API & requirements cleanup
If your rounds land on "we never got to the interesting parts", the fix is here. Faster requirements, tighter APIs, idempotent writes.
For: Engineers who run out of time before reaching the architecture
After this path
Frame a prompt, bound its scope, and draft a defensible API contract in under 10 minutes.
- 1Skill
Requirements & scope framing
Separating functional from non-functional, surfacing assumptions, bounding scope.
Why this, here: Turn vague prompts into a designable problem in 5 minutes.
- 2Skill
Capacity estimation (back-of-envelope)
Deriving QPS, storage, bandwidth, memory from user-facing numbers.
Why this, here: Defensible numbers unlock every later decision.
Checkpoint
Time-box drill: set a 5-minute timer and scope + estimate a new prompt (“design a coupon service”). Writing ends at the beep. If you didn’t reach numbers, the front-half is still too slow.
- 3Skill
API contract design
Resource modelling, idempotency, pagination, error semantics.
Why this, here: Resource modelling, pagination, error shapes.
- 4Deep dive
Idempotency
Retry-safe writes with idempotency keys, dedupe windows, and response replay.
Why this, here: Non-negotiable for payments, order creation, anything retry-safe.
- 5Skill
Data model design
Entities, relationships, keys, normalization vs denormalization.
Why this, here: Entity model before storage. Seniors don't skip this.