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Contributing to Tremor

Thank you for your interest in contributing to the Tremor project! There are many ways to contribute, and we appreciate all of them. Here's links to the primary ways to contribute to the Tremor project as an external contributor:

If you have questions, please make a query hop on over to Tremor Chat.

As a reminder, all contributors are expected to follow our Code of Conduct.

If this is your first time contributing, we would like to thank you for spending time on the project! Please reach out directly to any core project member if you would like any guidance or assistance.

Feature Requests

To request a change to the way that Tremor works, please head over to the RFCs repository and view the README for instructions.

Bug Reports

While bugs are unfortunate, they're a reality in software. We can't fix what we don't know about, so please report liberally. If you're not sure if something is a bug or not, feel free to file a bug anyway.

If you believe reporting your bug publicly represents a security risk to Tremor users, please follow our instructions for reporting security vulnerabilities.

If you have the chance, before reporting a bug, please search existing issues, as it's possible that someone else has already reported your error. This doesn't always work, and sometimes it's hard to know what to search for, so consider this extra credit. We won't mind if you accidentally file a duplicate report.

Similarly, to help others who encountered the bug find your issue, consider filing an issue with a descriptive title, which contains information that might be unique to it. This can be the language or compiler feature used, the conditions that trigger the bug, or part of the error message if there is any. An example could be: "impossible case reached" on match expression in tremor scripting language.

To open an issue is as follow this link and filling out the fields. Here's a template that you can use to file a bug, though it's not necessary to use it exactly:

    <short summary of the bug>

    I tried this code:

    <code sample that causes the bug>

    I expected to see this happen: <explanation>

    Instead, this happened: <explanation>

    ## Meta

    `tremor-script --version`:


All three components are important: what you did, what you expected, what happened instead. Please include the output of tremor --version, which includes important information about what platform you're on, what version of Rust you're using, etc.

Sometimes, a backtrace is helpful, and so including that is nice. To get a backtrace, set the RUST_BACKTRACE environment variable to a value other than 0. The easiest way to do this is to invoke tremor like this:

$ RUST_BACKTRACE=1 tremor...

The Build System

For info on how to configure and build the project, please see the tremor build guide. This guide contains info for contributions to the project and the standard facilities. It also lists some really useful commands to the build system, which could save you a lot of time.

Pull Requests

Pull requests are the primary mechanism we use to change Tremor. GitHub itself has some great documentation on using the Pull Request feature. We use the "fork and pull" model described here, where contributors push changes to their personal fork and create pull requests to bring those changes into the source repository.

Please make pull requests against the main branch.

Tremor follows a no merge policy, meaning, when you encounter merge conflicts you are expected to always rebase instead of merge. E.g. always use rebase when bringing the latest changes from the main branch to your feature branch. Also, please make sure that fixup commits are squashed into other related commits with meaningful commit messages.

GitHub allows closing issues using keywords. This feature should be used to keep the issue tracker tidy. However, it is generally preferred to put the "closes #123" text in the PR description rather than the issue commit; particularly during rebasing, citing the issue number in the commit can "spam" the issue in question.

All pull requests are reviewed by another person.

If you want to request that a specific person reviews your pull request, you can add an r? to the pull request description. For example, Darach Ennis usually reviews documentation changes. So if you were to make a documentation change, add

r? @darach

to the end of the pull request description. This is entirely optional.

After someone has reviewed your pull request, they will leave an annotation on the pull request with an r+. It will look something like this:


Once your merge request is approved it will enter the merge queue

Speaking of tests, Rust has a comprehensive test suite. More information about it can be found [here][].

External Dependencies

Currently building the Tremor project will also build the following external projects:

Breakage is not allowed in released branches and must be addressed before a PR is merged.

Writing Documentation

Documentation improvements are very welcome. The source of is located in the tremor docs repo. Documentation pull requests function in the same way as other pull requests.

To find documentation-related issues, sort by the doc label.

Additionally, contributions to the [tremor-guide] are always welcome. Contributions can be made directly here repo. The issue tracker in that repo is also a great way to find things that need doing.

Issue Triage

Sometimes, an issue will stay open, even though the bug has been fixed. And sometimes, the original bug may go stale because something has changed in the meantime.

It can be helpful to go through older bug reports and make sure that they are still valid. Load up an older issue, double check that it's still true, and leave a comment letting us know if it is or is not. The least recently updated sort is good for finding issues like this.

Out-of-tree Contributions

There are a number of other ways to contribute to Tremor that don't deal with this repository.

Answer questions in the Get Help! channels from the Tremor Chat.

Participate in the RFC process.

Tremor Chat

Join the tremor community discord