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Help Build Flarum

Interested in contributing to Flarum development? That's great! From opening a bug report to creating a pull request: every single one is appreciated and welcome. Flarum wouldn't be possible without our community contributions.

Before contributing, please read the code of conduct.

This document is a guide for developers who want to contribute code to Flarum. If you're just getting started, we recommend that you read the Getting Started documentation in the Extension docs to understand a bit more about how Flarum works.

Why Contribute to Flarum?

Have Real Impact. There are thousands of Flarum instances, with millions of aggregate end users. By contributing to Flarum, your code will have a positive impact on all of them.

🔮 Shape the Future of Flarum. We have a long backlog, and limited time. If you're willing to champion a feature or change, it's much more likely to happen, and you'll be able to enact your vision for it. Plus, our roadmap and milestones are set by our core development team, and all of us started as contributors. The best road to influence is contributing.

🧑‍💻 Become a Better Engineer. Our codebase is modern, and we heavily value good engineering and clean code. There's also a lot of interesting, challenging problems to solve regarding design, infrastructure, performance, and extensibility. Especially if you're a student or early in your career, working on Flarum is a great opportunity to build development skills.

🎠 It's Fun! We really enjoy working on Flarum: there's a lot of interesting challenges and fun features to build. We also have an active community on our forums and Discord server.

What to Work On

Check out our upcoming Milestones for an overview of what needs to be done. See the Good first issue label for a list of issues that should be relatively easy to get started with. If there's anything you're unsure of, don't hesitate to ask! All of us were just starting out once.

If you're planning to go ahead and work on something, please comment on the relevant issue or create a new one first. This way we can ensure that your precious work is not in vain.

Since Flarum is so extension-driven, we highly recommend our extension docs as a reference when working on core, as well as for bundled extensions. You should start with the introduction for a better understanding of our extension philosophy.

Development Setup

Setting Up a Local Codebase

flarum/flarum is a "skeleton" application which uses Composer to download the core package and a bunch of extensions. Source code for Flarum core, extensions, and all packages used by the aforementioned is located in the Flarum monorepo flarum/framework. In order to contribute to these, you'll need to fork and clone the monorepo repository locally, and then add it to your dev environment as a Composer path repository:

git clone
cd flarum

# Or, when you want to clone directly into the current directory
git clone .
# Note, the directory must be empty

# Set up a Composer path repository for Flarum monorepo packages
composer config repositories.0 path "PATH_TO_MONOREPO/*/*"
git clone<username>/framework.git PATH_TO_MONOREPO

Next, ensure that Composer accepts unstable releases from your local copies by setting the minimum-stability key to dev in composer.json.

Finally, run composer install to complete the installation from the path repositories.

After your local installation is set up, make sure you've enabled debug mode in config.php, and set display_errors to On in your php config. This will allow you to see error details for both Flarum and PHP. Debug mode also forces a re-compilation of Flarum's asset files on each request, removing the need to call php flarum cache:clear after each change to the extension's JavaScript or CSS.

Flarum's front-end code is written in ES6 and transpiled into JavaScript. During development you will need to recompile the JavaScript using Node.js and yarn. Please do not commit the resulting dist files when sending PRs; this is automatically taken care of when changes are merged into the main branch.

To contribute to the frontend, first install the JavaScript dependencies. The monorepo uses yarn workspaces to easily install JS dependencies across all packages within.

cd packages/framework
yarn install

Then you can watch JavaScript files for changes during development:

cd framework/core/js
yarn dev

The process is the same for extensions.

cd extensions/tags/js
yarn dev

Development Tools

After you've forked and cloned the repositories you'll be working on, you'll need to set up local hosting so you can test out your changes. Flarum doesn't currently come with a development server, so you'll need to set up Apache/NGINX/Caddy/etc to serve this local Flarum installation.

Alternatively, you can use tools like, Laravel Valet (Mac), XAMPP (Windows), or Docker-Flarum (Linux) to serve a local forum.

Most Flarum contributors develop with PHPStorm or Visual Studio Code.

Development Workflow

A typical contribution workflow looks like this:

  1. 🧭 Plan out your contribution

  2. 🌳 Branch off the appropriate branch into a new feature branch.

