Transforms
Transforms patch the body of a live response — upstream or mocked — with ordered rules. Real data, one thing different.
"I need this exact account, but with the subscription expired."
"And tomorrow I'll need it expired last week."
"And Ana needs the same thing, with the same fake email, or the screenshots won't match."
Two-pane diff with changed lines highlighted — same as the in-app editor.
status walks the whole tree. meta.version follows a dotted path and fans into arrays. tasks.*.priority hits every item. tasks[-1].id takes the last one. tasks[?status=='open'].priority filters first, then sets. Click a field path in the preview to fill the rule for you.
In-product visual
now, now+3d, now-1h, formatted as ISO or epoch. Set a scenario's clock to frozen and every now in it stops moving, so the state you share today is the state your teammate sees tomorrow.
In-product visual
Seeded generators for uuid, name, email, address, phone, company. Same scenario, same field, same value — for every teammate, every run. Your screenshots match. Your snapshot tests stop flapping.
In-product visual
Clear an array for the empty state. Truncate to the first N. Repeat to length 500 and find out what your list virtualisation really does. Remove items matching a condition.
In-product visual
Unlike mocks, every matching transform runs: global first, then the active scenario's, then your session's. Later writes to the same field win, and the Traffic log detail shows exactly which transform ids ran and which rule indexes fired — including expression errors.
In-product visual
Define a transform({ body, req, ctx }) function and return the new body. You get the parsed body, the inbound request (method, path, query, body, path params), ctx.now from the frozen clock, and ctx.seed from the scenario. Scripts run isolated on a sandbox worker; if one throws, the body passes through unchanged and the error lands in the log trace instead of on your tester's screen.
In-product visual
| The job | Reach for |
|---|---|
| Replace the whole response (empty cart JSON, a 500 body) | Mock |
| Change one nested field on live upstream data | Transform |
| Empty or pad a list | Transform (clearArray, truncateArray, repeatToLength) |
| Force a 429 with a Retry-After header | Mock (status + headers) |
| Same fake email for every teammate in a scenario | Transform + scenario seed |
They compose: mock the status, transform the body.
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