All packsPlay Billing MachinerySolve
google play rtdn purchasetoken no purchase state included
RTDN tells you something changed. It never tells you what.
A Real-time Developer Notification carries a purchaseToken and a type, never a state -- Google says explicitly you must call the Developer API afterward (decision 2).
This is one of the things Play Billing Machinery already handles. Sell subscriptions in your Android app on the Billing Library version Google requires from 31 August 2026.
Is this you?
A handler that switches on notificationType and writes entitlement directly from the notification body is wrong even when it looks right, because the notification never carries the purchase's actual state -- only a purchaseToken and a type. Google's own docs state plainly that RTDN notifications "tell you only that the purchase state changed," not what it changed to.
Why this one is easy to get wrong
The notificationType enum reads like it should be enough -- SUBSCRIPTION_CANCELED sounds like a complete instruction. Nothing about the payload shape signals that a second, mandatory network call to the Play Developer API is what actually tells you whether the subscription is entitled, on hold, or already expired again since the notification fired.
What you get instead
Every notification triggers a fresh purchases.subscriptionsv2.get (or .products.get) read before any entitlement decision is made -- the notification is purely a doorbell that says "go check." This is also why the pipeline's enrich step runs in the worker rather than inline in the push handler, since that Play API round trip can't happen inside a 10-second ack window.
Source: ARCHITECTURE.md decision 2 — checkable in the pack you receive
How you actually use this
You don’t install a library or wire up an SDK. Your own coding agent builds the code in your project, and you keep it — no runtime dependency on us.
Step 1
Download and unzip
You get a folder: the docs that tell an agent what to build, a starting skeleton, and the test suite that decides when it's done.
Step 2
Open it in Claude Code or Cursor
Point your coding agent at the folder. Nothing to install, no account with us, no API key.
Step 3
Paste one prompt
The pack contains the exact prompt. Paste it as your first message and leave it alone — it works through the build itself, choosing a cheaper or stronger model per task.
Step 4
Run ./verify.sh
One command. It prints a pass or fail for every check. Green means the build is done — the same script we ran to produce the receipt on this page.
Typical build: about 33 minutes of your agent working, mostly unattended. Then you integrate the working module into your app the way you would any code you’d written yourself.
Why you can believe this
3 of 3 runs passedWe ran this pack from an empty folder 3 times and published exactly what happened — every check, the model, the token cost, the wall time. Not a testimonial, and not our opinion: the same verify.sh you run yourself. Read the full receipt →