MANAGING GIT CREDENTIALS FOR MULTIPLE GITHUB ACCOUNTS ON ONE MACHINE

Git doesn't natively give you a clean way to manage multiple profiles on a single machine. this becomes a problem when you want to use one machine for both work and personal projects i.e two identities, two github accounts, and things start breaking in subtle ways

commits may use the wrong email, authentication fails for private repos, or ssh and https setups interfere with each other

the approach here is to separate concerns cleanly: work uses ssh, personal uses https, and folder-based git config handles which identity is active

i'm using macOS + zsh. the commands are identical on bash. on linux the setup is the same except the credential helper — use libsecret instead of osxkeychain. on windows, use git bash or wsl and swap osxkeychain for manager (git credential manager).

1.0 git identity vs authentication

these are two different things. user.name and user.email define who authored the commit. ssh and https define how you authenticate with github. you can commit with one email and authenticate with a completely different account — git doesn't enforce a relationship between the two

github uses the commit email to link commits to your profile. if the email matches your account, commits show up in your contributions. if not, they still work but aren't attributed to you.

git supports conditional config to pick an identity by directory:

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

this lets ~/work use your work identity and ~/personal use your personal one automatically.

2.0 setup

start by creating the two folders at the root of home; you'll put your work related repos inside the ~/work and likewise personal projects inside the ~/personal:

keep the folder names to your convenience

mkdir -p ~/work
mkdir -p ~/personal

set your global git identity to your work account; this acts as the default:

git config --global user.name "your name"
git config --global user.email "you@company.com"

create a personal config override at ~/.gitconfig-personal. open it with nano:

nano ~/.gitconfig-personal

paste this in:

[user]
    name = your name
    email = yourpersonal@email.com

save and exit: ctrl + o to overwrite → enter to confirm → ctrl + x to close

then open your global git config to link it:

nano ~/.gitconfig

add this at the bottom:

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

save and exit the same way: ctrl + o → enter → ctrl + x

3.0 work — ssh

generate a dedicated ssh key for your work account:

ssh-keygen -t ed25519 -C "you@company.com" -f ~/.ssh/id_ed25519_work

add it to the ssh agent:

eval "$(ssh-agent -s)"
ssh-add ~/.ssh/id_ed25519_work

copy the public key and add it to your work github account under settings → ssh keys:

cat ~/.ssh/id_ed25519_work.pub

test the connection:

ssh -T git@github.com

clone work repos over ssh:

cd ~/work
git clone git@github.com:company/repo.git

4.0 personal — https

enable credential storage so you're not prompted every time:

git config --global credential.helper osxkeychain

create a personal access token on github under settings → developer settings → personal access tokens (classic). select repo scope if you need private repo access

clone personal repos over https when prompted, use your github username and the token as the password:

cd ~/personal
git clone https://github.com/username/repo.git

5.0 common issues

wrong email in commits

• run git config --show-origin user.email to see where the value is coming from. if there's a local override conflicting, clear it with git config --local --unset user.email.

https keeps asking for login

• check that the credential helper is set with git config --global credential.helper. if it's empty, re-run the osxkeychain command above.

ssh not working

• run ssh-add -l to check if the key is loaded. if not, run ssh-add ~/.ssh/id_ed25519_work again.

folder config not applying

• make sure the path in includeIf ends with a trailing slash (~/personal/) and that you're inside an initialized git repo.