> For the complete documentation index, see [llms.txt](https://docs.unbrowse.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.unbrowse.ai/architecture/architecture.md).

# Architecture — Start Here

These documents describe Unbrowse 11.1.1.

* [Overview](/architecture/overview.md) — system boundaries and the request lifecycle
* [CLI and local engine](/architecture/cli.md) — commands, capture, and replay
* [Backend](/architecture/backend.md) — route graph, accounts, credits, and API contracts
* [Frontend](/architecture/frontend.md) — public site and account UI
* [Identity and auth](/architecture/auth.md) — API keys and site credentials
* [Privacy](/architecture/privacy.md) — what stays local and what may be published
* [Performance](/architecture/performance.md) — cache, fallback, and measurement
* [Security](/architecture/security.md) — trust boundaries and operational controls
* [Acceptance criteria](https://github.com/unbrowse-ai/unbrowse/tree/main/docs/architecture/ACCEPTANCE-CRITERIA.md) — release behavior
* [Test specifications](https://github.com/unbrowse-ai/unbrowse/tree/main/docs/architecture/TEST-SPECS.md) — required witnesses

The governing principle is simple: resolve a known route first, use a browser when the route is missing, and report the real outcome of both paths.