Show HN: UltraContext – A simple context API for AI agents with auto-versioning
ofabioroma Wednesday, January 21, 2026Hey HN! I'm Fabio and I built UltraContext, a simple context API for AI agents with automatic versioning.
After two years building AI agents in production, I experienced firsthand how frustrating it is to manage context at scale. Storing messages, iterating system prompts, debugging behavior and multi-agent patterns—all while keeping track of everything without breaking anything. It was driving me insane.
So I built UltraContext. The mental model is git for context:
- Updates and deletes automatically create versions (history is never lost)
- Replay state at any point
The API is 5 methods:
uc.create() // new context (can fork from existing)
uc.append() // add message
uc.get() // retrieve by version, timestamp, or index
uc.update() // edit message → creates version
uc.delete() // remove message → creates version
Messages are schema-free. Store conversation history, tool calls, system prompts—whatever shape you need. Pass it straight to your LLM using any framework you'd like.What it's for:
- Persisting conversation state across sessions
- Debugging agent behavior (rewind to decision point)
- Forking contexts to test different flows
- Audit trails without building audit infrastructure
- Multi-agent and sub-agent patterns
What it's NOT:
- Not a memory/RAG system (no semantic search)
- Not a vector database
- Not an Orchestration/LLM framework
UltraContext handles versioning, branching, history. You get time-travel with one line.
Docs: https://ultracontext.ai/docs
Early access: https://ultracontext.ai
Would love feedback! Especially from anyone who's rolled their own context engineering and can tell me what I'm missing.