docker-squash is a Go app that merges layers to make images smaller. The savings using
docker-squash depends on how many layers it can effectively squash, so mileage may vary.
Let's squash richardtylee/railsapp and tag it as squashed:
REPOSITORY TAG VIRTUAL SIZE
richardtylee/railsapp squashed 1.119 GB
richardtylee/railsapp latest 1.141 GB
So we can save about 22 MB.