jwl, a build and release tool for pure-Ruby gems

jwl is a tool for building and publishing pure-Ruby gems.

Features:

• signs in to a gem host
• builds gems
• cleans up after itself (if you ask it to)
• can publish gems to GitHub Releases
• will eventually be able to publish gems to gem hosts
• packing an entire (pure-Ruby) gem into a single file

Things jwl is not going to do:

• jwl will not support gems with native extensions.
• jwl will not handle every edge case.
• jwl will not manage locally-installed gems.

If you like jwl and use Python, be sure to check out bork.

Installation

I'm hoping to provide single-file executables that bundle the entire gem, akin to Python's ZipApps.

Usage

The basic commands you will need are:

• jwl signin / jwl signout: sign in or out of a gem host.
• jwl build: build a gem, with the output in ./build/.
• jwl clean: removes things created by jwl build.
• jwl release: builds and publishes a release to all configured services.

More advanced features:

• jwl pack: pack an entire gem into ./build/pack/#{gem_name}.rb.

Basic Usage

puppy@cerberus:~/okay$ jwl signin
Host: https://rubygems.org
Username: duckinator
Password:
OTP:
Please choose which scopes you want your API key to have:
index_rubygems [Y/n]
push_rubygem [y/N] y
yank_rubygem [y/N]
Saved key with name "jwl--cerberus-puppy-2026-01-27T103358" and scopes:
- index_rubygems
- push_rubygem
puppy@cerberus:~/okay$ jwl build
Name:    okay
Version: 12.0.4

Output:  /home/puppy/okay/build/okay-12.0.4.gem
puppy@cerberus:~/okay$ gem install build/okay-12.0.4.gem
Successfully installed okay-12.0.4
1 gem installed
puppy@cerberus:~/okay$

Creating A Release

jwl can not currently publish to gem hosts.

If you want to publish to GitHub Releases, you first need to add the following to your gemspec:

  spec.metadata["github_repo"] = "https://github.com/EXAMPLE_USER/EXAMPLE_REPO"

If you have JWL_GITHUB_TOKEN set to a GitHub Access Token, jwl release will publish to GitHub Releases:

puppy@cerberus:~/okay$ jwl release
Building gem...
No gem host specified. Set spec.metadata["allowed_push_host"] in your gemspec to release to a gem host.
Preparing GitHub Release.
Creating GitHub release 12.0.4 as a draft (commit=78d268e804246686182d9e53fc24a84abe5f9caa)
  Adding asset okay-12.0.4.gem to release (original file: /home/puppy/okay/build/okay-12.0.4.gem)
Publishing GitHub Release.
puppy@cerberus:~/okay$

Packed Gems

Packing a gem creates a single Ruby file that contains the entirety of a gem.

Your gem needs to:

• not use compiled extensions (no C or Rust, just Ruby and data files)
• have a single gemspec in the directory you run jwl from
• have a single executable specified in your gemspec

When you run jwl pack, creates a pure-Ruby unpacker, and appends a JSON object to the end of it.

puppy@cerberus:~/jwl$ ruby -Ilib exe/jwl pack
build/pack/jwl.rb
puppy@cerberus:~/jwl$ mv build/pack/jwl.rb ~/jwl.rb
puppy@cerberus:~/jwl$ chmod +x ~/jwl.rb
puppy@cerberus:~/jwl$ cd
puppy@cerberus:~$ ./jwl.rb
Usage: jwl [COMMAND] [OPTIONS] [ARGS...]

Commands
  jwl signin      # Sign in to the specified gem server.
  jwl signout     # Sign out from configured gem host
  jwl build       # Builds a Gem from the provided gemspec.
  jwl clean       # Clean up build/pack artifacts.
  jwl pack        # Pack a gem into a single file.
  jwl release     # Build and release a gem.
  jwl help        # Print this help text.
puppy@cerberus:~$

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, run jwl release.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/duckinator/jwl.

License

The gem is available as open source under the terms of the MIT License.