Issue Tracker

Cargo’s issue tracker is located at This is the primary spot where we track bugs and small feature requests. See Process for more about our process for proposing changes.

Filing issues

We can’t fix what we don’t know about, so please report problems liberally. This includes problems with understanding the documentation, unhelpful error messages, and unexpected behavior.

If you think that you have identified an issue with Cargo that might compromise its users’ security, please do not open a public issue on GitHub. Instead, we ask you to refer to Rust’s security policy.

Opening an issue is as easy as following this link. There are several templates for different issue kinds, but if none of them fit your issue, don’t hesitate to modify one of the templates, or click the Open a blank issue link.

The Rust tools are spread across multiple repositories in the Rust organization. It may not always be clear where to file an issue. No worries! If you file in the wrong tracker, someone will either transfer it to the correct one or ask you to move it. Some other repositories that may be relevant are:

Issues with cargo fix can be tricky to know where they should be filed, since the fixes are driven by rustc, processed by rustfix, and the front-interface is implemented in Cargo. Feel free to file in the Cargo issue tracker, and it will get moved to one of the other issue trackers if necessary.

Issue labels

Issue labels are very helpful to identify the types of issues and which category they are related to. The Cargo team typically manages assigning labels. The labels use a naming convention with short prefixes and colors to indicate the kind of label:

  • Yellow, A-prefixed labels state which area of the project an issue relates to.

  • Light purple, C-prefixed labels represent the category of an issue. In particular, C-feature-request marks proposals for new features. If an issue is C-feature-request, but is not Feature accepted or I-nominated, then it was not thoroughly discussed, and might need some additional design or perhaps should be implemented as an external subcommand first. Ping @rust-lang/cargo if you want to send a PR for such issue.

  • Dark purple, Command-prefixed labels mean the issue has to do with a specific cargo command.

  • Green, E-prefixed labels indicate the level of experience or effort necessary to fix the issue. E-mentor issues also have some instructions on how to get started. Generally, all of the E-prefixed labels are issues that are ready for someone to contribute to!

  • Red, I-prefixed labels indicate the importance of the issue. The I-nominated label indicates that an issue has been nominated for prioritizing at the next triage meeting.

  • Purple gray, O-prefixed labels are the operating system or platform that this issue is specific to.

  • Orange, P-prefixed labels indicate a bug’s priority.

  • S-prefixed labels are “status” labels, typically used for PRs, but can also indicate an issue is S-blocked.

  • The light orange relnotes label marks issues that should be highlighted in the Rust release notes of the next release.

  • Dark blue, Z-prefixed labels are for unstable, nightly features.