Contributing to Alloy

🎈 Thanks for your help improving the project! We are so happy to have you!

There are opportunities to contribute to Alloy at any level. It doesn't matter if you are just getting started with Rust or are the most weathered expert, we can use your help.

No contribution is too small and all contributions are valued.

This guide will help you get started. Do not let this guide intimidate you. It should be considered a map to help you navigate the process.

The dev channel is available for any concerns not covered in this guide, please join us!

Conduct

The Alloy project adheres to the Rust Code of Conduct. This describes the minimum behavior expected from all contributors. Instances of violations of the Code of Conduct can be reported by contacting the project team at james@prestwich.

Contributing in Issues

For any issue, there are fundamentally three ways an individual can contribute:

  1. By opening the issue for discussion: For instance, if you believe that you have uncovered a bug in Alloy, creating a new issue in the Alloy issue tracker is the way to report it.

  2. By helping to triage the issue: This can be done by providing supporting details (a test case that demonstrates a bug), providing suggestions on how to address the issue, or ensuring that the issue is tagged correctly.

  3. By helping to resolve the issue: Typically this is done either in the form of demonstrating that the issue reported is not a problem after all, or more often, by opening a Pull Request that changes some bit of something in Alloy in a concrete and reviewable manner.

Anybody can participate in any stage of contribution. We urge you to participate in the discussion around bugs and participate in reviewing PRs.

At this time, we will not be accepting contributions that only fix spelling or grammatical errors in documentation, code or elsewhere.

Asking for General Help

If you have reviewed existing documentation and still have questions or are having problems, you can open an issue asking for help.

In exchange for receiving help, we ask that you contribute back a documentation PR that helps others avoid the problems that you encountered.

Pull Requests

Pull Requests are the way concrete changes are made to the code, documentation, and dependencies in the Alloy repository.

Before making a large change, it is usually a good idea to first open an issue describing the change to solicit feedback and guidance. This will increase the likelihood of the PR getting merged.

When opening a PR please select the "Allow Edits From Maintainers" option. Alloy maintains strict standards for code quality and style, as well as commit signing. This option allows us to make small changes to your PR to bring it in line with these standards. It helps us get your PR in faster, and with less work from you.

Commits

It is a recommended best practice to keep your changes as logically grouped as possible within individual commits. There is no limit to the number of commits any single Pull Request may have, and many contributors find it easier to review changes that are split across multiple commits.

That said, if you have a number of commits that are "checkpoints" and don't represent a single logical change, please squash those together.

Note that multiple commits often get squashed when they are landed (see the notes about commit squashing).

Commit message guidelines

Commit messages should follow the Conventional Commits specification.

Usage

This section lists some commonly needed commands.

First create a fork.

Next clone your fork with the --recurse-submodules flag:

git clone --recurse-submodules $FORK_URL

The book is build with mdbook, which you can get by running cargo install mdbook.

The book requires mdbook-external-links: cargo install mdbook-external-links and mdbook-linkcheck: cargo install mdbook-linkcheck.

To see the book change live run:

mdbook serve

To run the book with docker, run:

docker run -p 3000:3000 -v `pwd`:/book peaceiris/mdbook serve

To perform an update of generated output inspect and run ./scripts/update.sh.

To add a new section (file) to the book, add it to ./src/SUMMARY.md.

Discuss and update

You will probably get feedback or requests for changes to your Pull Request. This is a big part of the submission process so don't be discouraged! Some contributors may sign off on the Pull Request right away, others may have more detailed comments or feedback. This is a necessary part of the process in order to evaluate whether the changes are correct and necessary.

Any community member can review a PR and you might get conflicting feedback. Keep an eye out for comments from code owners to provide guidance on conflicting feedback.

Once the PR is open, do not rebase the commits. See Commit Squashing for more details.

Commit Squashing

In most cases, do not squash commits that you add to your Pull Request during the review process. When the commits in your Pull Request land, they may be squashed into one commit per logical change. Metadata will be added to the commit message (including links to the Pull Request, links to relevant issues, and the names of the reviewers). The commit history of your Pull Request, however, will stay intact on the Pull Request page.

Reviewing Pull Requests

Any Alloy community member is welcome to review any pull request.

All Alloy contributors who choose to review and provide feedback on Pull Requests have a responsibility to both the project and the individual making the contribution. Reviews and feedback must be helpful, insightful, and geared towards improving the contribution as opposed to simply blocking it. If there are reasons why you feel the PR should not land, explain what those are. Do not expect to be able to block a Pull Request from advancing simply because you say "No" without giving an explanation. Be open to having your mind changed. Be open to working with the contributor to make the Pull Request better.

Reviews that are dismissive or disrespectful of the contributor or any other reviewers are strictly counter to the Code of Conduct.

When reviewing a Pull Request, the primary goals are for the codebase to improve and for the person submitting the request to succeed. Even if a Pull Request does not land, the submitters should come away from the experience feeling like their effort was not wasted or unappreciated. Every Pull Request from a new contributor is an opportunity to grow the community.

Review a bit at a time.

Do not overwhelm new contributors.

It is tempting to micro-optimize and make everything about relative performance, perfect grammar, or exact style matches. Do not succumb to that temptation.

Focus first on the most significant aspects of the change:

  1. Does this change make sense for Alloy?
  2. Does this change make Alloy better, even if only incrementally?
  3. Are there clear bugs or larger scale issues that need attending to?
  4. Is the commit message readable and correct? If it contains a breaking change is it clear enough?

Note that only incremental improvement is needed to land a PR. This means that the PR does not need to be perfect, only better than the status quo. Follow up PRs may be opened to continue iterating.

When changes are necessary, request them, do not demand them, and do not assume that the submitter already knows how to add a test or run a benchmark.

Specific performance optimization techniques, coding styles and conventions change over time. The first impression you give to a new contributor never does.

Nits (requests for small changes that are not essential) are fine, but try to avoid stalling the Pull Request. Most nits can typically be fixed by the Alloy Collaborator landing the Pull Request but they can also be an opportunity for the contributor to learn a bit more about the project.

It is always good to clearly indicate nits when you comment: e.g. Nit: change foo() to bar(). But this is not blocking.

If your comments were addressed but were not folded automatically after new commits or if they proved to be mistaken, please, hide them with the appropriate reason to keep the conversation flow concise and relevant.

Be aware of the person behind the code

Be aware that how you communicate requests and reviews in your feedback can have a significant impact on the success of the Pull Request. Yes, we may land a particular change that makes Alloy better, but the individual might just not want to have anything to do with Alloy ever again. The goal is not just having good code.

Abandoned or Stalled Pull Requests

If a Pull Request appears to be abandoned or stalled, it is polite to first check with the contributor to see if they intend to continue the work before checking if they would mind if you took it over (especially if it just has nits left). When doing so, it is courteous to give the original contributor credit for the work they started (either by preserving their name and email address in the commit log, or by using an Author: meta-data tag in the commit.

Adapted from the Tokio contributing guide.