Page MenuHomeIsabelle/Phabricator

Contributing Bug Reports
Phabricator Contributor Documentation (Contributing in Detail)

Describes how to file an effective Phabricator bug report.

Level Requirements

We accept bug reports through two channels: paid support and community support.

If you are a paying customer, use the Support Channel for your account to report bugs. This document may help you file reports which we can resolve more quickly, but you do not need to read it or follow the guidelines.

Other users can follow the guidelines in this document to file bug reports on the community forum.


This article describes how to file an effective Phabricator bug report.

The most important things to do are:

  • check the list of common fixes below;
  • make sure Phabricator is up to date;
  • make sure we support your setup;
  • gather debugging information; and
  • explain how to reproduce the issue.

The rest of this article walks through these points in detail.

For general information on contributing to Phabricator, see Contributor Introduction.

Common Fixes

Before you file a report, here are some common solutions to problems:

  • Update Phabricator: We receive a lot of bug reports about issues we have already fixed in HEAD. Updating often resolves issues. It is common for issues to be fixed in less than 24 hours, so even if you've updated recently you should update again. If you aren't sure how to update, see the next section.
  • Update Libraries: Make sure libphutil/, arcanist/ and phabricator/ are all up to date. Users often update phabricator/ but forget to update arcanist/ or libphutil/. When you update, make sure you update all three libraries.
  • Restart Apache or PHP-FPM: Phabricator uses caches which don't get reset until you restart Apache or PHP-FPM. After updating, make sure you restart.

Update Phabricator

Before filing a bug, make sure you are up to date. We receive many bug reports for issues we have already fixed, and even if we haven't fixed an issue we'll be able to resolve it more easily if you file a report based on HEAD. (For example, an old stack trace may not have the right line numbers, which will make it more difficult for us to figure out what's going wrong.)

To update Phabricator, use a script like the one described in Upgrading Phabricator.

If you can not update for some reason, please include the version of Phabricator you are running when you file a report.

For help, see Providing Version Information.

Supported Issues

Before filing a bug, make sure you're filing an issue against something we support.

We can NOT help you with issues we can not reproduce. It is critical that you explain how to reproduce the issue when filing a report.

For help, see Providing Reproduction Steps.

We do NOT support prototype applications. If you're running into an issue with a prototype application, you're on your own. For more information about prototype applications, see User Guide: Prototype Applications.

We do NOT support third-party packages or instructions. If you installed Phabricator (or configured some aspect of it) using a third-party package or by following a third-party guide (like a blog post), we can not help you. Phabricator changes quickly and third-party information is unreliable and often falls out of date. Contact the maintainer of the package or guide you used, or reinstall following the upstream instructions.

We do NOT support custom code development or third-party libraries. If you're writing an extension, you're on your own. We provide some documentation, but can not help you with extension or library development. If you downloaded a library from somewhere, contact the library maintainer.

We do NOT support bizarre environments. If your issue is specific to an unusual installation environment, we generally will not help you find a workaround. Install Phabricator in a normal environment instead. Examples of unusual environments are shared hosts, nontraditional hosts (gaming consoles, storage appliances), and hosts with unusually tight resource constraints. The vast majority of users run Phabricator in normal environments (modern computers with root access) and these are the only environments we support.

Otherwise, if you're having an issue with a supported first-party application and followed the upstream install instructions on a normal computer, we're happy to try to help.

Getting More Information

For some issues, there are places you can check for more information. This may help you resolve the issue yourself. Even if it doesn't, this information can help us figure out and resolve an issue.

  • For issues with arc or any other command-line script, you can get more details about what the script is doing by adding the --trace flag.
  • For issues with Phabricator, check your webserver error logs.
    • For Apache, this is often /var/log/httpd/error.log, or /var/log/apache2/error.log or similar.
    • For nginx, check both the nginx and php-fpm logs.
  • For issues with the UI, check the Javascript error console in your web browser.
  • Some other things, like daemons, have their own debug flags or troubleshooting steps. Check the documentation for information on troubleshooting. Adjusting settings or enabling debugging modes may give you more information about the issue.


The most important part of your report content is instructions on how to reproduce the issue. What did you do? If you do it again, does it still break? Does it depend on a specific browser? Can you reproduce the issue on a test instance on

It is nearly impossible for us to resolve many issues if we can not reproduce them. We will not accept reports which do not contain the information required to reproduce problems.

For help, see Providing Reproduction Steps.

File a Bug Report

If you're up to date, have collected information about the problem, and have the best reproduction instructions you can come up with, you're ready to file a report.

It is particularly critical that you include reproduction steps.

You can file a report on the community forum, here:

Next Steps

Continue by: