Files that (mostly) start with a dot and do configurish things.

defaults write com.apple.Terminal AppleShowScrollBars -string WhenScrolling

1. Enable the 1Password SSH agent.
2. Create an easier-to-remember symlink for the agent:

   mkdir -p $HOME/.1password; \
   ln -s $HOME/Library/Group\ Containers/2BUA8C4S2C.com.1password/t/agent.sock $HOME/.1password/agent.sock

3. Create a LaunchAgent ($HOME/Library/LaunchAgents/com.1password.SSH_AUTH_SOCK.plist) that replaces the default macOS agent socket with the 1Password agent socket:

   <?xml version="1.0" encoding="UTF-8"?>
   <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http:https://www.apple.com/DTDs/PropertyList-1.0.dtd">
   <plist version="1.0">
   <dict>
       <key>Label</key>
       <string>com.1password.SSH_AUTH_SOCK</string>
       <key>ProgramArguments</key>
       <array>
           <string>/bin/sh</string>
           <string>-c</string>
           <string>/bin/ln -sf $HOME/.1password/agent.sock \$SSH_AUTH_SOCK</string>
       </array>
       <key>RunAtLoad</key>
       <true/>
   </dict>
   </plist>

4. Configure SSH ($HOME/.ssh/config) to use the 1Password agent:

   Host *
       IdentityAgent "$HOME/.1password/agent.sock"
   

5. Configure Git ($HOME/.gitconfig) to sign commits with the 1Password agent:

   [commit]
       gpgsign = true
   [gpg]
       format = ssh
   [gpg "ssh"]
       program = "/Applications/1Password.app/Contents/MacOS/op-ssh-sign"
   

1. Mount /run/host-services/ssh-auth.sock:/run/host-services/ssh-auth.sock
2. Set the SSH_AUTH_SOCK environment variable to /run/host-services/ssh-auth.sock
3. Add required hosts to the container user's $HOME/.ssh/known_hosts.