Designing before building

The decisions to take FIRST: pattern, idempotency key, failure handling and tracking. Written down BEFORE the first connection is created. All four are cheap now and expensive later, which is the only reason to insist on the order. Each one, retrofitted, means rebuilding a flow that already works. THE PATTERN. Scheduled, given a file arriving nightly — Module 7. Batch rather than per-record, given the volume constraint — Module 14 Lesson 2. Write down the record count you are designing for and the window you must fit in, because those two numbers are what make the choice defensible to somebody reviewing it. THE IDEMPOTENCY KEY, AND THIS IS THE HARDEST OF THE FOUR. The partner resends, so what makes a row unique? A reference in the file, if there is one. A composite of fields if there is not — and Module 9 is explicit that choosing the key is…

In this module: Module 18 · Capstone: one integration, delivered

1. 1The brief
2. 2Designing before building
3. 3Building it
4. 4Proving it
5. 5Promoting and handing over
6. 6Where to go next