Alternatives

Products that do what Rubberduck – Open Source Tool to Emulate OpenAI/Anthropic APIs Locally does

1. 1
   OpenAI Universe▲329

   Platform for measuring and training AI agents

   2016

2. 2VA
   Vector: a Matrix-powered open-source collaboration Web/Android/iOS app▲186

   2016 · vector.im

3. 3SA
   Stargate – An open source API framework for data▲72

   2020 · stargate.io

4. 4AS
   AI-SDK-Cpp – Unified C++ SDK for OpenAI, Anthropic, and More▲5

   2025 · github.com

5. 5AO
   An Open Source Version of OpenAI Assistants API▲5

   2023 · twitter.com

6. 6SN
   Surf.new – An open-source alternative to OpenAI Operator▲9

   2025 · surf.new

7. 7AA
   AI Artifacts - open-source template of Anthropic's Artifacts UI▲7

   2024 · github.com

8. 8AA
   Agyn, an open-source Kubernetes runtime for AI agents▲9

   May 2026 · github.com

9. 9SN
   Surf.new – An open-source alternative to OpenAI Operator▲7

   2025 · github.com

10. 10CA
    Cloudsnap, an integration platform for developers▲18

    2012 · cloudsnap.com

11. 11OS
    Open-Source Desktop AI Webscraper▲9

    2023 · github.com

12. 12CC
    CodeSpin - Code generation framework and tools using OpenAI APIs▲7

    2023 · github.com

13. 13CA
    Cloudbank-An OpenAI universe Alternative▲9

    2018 · github.com

14. 14UP
    Unified Python SDK for Multimodal AI (OpenAI, ElevenLabs, Flux, Ollama)▲5

    Jan 2026 · github.com

15. 15GF
    Grunden – Frontier AI inference hosted in Sweden, OpenAI-compatible▲7

    May 2026 · grunden.ai

16. 16OS
    Open source AI data analyst locally using CLI▲7

    2024 · github.com

17. 17SM
    Second Me – An Open-Source Alternative to Centralized AI▲7

    2025 · github.com

18. 18BO
    Bashi – open-source and extensible AI assistant platform and app▲9

    2023 · github.com

19. 19OS
    Open-Source Infrastructure for AI Code Interpreters▲6

    2024 · e2b.dev

20. 20OS
    Open-Source Roadmap App▲6

    2023 · github.com

21. 21HO
    Hoppscotch – Open-Source API development ecosystem▲6

    2021 · hoppscotch.io

22. 22OS
    Open-Source Web/API Monitoring Tool▲7

    2021 · github.com

23. 23OC
    OpenAI Codex for Free with GitHub Models▲7

    2025 · gist.github.com

24. 24IA
    Illa.ai – Open-Source AI Agent and AI Native App Community▲6

    2023 · illa.ai

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