How do I mock the App Store Connect API locally?

Install stunt, add a one-service block to stunt.yaml (adapter: embedded:apple-appstoreconnect-style), and run stunt up. You get a local, stateful stand-in for App Store Connect API v3 — 15 routes over rest — with no remote account, no network, and no bills.

Is the App Store Connect API mock data synthetic?

Yes — entirely. The adapter returns generated data only; stunt's adapter lint rejects real-looking secrets and PII at build time. It simulates the shape and behavior of App Store Connect API (routes, status codes, pagination, webhooks), never real records.

← all adapters

apple-appstoreconnect-style

simulates App Store Connect API v3

restadapter v0.1.015 routes

verification

VMVM tier — no SDK suite yet· surface 15 · not implemented 7 · differs 7

use it

# add to stunt.yaml
services:
  apple-appstoreconnect:
    adapter: embedded:apple-appstoreconnect-style

# then
$ stunt up

The embedded: source extracts this adapter from the binary — no git clone, fully offline.

how to mock the App Store Connect API locally

Install stunt, paste the service block above into stunt.yaml, run stunt up — then point your client at localhost instead of App Store Connect API. It works offline, keeps state across requests and restarts, and every response is synthetic: the route shapes, status codes, pagination, and webhook delivery follow the real App Store Connect API v3 surface — the data is fake, the behavior is real.

backing stores

apps

api surface (15)

generated from the adapter manifest — exactly what boots, nothing more · covers 0% of the real API's 1263 routes (derived from spec App Store Connect OpenAPI Specification @ 4.4.1)

15 routes

GET/v1/apps

POST/v1/apps

POST/v1/appStoreVersionSubmissions

GET/v1/users

GET/v1/salesReports

GET/v1/apps/{id}

PATCH/v1/apps/{id}

GET/v1/apps/{id}/appStoreVersions

POST/v1/apps/{id}/appStoreVersions

GET/v1/apps/{id}/builds

GET/v1/apps/{id}/appPrices

GET/v1/builds/{id}

GET/v1/appStoreVersions/{id}

PATCH/v1/appStoreVersions/{id}

GET/v1/appStoreVersions/{id}/builds

VM-verified behaviors (20)

✓a rejected credential answers Apple's 401 errors array, not a bare status
✓the JOSE header must declare ES256 and carry a kid
✓structural validity is not enough: the exact JWT string must be registered
✓the seeded app reads back through list and single-get, with 404 NOT_FOUND for unknown ids
✓create assigns numeric ids, persists into the list, and dedupes bundleId
✓bracketed filter[...], leading-dash sort, and fields[apps] projections apply before paging
✓PATCH /v1/apps/{id} renames and refuses bundleId collisions
✓limit/cursor paging surfaces meta.paging and a links.next cursor
✓limit defaults to 50 and clamps at the documented maximum 200
✓a malformed cursor is total: 200 with data null (Apple answers 400 — deviation)
✓versionString is required and duplicate versionStrings collide per app
✓the app's first version adopts its unattached build
✓PATCH works only in the editable states (PREPARE_FOR_SUBMISSION, REJECTED)
✓submission drives WAITING_FOR_REVIEW → IN_REVIEW → READY_FOR_SALE on the clock
✓simulate_fail rejects, and a REJECTED version stays editable and resubmittable
✓a fresh app's build reads PROCESSING and the processingState filter agrees
✓the 3s window settles VALID and GET /v1/builds/{id} agrees
✓a simulate_fail app settles its build INVALID
✓users seed once and answer the bracketed role/username filters and sort
✓salesReports echoes the bracketed report filters with DAILY/SALES defaults

Not implemented (7)

No TestFlight beta testing (betaGroups, betaTesters, buildBetaDetails)
No IAP or subscriptions (inAppPurchasesV2, subscriptionGroups)
No provisioning surface — bundleIds, certificates, devices, profiles
No app metadata: localizations, ageRating, categories, phased release
No customer reviews endpoints (customerReviews and responses)
No user invitations or user CRUD (GET /v1/users list only)
No App Analytics (analyticsReportRequests, metrics) — salesReports only

Differs from the real API (7)

JWT signature crypto NOT verified — structural plus registry check only
Review is clock-driven: WAITING_FOR_REVIEW +1s to IN_REVIEW, +3s to READY_FOR_SALE
Builds settle PROCESSING to VALID at +3s — no separate in-flight state
simulate_fail extension: app create forces build INVALID, version create REJECTED
A first build is minted at app create — no build upload path
A malformed cursor answers 200 with data null; real ASC answers 400
salesReports returns a JSON:API object; real ASC streams a gzip TSV and 400s on missing filters

full scorecard →

want more of the App Store Connect API surface? adapters are YAML + Starlark — the authoring guide covers adding routes, fixtures, and state machines. Open an issue for anything big first, or just file a PR — merged routes ship in the next release.