Retro Funding: Dev Tooling
Retroactively rewards already-launched toolchain software (compilers, libraries, debuggers) used by Superchain builders, measured by an algorithm rather than by proposal.
What you get
Can you apply
My project is Open Source. My project has a public GitHub repo with a history of commits. I am able to verify ownership over my project by adding a file to the root of the GitHub repo. My project has JavaScript and/or Rust packages published on relevant registries (e.g, npm or crates.io) with their associated GitHub repo verified in OP Atlas (Optional)
When
Retroactive: this rewards work you have already shipped rather than a proposal, so there is nothing to apply for up front.
What Optimism funds
Rewards impact after the fact: Retro Funding pays OP to projects that have already shipped and can prove their contribution to Optimism and the wider Superchain. The Collective has allocated 850M OP to Retro Funding and has rewarded 60,815,042 OP to contributors since 2022. A smaller forward-looking Growth Grants track funds growth plans from apps that have already launched.
Everything Optimism funds →Details
"This program is for software projects that have already launched and can prove their impact." Impact is measured on adoption of the tool by onchain builders, the tool's importance in onchain application development, and features supporting Superchain interop, "via an evaluation algorithm powered by GitHub, npm, Crates, and Onchain data". Season timeline as published: Jul 31 - Dec 24, 2025, with monthly application deadlines and monthly rewards streamed via Superfluid. "Any projects enrolled in the previous season of Retro Funding will automatically roll over to this season." The mission page showed status Closed at time of capture. Published example rewards: Solidity 356K OP, Solady 167K OP, Scaffold-ETH 2 136K OP, DefiLlama 137K OP, Revm 97.3K OP.