We’re applying to Google Summer of Code again this year! While accepted organizations are not yet announced – they will be on February 19th (check the gsoc timeline here), we’re already collecting project ideas.
You can review and discuss ideas listed on our Swift Project Ideas Page for 2026, and you can also come up with your own ideas. If you want to discuss those, please start threads on the forums in the GSoC category and tag them with the gsoc2026tag!
If and when the Swift project will be accepted by GSoC to participate this year again, we’ll post here again so keep your eyes peeled!
I wonder if this is something we might still want.(from gsoc 2025 idea list)
Refactor sourcekitd to use Swift Concurrency
Project size: 175 hours (medium)
Estimated difficulty: Intermediate
Recommended skills
Proficiency in Swift, including Swift 6’s concurrency model
Basic proficiency in C++
Description
sourcekitd is implemented in the Swift compiler’s repository to use the compiler’s understanding of Swift code to provide semantic functionality. It is currently implemented in C++. By refactoring its request handling and AST manager to Swift, we can take advantage of Swift’s concurrency safety, improving its data race safety, making it easier to reason about and maintain.
On macOS, sourcekitd is run as an XPC service, while on all other platforms, sourcekitd is run in the sourcekit-lsp process. As a stretch goal, refactoring the request handling would allow us to run sourcekitd in a separate process on Linux and Windows as well improving SourceKit-LSP’s resilience as crashes inside sourcekitd would not cause a crash of the LSP process itself.
Expected outcomes/benefits/deliverables
Improved concurrency-safety of sourcekitd and better maintainability.
I personally won’t be mentoring during GSoC this year and speaking to my coworkers there seems to be less interest on somebody else mentoring the project in general this year. That being said, GSoC is always about students proposing projects (we just publish a list of proposal ideas), so if you think this is a great project that you’d excel at, I would still encourage you to propose it.
That is true, however please start a thread on the forums before just submitting a proposal and make an effort to find a mentor through the forums. We are very unlikely to accept a proposal that did not have prior discussions with some mentor before submitting a proposal.