!!! For M1/M2 apple silicon see this comment:
For MacOS | Mojave | High Sierra
brew upgrade gnupg
brew install pinentry-mac
echo "pinentry-program /usr/local/bin/pinentry-mac" >> ~/.gnupg/gpg-agent.conf
killall gpg-agent && gpg-agent --daemon
git config --global gpg.program gpg
git config --global commit.gpgsign true
GPG Git integration on macOS Ventura (and newer versions):
Here are all steps combined to setup and integrate GPG and Git on the latest macOS:
Thanks to @Peredery and @shaunsim15!