packs are a specification for an extensible packaging system to help modularize Ruby applications.

A pack (short for package) is a folder of Ruby code with a package.yml at the root that is intended to represent a well-modularized domain.

This gem provides a development CLI, bin/packs, to make using packs easier.

By default, this library will look for packs in the folder packs/*/package.yml (as well as nested packs at packs/*/*/package.yml). To change where packs are located, create a packs.yml file in the root of your project:

pack_paths:
  - "{packs,utilities,deprecated}/*" # packs with multiple roots!
  - "{packs,utilities,deprecated}/*/*" # nested packs!
  - gems/* # gems can be packs too!

The rest of the rubyatscale ecosystem is intended to help make using packs and improving the boundaries between them more clear.

Here are some example integrations with packs:

• packs-specification is a low-dependency gem that allows your production environment to query simple information about packs
• packs-rails can be used to integrate packs into your rails application
• rubocop-packs contains cops to improve boundaries around packs
• packwerk and packwerk-extensions help you describe and constrain your package graph in terms of dependencies between packs and pack public API
• code_ownership gives your application the capability to determine the owner of a pack
• pack_stats makes it easy to send metrics about pack adoption and modularization to your favorite metrics provider, such as DataDog (which has built-in support).

A ruby gem is the Ruby community solution for packaging and distributing Ruby code. A gem is a great place to start new projects, and a great end state for code that's been extracted from an existing codebase. packs are intended to help gradually modularize an application that has some conceptual boundaries, but is not yet ready to be factored into gems.

1. Add the gem to your Gemfile and do a bundle install

gem 'packs-rails'
gem 'packs'

2. Initialize packwerk

bundle binstub packwerk
bin/packwerk init

3. Make sure to run bundle binstub packs to generate bin/packs within your application.

bin/packs help [COMMAND]

bin/packs create packs/your_pack

bin/packs add_dependency packs/from_pack packs/to_pack

Use this to add a dependency between packs.

When you use bin/packs add_dependency packs/from_pack packs/to_pack, this command will modify packs/from_pack/package.yml's list of dependencies and add packs/to_pack.

This command will also sort the list and make it unique.

bin/packs list_top_violations type [ packs/your_pack ]

Possible types are: dependency, privacy, layer.

Want to see who is depending on you? Not sure how your pack's code is being used in an unstated way? You can use this command to list the top dependency violations.

Want to create interfaces? Not sure how your pack's code is being used? You can use this command to list the top privacy violations.

Want to focus on the big picture first? You can use this command to list the top layer violations.

If no pack name is passed in, this will list out violations across all packs.

bin/packs make_public path/to/file.rb path/to/directory

This moves a file or directory to public API (either the app/public folder or the pack's specified public path).

Make sure there are no spaces between the comma-separated list of paths of directories.

bin/packs move packs/destination_pack path/to/file.rb path/to/directory

This is used for moving files into a pack (the pack must already exist). Note this works for moving files to packs from the monolith or from other packs

Make sure there are no spaces between the comma-separated list of paths of directories.

bin/packs lint_package_todo_yml_files

bin/packs lint_package_yml_files [ packs/my_pack packs/my_other_pack ]

bin/packs validate

bin/packs check [ packs/my_pack ]

bin/packs update

bin/packs get_info [ packs/my_pack packs/my_other_pack ]

bin/packs rename

bin/packs move_to_parent packs/child_pack packs/parent_pack

bin/packs move_to_folder packs/foo some/directory

Releases happen automatically through github actions once a version update is committed to main.

To keep things organized, here are some recommended homes:

https://github.com/rubyatscale/packs/issues

https://github.com/rubyatscale/packs/discussions/categories/q-a

https://github.com/rubyatscale/packs/discussions/categories/general

https://github.com/rubyatscale/packs/discussions/categories/ideas

https://github.com/rubyatscale/packs/discussions/categories/show-and-tell