Multiple git accounts on one device

git
Some guidelines on how to organise projects and configure git to have a smooth experience when working with multiple accounts on one device.
Published

September 10, 2024

The notes below are guidelines I documented for myself in the future after consulting mainly this post and its comments suggesting improvements. This is especially useful if you want to set-up multiple work / personal git accounts on one device as smoothly as possible (i.e. no hassles regarding private repo authorisation, account-level git settings, account-level commit metadata etc.).

Let’s go through an example.

Aim

The aim of a smooth git setup is twofold

1) Authorization for private repos
You should be able to interact with private repos using the right authorization key. For example, if you want to clone a private personal or work repo, git should know what SSH to use.

2) Configuration of git behavior
Git should use the right configuration depending on the work / personal account. For example, if you are working on a work project, git should behave with different options related to merge strategy, commit metadata (email, username) etc.

Folder setup

To select the correct authorization keys and configuration settings, work and personal projects should be organized into separate directories, as shown below

/Users/sinan
├── work
│   ├── ml_project
│   └── rag_app
└─- personal
    ├── learnings
    └── ds_utils_pkg

SSH keys and configuration

Create an SSH key for both accounts.

Note that you could use a single key for multiple accounts, but this is not recommended as it complicates access management and key rotation.

ssh-keygen -t ed25519 -f ~/.ssh/work
ssh-keygen -t ed25519 -f ~/.ssh/personal

Next, create an SSH config file that points to the correct SSH keys

~/.ssh/config

Host github.com-personal
  HostName github.com
  User sinanpl
  IdentityFile ~/.ssh/personal

Host github.com-work
  HostName github.com
  User sinan-work
  IdentityFile ~/.ssh/work

At this point, you will be able to interact with private repos by using the work or personal host. Let’s say you have a private repo in your personal account you want to pull, you can use git clone git@github.com-personal:sinanpl/ds_utils_pkg.git. Similarly, you can use the github.com-work suffix for pulling private work repos. This is not ideal, but it can be improved in the following steps.

Account-level git config

Create separate .git.conf files for your work and personal account such that

  1. the host can be altered from github.com-xxx to github.com
  2. the account level settings can be configured such as:
    • user name
    • user email
    • merge strategy
    • default branch name
    • …

In the end, the files should look like:

~/personal/.git.conf

[url "git@github.com-personal"]
  insteadOf = git@github.com

[user]
  email = sinan@mail.com

~/work/.git.conf

[url "git@github.com-personal"]
  insteadOf = git@github.com

[user]
  email = sinan@work.com

# example option
# [pull]
#   rebase = false

Global git configuration

Finally, you want to have a global configuration that dispatches to the correct configuration (and authorization) when working from a specific folder.

Create or update your global with the following

[includeIf "gitdir:~/work/"]
    path = ~/work/.git.conf
[includeIf "gitdir:~/personal/"]
    path = ~/personal/.git.conf

Result

  • Authorisation for work and personal accounts is separated
  • Cloning a private work repo from within your personal folder is not possible and vice versa.
  • Cloning private repos from the work or personal host no longer requires a suffix.
  • Git behaves differently depending on account specification