Clarification regarding community contributions and pending PRs

[Borda]

Hello @FabianIsensee,

First of all, thank you for developing and maintaining nnUNet. It is an incredibly valuable tool that is heavily relied upon by the community, and we really appreciate all the hard work that goes into it.

I am opening this issue to politely ask for some clarification regarding the project's current stance on community contributions. Looking through the open Pull Requests, I noticed that there are quite a few community-submitted PRs that have been hanging for several months without review or activity. In some cases, maintainers have assigned themselves to these PRs, but no further action has been taken.

At the same time, it looks like maintainers are still actively pushing and merging their own PRs. This suggests the project is very much alive, but perhaps the workflow or priorities for handling external contributions have changed.

Could you clarify if external contributions are still welcome and being reviewed?

• If the team currently lacks the time or bandwidth to review community PRs, that is completely understandable! However, it would be very helpful to clearly state this in the README.md or CONTRIBUTING.md.
• If certain types of PRs are no longer being accepted, closing the pending ones or adding a quick note would help manage expectations and save contributors from spending time on code that won't be merged.

Thank you again for your time and dedication to this project! Looking forward to hearing your thoughts.

[FabianIsensee]

Dear @Borda ,
thank you for the kind words and for raising this point in such a constructive way. We are very aware of the value nnU-Net has for the community, and we are happy to invest time into continuously improving and maintaining it.

As you suspected, we are currently extremely bandwidth limited. We are a research department without dedicated staff or funding for maintaining nnU-Net. Our primary focus is research, and everyone working on the repository does so alongside their other responsibilities, often at the expense of other projects or thesis work. Because of this, we have to focus on the most pressing issues and unfortunately deprioritize many other tasks. nnU-Net is free for everyone to use, and while many companies rely on it in commercial settings, we do not receive financial support for maintaining it. We therefore kindly ask that expectations are adjusted accordingly, especially regarding our ability to respond to questions in the issues.

That said, I agree that pull requests deserve particular attention. A PR usually represents a significant amount of work that someone invested with the intention of contributing improvements back to the community. Reviewing PRs is something I need to take care of personally. Until recently I was leading my own team within the division, which limited how much time I could justify allocating to nnU-Net. That situation is changing now, and I will make sure to prioritize reviewing community PRs more going forward.

Regarding contribution guidelines, I also think your suggestion to add a dedicated CONTRIBUTING or README section is very valuable. Clear guidance on what types of contributions are most helpful, and what contributors should expect from the review process, will help reduce frustration and avoid unnecessary work. I will draft a contribution policy in the coming days and add it to the repository.
Best,
Fabian