Authoring commits with different emails for work and personal projects

I like to store all my git repositories, of both work and personal projects, under a single directory at ~/dev. I think I’ll change this to ~/code soon, it sounds more appropriate. Anyway, back to the topic.

At the top of my ~/.gitconfig file I have configured the git user (which represents the commit author) to use my personal email address:

[user]
  name = Ilias Trichopoulos
  email = ilias.personal@gmail.com

However, when I work in git repositories of projects for my work, I want the author of my commits to have my work email address. The simplest way I found to achieve this is to dedicate a directory for all my work-related git repositories and create a separate .gitconfig file there. Then, I can conditionally include this new file in my main .gitconfig depending on which project I am working on.

In my case, I have all my work-related projects under ~/dev/company-name. I created a new .gitconfig file there where the only contents are:

[user]
  email = ilias.work@company-name.com

Git 2.13 introduced the feature of Conditional includes which allows you to include a dedicated .gitconfig file depending on where the git repository is located.

Adding the following configuration at the bottom of my main ~/.gitconfig file ensures that when I work in a git repository located at ~/dev/company-name/project1, the author of my commits will have the ilias.work@company-name.com email address.

[user]
  name = Ilias Trichopoulos
  email = ilias.personal@gmail.com

...

[includeIf "gitdir:~/dev/company-name/"]
  path = ~/dev/company-name/.gitconfig

Credits to this StackOverflow answer that showed me the way.