Skippable

Skippable helps you skip slow commands unless certain files changed. This can be handy on CI, where valuable time, money, and CO₂ are often wasted by repeatedly running the same command when nothing changed.

For example License Finder takes ~45 seconds to run on a project with Ruby gems and NPM dependencies. In this example there's no need to check the licenses if the dependency lockfiles didn't change.

Add Skippable to your Gemfile:

group :development do
  gem "skippable", require: false
end

Setup a .skippable.yml config file with one or more tasks:

tasks:
  expensive_op:
    command: bundle exec my_slow_command
    paths:
      - lockfile_a
      - lockfile_b

Run the task using skippable:

bundle exec skippable expensive_op

• If the cache was cold OR the lockfiles changed, the specified command will be run
• If the cache is warm, and the lockfiles haven't changed, the command will be skipped

Finally, cache the following directory to persist state across builds:

tmp/skippable

# .skippable.yml
tasks:
  license_finder:
    command: bundle exec license_finder
    paths:
      - Gemfile.lock
      - yarn.lock

Invocation:

bundle exec skippable license_finder