AI tool comparison
Onyx vs Terrarium
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Developer Tools
Onyx
Self-hosted AI platform with RAG, agents, and 50+ connectors — MIT licensed
75%
Panel ship
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Community
Paid
Entry
Onyx is a fully open-source, self-hostable AI platform that wraps any LLM with enterprise-grade features: retrieval-augmented generation (RAG), deep research flows, custom agents, code execution, image generation, and voice mode. It connects to 50+ data sources via indexing connectors or MCP, making it a full internal AI stack rather than a chat wrapper. The platform recently shipped version 3.1.1 and has accumulated 24.8k GitHub stars. Unlike managed AI platforms, Onyx is self-deployed — teams can run it on Docker, Kubernetes, or Helm, and the Community Edition is entirely MIT licensed with no feature gating. Enterprise features like SSO, RBAC, and audit logging are available for teams that need them. What sets Onyx apart is the combination of depth and openness. Most open-source chat UIs are thin wrappers. Onyx ships agentic RAG that ranked on deep research leaderboards, plus an admin layer for managing connectors, access control, and usage analytics — all without sending data to a third-party cloud.
Developer Tools
Terrarium
Evals that actually simulate real deployment — stateful, multi-turn, alive
50%
Panel ship
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Community
Paid
Entry
Terrarium is a multi-turn evaluation and optimization engine for LLM agents built by evolvent-ai. Unlike static benchmark suites that measure agents against fixed input-output pairs, Terrarium creates persistent, stateful "living environments" — simulated deployment contexts where agents operate over extended sessions, accumulate state, use tools, and interact with simulated external systems. You evaluate agents the way you'd test a car: by driving it, not by measuring its doors. The system supports configurable environment complexity, including simulated databases, APIs, file systems, and user personas. Agents are scored not just on final outputs but on trajectory quality — how efficiently they reached the answer, how often they hallucinated intermediate steps, and how well they recovered from dead ends. The engine also supports continuous optimization loops where poor-performing trajectories trigger automatic prompt refinement. With 17 stars and created April 14, Terrarium is extremely new. But it's addressing a genuine gap: the disconnect between how agents perform on static benchmarks versus how they behave in production. As enterprise AI deployments scale, the need for realistic pre-production evaluation is becoming critical.
Reviewer scorecard
“50+ connectors out of the box plus MCP support means you can actually index your entire company knowledge base without writing glue code. Self-hosting on Docker took about an hour to get running. This is what I wanted Danswer to become — and it did.”
“Static evals are lying to us constantly — agents that ace benchmarks fall apart in production because benchmarks don't have state, side effects, or accumulated context. Terrarium's living environments model is the right approach to catching real failure modes before deployment.”
“Self-hosting an enterprise AI platform is not trivial — you own the infra, the updates, the security patches, and the connector maintenance. For small teams without a dedicated DevOps person, the operational overhead will eat the productivity gains. The MIT license is genuinely free until you need the enterprise features, at which point the pricing is opaque.”
“Building a realistic simulation of your production environment is often harder than just running the agent in staging. The value proposition assumes your eval environment is meaningfully closer to production than your existing test suite — which is a big assumption for complex deployments.”
“The open-source enterprise AI stack is the play for companies that can't trust their proprietary data to third-party clouds — which is most regulated industries. Onyx is building the infrastructure layer for sovereign AI deployments, and 25k stars suggests the market agrees.”
“The eval-optimize loop is the missing piece in most AI agent development workflows. Tools that can automatically identify weak trajectories and suggest improvements will become as fundamental as unit tests. Terrarium is early, but the category is inevitable.”
“Deep research that actually cites your internal docs rather than hallucinating sources is genuinely useful for content teams. The voice mode and image generation being bundled in means one deployment covers most creative workflows.”
“This is deeply technical infrastructure that won't affect my daily workflow. The people who need this know they need it — but for most creators building with AI tools, static evals are already more than they use.”
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