Managing multiple SSH GitHub identities

Now I’m involved in multiple businesses, I’m finding I need to frequently juggle multiple SSH key pairs (aka identities) with choose your favourite git offering (e.g. GitHub). When I push and pull to origins on the same machine, I need to alternate the identities I use.

The best approach is to use an SSH config file to define host aliases. This lets you seamlessly use different keys without manually switching anything.

• Set Up SSH Config
• How to Use It
• Per-Repo Git Identity

Set Up SSH Config

Edit (or create) ~/.ssh/config:

# Personal GitHub
Host github-personal
    HostName github.com
    User git
    IdentityFile ~/.ssh/id_ed25519_personal
    IdentitiesOnly yes

# Work GitHub
Host github-work
    HostName github.com
    User git
    IdentityFile ~/.ssh/id_ed25519_work
    IdentitiesOnly yes

How to Use It

When cloning or setting remotes, use your alias instead of github.com:

# Personal repo
git clone git@github-personal:myusername/repo.git

# Work repo
git clone git@github-work:mycompany/repo.git

For existing repos, update the remote:

git remote set-url origin git@github-personal:myusername/repo.git

Per-Repo Git Identity

You’ll also want different commit author info. In each repo:

git config user.name "Your Name"
git config user.email "you@example.com"

Or set a global default and override per-repo, or use conditional includes in ~/.gitconfig:

[includeIf "gitdir:~/work/"]
    path = ~/.gitconfig-work

Then ~/.gitconfig-work contains your work name/email.

This approach is clean because the identity is “baked into” each repo’s remote URL—no need to remember to switch anything when you push or pull.