If Time Machine regularly does its automated backups, transferring 10+ GB of hidden Docker data over WiFi will hurt productivity.

Exclude Docker from Time Machine

Robust solution is to exclude Docker’s data paths from backups in System Preferences > Time Machine > Options....

Depending on what kind of Docker setup it is, one (or both) of the following paths should be added to excluded paths in Time Machine options:

  • Docker Machine

      ~/.docker
    
  • Docker Desktop (formerly Docker for Mac)

      ~/Library/Containers/com.docker.docker/Data
    

Backup gains from Docker containers

For many developers the idea to exclude Docker from Time Machine backups will result in a sizable backup reduction:

$ du -h ~/.docker
 ...
 20G	/Users/ain/.docker
$ du -h ~/Library/Containers/com.docker.docker/Data
 ...
 50G	/Users/ain/Library/Containers/com.docker.docker/Data