No account, no schema, no configuration. Every array in what you paste becomes an endpoint — and the chaos controls work on it, so you can force a 503 against your own shapes rather than someone else's sample data.
No data yet, but your API has an OpenAPI spec? Generate from OpenAPI writes believable records from it for you.
Expires . This page keeps it until then — refresh, or come back later, and it will still be here. Export it below if you want it for longer; that file runs on your machine and never expires.
| Resource | Records | URL |
|---|
This is the part no other mock service does — your data, failing how you ask.
A hosted mock is useful until it expires, nine days at most. These files run offline, in CI, and long after this service is gone.
# one file, no install, no network — and the chaos controls still work node mock-server.mjs python3 mock_server.py java MockServer.java dotnet run MockServer.cs # then, on your own machine: curl 'http://localhost:4000/todos?_status=503' curl 'http://localhost:4000/todos?_fail_rate=0.3'
All four servers are self-contained: your data is embedded in the file and
parsed at startup, so there is nothing to install and nothing to fetch — no
npm, no pip, no Maven, no NuGet. They answer identically, byte for byte, so
the language is a preference and not a compromise.
They carry the same controls as the hosted API, which is the
part json-server cannot do — it will serve db.json
happily, but it cannot fail on demand.