    • Bug fixes should be sent to the latest stable branch.
    • Minor features that are fully backwards compatible with the current Flarum release may be sent to the latest stable branch.
    • Major features should always be sent to the main branch, which contains the upcoming Flarum release.
    • Internally we use the naming scheme <initials>/<short-description> (eg. tz/refactor-frontend).
  3. 🔨 Write some code.

  4. 🚦 Test your code.

    • Add unit tests as necessary when fixing bugs or adding features.
    • Run the test suite with vendor/bin/phpunit in the relevant package folder.
    • See here for more information about testing in Flarum.
  5. 💾 Commit your code with a descriptive message.

    • If your change resolves an existing issue (usually, it should) include "Fixes #123" on a newline, where 123 is the issue number.
    • Follow the Conventional Commits specification.
    • Fix commits should describe the issue fixed, not how it was fixed.
  6. 🎁 Submit a Pull Request on GitHub.

    • Fill out the pull request template.
    • If your change is visual, include a screenshot or GIF demonstrating the change.
    • Do NOT check-in the JavaScript dist files. These will be compiled automatically on merge.
  7. 🤝 Engage with the Flarum team for approval.

    • Team members will review your code. We may suggest some changes or improvements or alternatives, but for small changes your pull request should be accepted quickly.
    • When addressing feedback, push additional commits instead of overwriting or squashing (we will squash on merge).
  8. 🕺 Dance like you just contributed to Flarum.

Coding Style

In order to keep the Flarum codebase clean and consistent, we have a number of coding style guidelines that we follow. When in doubt, read the source code.

Don't worry if your code styling isn't perfect! StyleCI and Prettier will automatically check formatting for every pull request. This allows us to focus on the content of the contribution, not the code style.


Flarum follows the PSR-2 coding standard and the PSR-4 autoloading standard. On top of this, we conform to a number of other style rules. We use PHP 7 type hinting and return type declarations where possible, and PHPDoc to provide inline documentation. Try and mimic the style used by the rest of the codebase in your contributions.

  • Namespaces should be singular (eg. Flarum\Discussion, not Flarum\Discussions)
  • Interfaces should be suffixed with Interface (eg. MailableInterface)
  • Abstract classes should be prefixed with Abstract (eg. AbstractModel)
  • Traits should be suffixed with Trait (eg. ScopeVisibilityTrait)


Flarum's JavaScript mostly follows the Airbnb Style Guide. We use ESDoc to provide inline documentation.


Columns should be named according to their data type:

  • DATETIME or TIMESTAMP: {verbed}_at (eg. created_at, read_at) or {verbed}_until (eg. suspended_until)
  • INT that is a count: {noun}_count (eg. comment_count, word_count)
  • Foreign key: {verbed}_{entity}_id (eg. hidden_user_id)
    • Verb can be omitted for primary relationship (eg. post author is just user_id)
  • BOOL: is_{adjective} (eg. is_locked)

Tables should be named as follows:

  • Use plural form (discussions)
  • Separate multiple words with underscores (access_tokens)
  • For relationships tables, join the two table names in singular form with an underscore in alphabetical order (eg. discussion_user)


Flarum's CSS classes roughly follow the SUIT CSS naming conventions using the format .ComponentName-descendentName--modifierName.


We use a standard key format to name translation keys descriptively and consistently.

Contributor License Agreement

By contributing your code to Flarum you grant the Flarum Foundation (Stichting Flarum) a non-exclusive, irrevocable, worldwide, royalty-free, sublicensable, transferable license under all of Your relevant intellectual property rights (including copyright, patent, and any other rights), to use, copy, prepare derivative works of, distribute and publicly perform and display the Contributions on any licensing terms, including without limitation: (a) open source licenses like the MIT license; and (b) binary, proprietary, or commercial licenses. Except for the licenses granted herein, You reserve all right, title, and interest in and to the Contribution.

You confirm that you are able to grant us these rights. You represent that You are legally entitled to grant the above license. If Your employer has rights to intellectual property that You create, You represent that You have received permission to make the Contributions on behalf of that employer, or that Your employer has waived such rights for the Contributions.

You represent that the Contributions are Your original works of authorship, and to Your knowledge, no other person claims, or has the right to claim, any right in any invention or patent related to the Contributions. You also represent that You are not legally obligated, whether by entering into an agreement or otherwise, in any way that conflicts with the terms of this license.