CA
Architecture workbench
System Design Lab / Case studies soon
v2.4 live environment
02 / request path / PAY
Payment gateway
Trace one request through the system and inspect the decisions that keep it correct under pressure. Real-world payment gateway problems I have solved in production are being added next.
request lifecycle
step 01 / 04Failure drill
Duplicate requests must not create duplicate charges.
Active boundary
Request
Validate amount, currency, customer, and idempotency key.
Primary invariant
Correct once
Retries preserve the same outcome.
Review status
Inspecting
Architecture is ready for critique.