credit (and accountability) is a critical and visible part of the ethos.

Tim Pope had the brilliant idea of using a group email address with tags (such as group+you@example.com) to identify the commits a pair made to git. A little bash script fu lead to a nifty command line utility that let us track pairs with our git commits. With that script as a starting point, Ro Samour wrote a pure ruby implementation: hitch

This is what a typical hitch commit message looks like in your terminal:

commit e518dd0637e7d1d77d3bd79a645e5d0bc93eae2d
Author: Philip J. Fry and Turanga Leela <planex+fry+leela@example.com>
Commit: Bender Pairing Station <bender@example.com>

    Fix infite loop in empathy chip

This is a commit message from hitch on github:

Getting started

You will need to install the hitch gem:

% gem install hitch

Or rvm users should copy and paste the following into your terminal:

for x in $(rvm list strings)
do
  rvm use $x@global && gem install hitch
done

Then you will need to add a shell function to your .bashrc or .zshrc:

hitch() {
  command hitch "$@"
  if [[ -s "$HOME/.hitch_export_authors" ]]; then
    source "$HOME/.hitch_export_authors"
  fi
}
alias unhitch='hitch -u'
# Uncomment to persist pair info between terminal instances
# hitch

Alternatively, you can also run the following:

% hitch --setup >> ~/.bashrc

rvm users: (that should be everyone ;-) You should add the shell commands from above after you source the rvm scripts.

Once that’s done, source the ~/.bashrc or open a new terminal and you’re good to go.

The Group Email

You will need a group email account with a service such as GMail or GoogleApps GMail that allows email tags¹ (as an example, twitter is a tag in this email address bender+twitter@example.com which is considered to be the same email address as bender@example.com):

At Hashrocket we use a Gravatar for our group email account so that the commits show the custom gravatar along with our commit messages. For every pair, we register a new gravatar and associate it with a tagged email address of the form:

dev+github_user1+github_user2@example.com

The github usernames should appear in the local part of the address in alphabetical order after the group address local part, each github username seperated by a +.

Using hitch

To pair with another developer whose github username is pair:

% hitch fry leela

hitch will prompt you if it does not recognize github username of your pair and save it for later use.

To unpair and code solo:

% hitch -u

or

% unhitch

To see who you are currently paired with:

% hitch