FOS-0027Cal.comproject managementmore toolsSponsored (free) access to Cal.com's paid team offering for open source projects (applicants provide…ACTIVEverified 2026-09-07›
What you get
Sponsored (free) access to Cal.com's paid team offering for open source projects (applicants provide their Cal.com team slug); exact plan tier is not specified on the page. In exchange the project must display a "Book us with Cal.com" banner in its footer and README with UTM-tagged links.
Applies to
the project , not individual maintainers
Requirements
no stated requirements
How to apply
Email peer@cal.com with project description, confirmation of criteria, why the free tier is insufficient, your Cal.com team slug, and a link to the repository.
Provenance
Confirmed against cal.com/help/event-types/sponsor on 2026-09-07, matched anchor “Can Cal.com sponsor my open source project”.
FOS-0075Fiberyproject managementdocumentationFibery is 100% free for all open-source projects (full product at no cost, not a discount)…ACTIVEverified 2026-09-07›
What you get
Fibery is 100% free for all open-source projects (full product at no cost, not a discount). Fibery also offers a separate 50% permanent discount for educational and nonprofit organizations.
Applies to
the project , not individual maintainers
Requirements
no stated requirements
How to apply
Submit the application form for open-source projects linked from the special-pricing page ("just let us know").
Provenance
Confirmed against fibery.com/blog/product-updates/fibery-special-pricing on 2026-09-07, matched anchor “Open source companies support”.
Offer 1, All Products Pack (OSS development licenses)
What you get
Free licenses for the full JetBrains product lineup (IntelliJ IDEA Ultimate, PyCharm, WebStorm, etc.) for a project's core contributors, for use on the open source project.
Application form on the offer page; project lead applies on behalf of contributors.
Provenance
Confirmed against jetbrains.com/community/opensource on 2026-09-07, matched anchor “licenses for open source development”.
Offer 2, TeamCity (Open Source license)
What you get
Free TeamCity Professional Server open source license: unlimited servers with up to 100 build configurations per server and 3 build agents per server at no cost, with free upgrades during the license term.
Applies to
the project , not individual maintainers
Requirements
OSI-approved licensenon-commercial / non-profit
run a repo match above to see which you meet →
How to apply
Request via the JetBrains open source program page (team tool licenses, including TeamCity, are requested alongside All Products Pack subscriptions).
Provenance
Confirmed against jetbrains.com/community/opensource on 2026-09-07, matched anchor “licenses for open source development”.
Offer 3, YouTrack (OSS team license)
What you get
Free YouTrack issue tracking license for the open source team, requested through the JetBrains open source program (program covers team tools including YouTrack and TeamCity).