Multiple scoped Git identities and configurations (eg: personal and professional emails, multiple keys, etc.). Ideal for developers who use the same computer for multiple work and personal projects. Credit: https://stackoverflow.com/a/49154229

.company-a.gitconfig

# Example configuration for Company A
# This will only be applied for Git operations within ~/code/company-a-work/

# Within this scope, values below will overwrite the corresponding ones in the global .gitconfig
# Only mention configs that overwrite or elaborate on the global .gitconfig

[user]
	name = Dr. Betty White
	email = [email protected]
	signingkey = yyyyyyyyyyyyyyyy
[commit]
	gpgsign = true  # Company A prefers that all commits are signed.

.company-b.gitconfig

# Example configuration for Company B
# This will only be applied for Git operations within ~/code/company-b-work/

# Within this scope, values below will overwrite the corresponding ones in the global .gitconfig
# Only mention configs that overwrite or elaborate on the global .gitconfig

[user]
	name = Dr. Betty White, CTO
	email = [email protected]
	signingkey = zzzzzzzzzzzzzzzz

.gitconfig

# Global .gitconfig file located in your home folder.
# Put the most private/generalized configuration here as the global defaults.

# Configurations that are repeated (for example within an include - introduced in Git 2.x) will be overwritten by successive values.

[user]
	name = Betty White
	email = [email protected]
	signingkey = xxxxxxxxxxxxxxxx

# Add all other global configuration blocks here, BEFORE the includes.

# These configuration files are only included for Git operations within the specified directory, eg: "gitdir/i:path/to/scope/"
[includeIf "gitdir/i:~/code/company-a-work/"]
	# Path to the Company A config file
	path = .company-a.gitconfig
[includeIf "gitdir/i:~/code/company-b-work/"]
	# Path to the Company B config file
	path = .company-b.gitconfig