Google Summer of Code (GSoC)
253 organisations took part between 2024 and 2026. 200 have repositories measured so far, last updated 11 Oct 2026.
The ranking rule. Share of pull requests from outside the core team that got a reply from a person within 7 days, across all of the organisation's measured repositories. Ties go to the higher outside merge rate. An organisation needs at least 20 outside pull requests to take a place; smaller ones follow, unranked.
Each year Google funds new contributors to spend about 12 weeks building something for an open source project.
You work with a mentor from the organisation you applied to. You do not need to be a student, only new to open source and 18 or older.
You write a proposal to one of the organisations below. That is why it matters which of them reply to newcomers.
Details and dates are on the official Google Summer of Code site.
Now is the best time to start: contribute small fixes to the organisation you want, so the mentors know your name before applications open.
Oct
You are here.
Organisations
213 organisations measured on GitHub
The free & open software radio ecosystem
GSoC 2024, 2025, 2026 · 12 repositories measured
pythonc++qtsimd
40 organisations cannot be measured on GitHub. They host their code elsewhere, or they are umbrella organisations whose projects change every year. They are listed so the ranking does not pretend they do not exist.
Mid January
Many publish their idea lists now.
Late February
Pick two or three and read their ideas.
Applications
Mid March
Send mentors a draft early for feedback.
End of March
About two weeks after opening.
End of April
Meet your mentor before coding starts.
Coding
Late May
About 12 paid weeks, midterm in July.
Late August
Larger projects can run into November.
Google has not published the 2027 dates yet; these follow the 2026 programme, which has kept the same shape for years. Official timeline
Start with gnuradio/gnuradio4-core
Web framework for perfectionists with deadlines
GSoC 2024, 2025, 2026 · 12 repositories measured
pythondjango
Start with django/djangoproject.com
An OS for servers to embedded devices
GSoC 2024, 2025, 2026 · 12 repositories measured
cllvmassemblymakeposix shell
Start with freebsd/poudriere
Genome analysis for all species
GSoC 2024, 2025 · 12 repositories measured
pythonmachine learningnatural language processingnextflowcloud storage
Start with sanger-tol/readmapping
Building the future of Event-Driven Architectures
GSoC 2024, 2025 · 12 repositories measured
javascriptjavagotypescriptraml
Start with asyncapi/website
Our eyes on the ocean, coasts, and Great Lakes
GSoC 2024, 2025, 2026 · 12 repositories measured
pythonjavarzarrnetcdf
Start with ioos/ioos_qc
Fast,Scalable,Distributed revision control system
GSoC 2024, 2025, 2026 · 4 repositories measured
shell scriptgitc language
Start with git/git.github.io
TV, Rust, Flutter, Linux, VR and C. In any order.
GSoC 2024, 2025, 2026 · 7 repositories measured
clinuxrustflutter
Start with CCExtractor/sample-platform
3D Medical visualization and neuronavigation tool
GSoC 2024, 2025, 2026 · 1 repository measured
pythoncythonnumpydicomvtk
Start with invesalius/invesalius3
Unit, API test generation agent using AI & EBPF
GSoC 2024, 2025 · 12 repositories measured
pythongolangnodeaimern
Start with keploy/keploy
Dates for the next round are published by Google on the official timeline. Contributable is independent and not affiliated with Google.