head to head · open source
OpenAPI-Specification vs optillm
OpenAPI-Specification has 31,297 GitHub stars, 9,144 forks, 80 open issues and last shipped 2 days ago. optillm has 4,337 stars, 398 forks, 23 open issues and last shipped 3 days ago. OpenAPI-Specification leads on adoption by 622% (31,297 vs 4,337 stars). OpenAPI-Specification is written in Markdown under Apache-2.0; optillm is written in Python under Apache-2.0. OpenAPI-Specification has attracted 29% as many forks as stars, optillm 9%. OpenAPI-Specification was the more recently maintained of the two, and both are self-hostable with no licence fee.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| OpenAPI-Specification | optillm | |
|---|---|---|
| GitHub stars | ★ 31K | ★ 4.3K |
| License | Apache-2.0 | Apache-2.0 |
| Written in | Markdown | Python |
| Last push | 2026-11-03 | 2026-11-02 |
| Forks | ⑂ 9.1K | ⑂ 398 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick OpenAPI-Specification if
- You weight community size — 31K stars and counting
- You want the Apache-2.0 license terms
- Your stack matches Markdown
- You value the larger contributor base for long-term maintenance
pick optillm if
- You want the optillm feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches Python
- You evaluated both and optillm fits your workflow better
About OpenAPI-Specification
The OpenAPI Specification The OpenAPI Specification is a community driven open specification within the OpenAPI Initiative, a Linux Foundation Collaborative Project. The OpenAPI Specification (OAS) defines a standard, programming language agnostic interface description for HTTP APIs. This allows both humans and computers to discover and understand the capabilities of a service without requiring access to source code, additional documentation, or inspection of network traffic. When properly defined via OpenAPI, a consumer can understand and interact with the remote service with a minimal amount of implementation…
read the full OpenAPI-Specification overview →
About optillm
OptiLLM 🚀 2 10x accuracy improvements on reasoning tasks with zero training 🤗 HuggingFace Space • 📓 Colab Demo • 💬 Discussions OptiLLM is an OpenAI API compatible optimizing inference proxy that implements 20+ state of the art techniques to dramatically improve LLM accuracy and performance on reasoning tasks without requiring any model training or fine tuning. It is possible to beat the frontier models using these techniques across diverse tasks by doing additional compute at inference time. A good example of how to combine such techniques together is the CePO approach from Cerebras. ✨ Key Features 🎯…
read the full optillm overview →
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Frequently asked questions
Is OpenAPI-Specification or optillm more popular?
OpenAPI-Specification has 31,297 GitHub stars and optillm has 4,337. OpenAPI-Specification has the larger community by that measure.
Are OpenAPI-Specification and optillm free?
Both are open source. OpenAPI-Specification is licensed under Apache-2.0 and optillm under Apache-2.0. Neither carries a licence fee.
What is the difference between OpenAPI-Specification and optillm?
OpenAPI-Specification is written in Markdown and optillm in Python. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, OpenAPI-Specification or optillm?
Choose OpenAPI-Specification if you want the larger community (31,297 stars) or its Apache-2.0 licence terms. Choose optillm if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.