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Reliability engineering · 2026
Exact / Bouw7 Booking Integration
A crash-safe 'Confirm and send to Exact' flow that books issued material lines from a client's stock and project tool into the Exact / Bouw7 ERP. Idempotent and resumable, so a retry after a partial failure never double-books a line.
snapshot
- type
- Reliability engineering
- period
- 2026
- source
- Private client project · NDA
- build
- Solo · in production at a client, verified against the Exact sandbox first
problem
Booking material lines into an external ERP is a money path: the network write can fail after some lines are already booked, and a naive retry would book them again. The flow has to stay correct under partial failure and safe to roll out without ever touching real bookings by accident.
outcomes
Live in production at a client, after being verified end to end against the Exact sandbox first
A retry after a partial failure never double-books a material line
Replaced an error-prone manual ERP entry step with a one-click, auditable booking
what i built
Idempotent booking via a per-line marker, so a retry skips lines already sent
Resumable after a partial failure: on error it stops, holds the project in 'Ready for Exact', and reports 'X of Y lines booked'
The external ERP call is kept outside the database transaction, so a failed send never leaves a half-committed local state
A confirm-lock that blocks a double confirm, so the same project cannot be booked twice at once
A runtime three-state switch (off / dry-run / live): dry-run logs the exact payload without booking, and the flag defaults to off
Push, idempotency, partial-failure, and dry-run paths covered test-first
tech stack
Django REST FrameworkCeleryPostgreSQLReact 19TypeScriptViteMantineExact / Bouw7 API
Case study
This project is documented here as a case study; the source is not published as a public repository.