Describe the Sequence
Where you'll practice this
5 Promptles scenarios teach this principle directly. Each one drops you into a real engineering ticket and asks you to write the prompt you'd send to Claude Code.
The Race Condition
Your inventory system in `services/inventory.ts` has a critical bug. Two async functions, `reserveStock` and `processOrder`, both read the current stock count, then update it. When two orders come in at the same time for the same product, both read the same stock value (e.g.,…
The OAuth Flow
You need to build a simple Express web app in a file called `calendar-app.js` that authenticates users via Google OAuth 2.0 and displays their upcoming calendar events. The flow is: (1) user visits `/auth` and gets redirected to Google's consent screen, (2) Google redirects back…
The Chained Login
Your QA team has a Postman collection that hits authenticated endpoints on your internal app. Every request needs an `Authorization: Bearer <jwt>` header, but the JWT expires after 15 minutes, so manually pasting it gets old fast. The login endpoint is `POST /auth/login` with…
Run TDD End-to-End
You're adding a `formatRelativeTime(date)` helper to your project's date-utils library. It returns 'just now' for less than a minute, 'N minutes ago' for under an hour, 'N hours ago' for under a day, 'N days ago' for under 7 days, and a formatted absolute date for anything…
Checkpoint the Migration
Your team needs to rename a critical column — `users.display_name` becomes `users.full_name` — across a 50-million-row Postgres table that backs every login. The textbook approach is six steps: (1) add the new `full_name` column nullable, (2) backfill from `display_name`, (3)…