head to head · open source
utopia vs simba
utopia has 8,667 GitHub stars, 1,185 forks, 27 open issues and last shipped yesterday. simba has 1,547 stars, 116 forks, 6 open issues and last shipped 5 months ago. utopia leads on adoption by 460% (8,667 vs 1,547 stars). utopia is written in Rust under Apache-2.0; simba is written in TypeScript under Apache-2.0. utopia has attracted 14% as many forks as stars, simba 7%. utopia was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 3 topic tags (knowledge-base, llm, rag), so they are genuine substitutes rather than adjacent tools.
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
| utopia | simba | |
|---|---|---|
| GitHub stars | ★ 8.7K | ★ 1.5K |
| License | Apache-2.0 | Apache-2.0 |
| Written in | Rust | TypeScript |
| Last push | 2026-11-04 | 2026-06-18 |
| Forks | ⑂ 1.2K | ⑂ 116 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick utopia if
- You weight community size — 8.7K stars and counting
- You want the Apache-2.0 license terms
- Your stack matches Rust
- You value the larger contributor base for long-term maintenance
pick simba if
- You want the simba feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches TypeScript
- You evaluated both and simba fits your workflow better
About utopia
Utopia Philosophy · Quick start · Features · Roadmap The enterprise world model built by DeepLethe. It is the first open substrate for knowledge engineering that learns passively and governs itself. Where a knowledge graph or a vector store works to hold present knowledge, Utopia puts time awareness and ontology in the base layer: the knowledge system evolves as material arrives, and conflict detection, reasoning and decision making all run against that ontology. It deploys offline, so a company can stand up a knowledge foundation, a decision core its agents can trust, and a compliance audit trail on hardware it…
read the full utopia overview →
About simba
High Efficiency Customer Service Assistant See how easy it is to integrate Simba into your website What is Simba? Simba is an open source customer service assistant built for teams who need full control over their AI. Unlike black box solutions, Simba is designed from the ground up around evaluation and customization , so you can measure performance, iterate fast, and tailor the assistant to your exact needs. Why Simba? Key Features Evaluation First Design Track retrieval accuracy, generation quality, and latency out of the box. Know exactly how your assistant performs. Fully Customizable Swap embedding models…
read the full simba overview →
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Frequently asked questions
Is utopia or simba more popular?
utopia has 8,667 GitHub stars and simba has 1,547. utopia has the larger community by that measure.
Are utopia and simba free?
Both are open source. utopia is licensed under Apache-2.0 and simba under Apache-2.0. Neither carries a licence fee.
What is the difference between utopia and simba?
utopia is written in Rust and simba in TypeScript. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, utopia or simba?
Choose utopia if you want the larger community (8,667 stars) or its Apache-2.0 licence terms. Choose simba if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.