imnot

YAML in. Mock server out. Define external APIs in a single file, run imnot start, and get a fully functional local mock server — stateful flows, session isolation, and an Admin UI included. No code required.

Why imnot?

• Zero code. One YAML file per external API. No JVM, no framework, no boilerplate.
• Stateful, not just stubbed. OAuth, polling, callbacks, paginated lists, and per-test session isolation — all modeled in YAML.
• Validation-aware. Declare field rules in YAML — imnot rejects malformed requests with realistic 422 errors before returning a mock response.
• Rate-limit aware. Declare a requests_per_minute ceiling on fetch endpoints — imnot enforces it with a token bucket and returns realistic 429 responses with a Retry-After header.
• Ships with your tests. Partner definitions are version-controlled alongside the integration they test and run anywhere Docker runs.

Quick start

Requires Python 3.11+.

pipx install imnot
imnot init
imnot start

pipx installs CLI tools into isolated environments. Alternatively: pip install imnot inside an existing virtual environment.

imnot init creates a partners/ directory with two working example partners (staylink and bookingco) that cover all six patterns. Edit or replace them whenever you're ready.

Patterns

All fetch, polling, and paginated endpoints support X-Imnot-Session for per-test isolation — parallel test runs stay independent.

→ Full pattern reference with YAML examples

Admin UI

imnot ships an embedded Admin UI at GET /imnot/admin/ui. No setup required — it's enabled by default and auth-gated by the same Bearer token as the rest of the admin API.

From the browser you can:

• Browse loaded partners and their datapoints
• Upload and inspect payloads (global or session-scoped)
• Run end-to-end endpoint tests — including full polling flows
• Manage active sessions
• Hot-reload YAML without restarting the server
• Run load tests against any HTTP endpoint (standalone or partner-bound)

→ Load Test reference

AI-ready

Don't want to write the YAML yourself? Paste one of these into Claude, ChatGPT, or your AI assistant:

From a description:

I use imnot to mock external APIs for integration testing.
Generate a partner.yaml file in imnot format for [service name].
Schema reference: https://github.com/edu2105/imnot/blob/main/partners/README.md
Endpoints to mock: [describe them]
Output only the YAML — no code, no explanation.

From an OpenAPI spec:

I use imnot to mock external APIs for integration testing.
Convert this OpenAPI spec into a partner.yaml file in imnot format.
Schema: https://github.com/edu2105/imnot/blob/main/partners/README.md
Output only the YAML — no code, no explanation.
[paste your spec here]

Learn more

Limitations

• Callback retries — no built-in retry logic; use the retrigger endpoint to re-fire.
• JSON only — response bodies are always JSON, no XML support.
• Single-node — SQLite session store is not shared across instances.
• Admin UI — desktop layout only; no mobile breakpoints.
• No native TLS — use a reverse proxy (Nginx, Caddy) to terminate HTTPS.