I code for work and I code for fun. When I do it for fun I use my personal email address as identity in Git, but when I do it for work I am often required to use my work email. For a long time my solution was to simply to set my working email in the .gitconfig of my working machine. That worked for most cases (I usually tend to only code for work on my work machine) and as the only pain point seemed to be my dotfiles, I simply accepted the pain of copy-pasting things around as a necessary evil and moved on with my life.

However, it turns out that there's a better way to handle multiple identities in Git: enter conditional configuration! Basically you can tell Git to include a different .gitconfig depending on a certain condition (e.g. when the .git directory matches a certain path). So for my specific case I simply changed my .gitconfig to like something like this:

[user]
    name = <first name> <last name>
    email = <work email address>
[includeIf "gitdir:~/Projects/personal/"]
    path = .gitconfig-personal

and then in the .gitconfig-personal I added

[user]
    name = <first name> <last name>
    email = <personal email address>

and now every time I work on a repo in the personal/ folder the work [user] block gets automagically overridden by the personal one. No more weird copy pasting around!

Gotchas

• This requires Git 2.13+ to work.
• The last slash of the gitdir path matters! If you forget it, it won't work.
• ../ gets matched literally, so don't use that if you want to refer to the parent folder.

References

• Conditional configuration in Git docs