Series
Applied Patterns
Ten real problems, each needing several patterns at once. The context before, the shape of the failure, the properties the answer has to have, the candidates from both catalogues weighed against those properties, the assembly, the implementation, and what the system looks like afterwards. Draws on Patterns, Integration and Data Structures. Part of Under the Hood.
The Same File Twice
A supplier's scheduler fired twice on the night the clocks went back, the same stock file landed twice, and 340 lines were credited with 9,840 kg that arrived once. Nobody found it for twenty-three days, by which time the automatic reorder had gone out short three Mondays running and a caterer and a restaurant had been let down. The hard half of the fix is not spotting the repeat; it is telling a repeat from a correction.
Coming soon