Why Chub
Context Hub by Andrew Ng solves a real problem: coding agents hallucinate APIs and forget what they learn between sessions. Its solution — curated, versioned markdown docs served via CLI and MCP — works.
Chub is built on that foundation and adds three things:
1. Performance
A native Rust binary replaces the Node.js runtime:
| Metric | Context Hub (JS) | Chub (Rust) | Improvement |
|---|---|---|---|
| Search | 1,060 ms | 56 ms | 19x faster |
| Validate only | 1,920 ms | 380 ms | 5x faster |
| Build (1,560 entries) | 3,460 ms | 1,770 ms | 2x faster |
| Get (cached doc) | 148 ms | 63 ms | 2.3x faster |
Cold start (--help) | 131 ms | 44 ms | 3x faster |
| Package size | ~22 MB | 10 MB | 2.2x smaller |
| Peak memory (build) | ~122 MB | ~23 MB | 5.3x less |
| Runtime dependency | Node.js 20+ | None | Single binary |
Measured on Windows 11 with the production corpus (1,553 docs, 7 skills). Median of 5 runs. Reproduce with ./scripts/benchmark.sh.
2. Team Features
Things an individual tool doesn't need but a team does:
- Doc pinning — lock versions so agents can't use outdated APIs
- Shared annotations — "don't use the v3 pattern" committed to git, surfaced automatically
- Context profiles — backend devs get API docs, frontend gets UI docs, inherited from a shared base
- Agent config sync — one source of truth for CLAUDE.md, .cursorrules, AGENTS.md, and more
- Project context — architecture docs, conventions, runbooks served alongside public docs
- Dep auto-detection — scan 9 file types and auto-pin matching docs
- Doc snapshots — point-in-time pin captures for reproducible builds
- Freshness checks — detect when pinned doc versions lag behind installed packages
3. Full Compatibility
Identical registry format, search index, and config schema. Content authored for Context Hub works in Chub without changes. The switch is a drop-in replacement.
Who is it for
- Teams where multiple developers and AI agents need consistent context
- Projects that want git-tracked, reviewable doc configuration
- Monorepos that need path-scoped context profiles
- Anyone who wants a faster alternative to Context Hub
Design Principles
- Git-first — team config lives in the repo. If it's not in git, it doesn't exist for the team.
- Gradual adoption — works for a solo developer today; adds team value when
.chub/is committed. - Three-tier inheritance — personal -> project -> profile. No tier is required.
- Agent-native — every feature is accessible via MCP. CLI is for humans, MCP is for agents.
- Zero cloud dependency — everything works offline and locally.
- Fast — search in ~56ms, cold start in ~44ms.