Challenge
Build-to-order industrial machines need per-unit BOMs. After 20 years on FileMaker, the system became a business risk: Mac-only, 5-user concurrency cap, and only one engineer in the company who could maintain it.
Approach
Reverse-engineered every FileMaker script and layout, documented the business logic, then migrated to a web app. Data migration was lossless, and screen flow stayed familiar to FileMaker users.
Implementation
Parent-child BOM expansion runs as recursive CTEs; part master search uses Algolia for instant lookup. FileMaker calculation fields were re-implemented as TypeScript logic with full change history. CSV integration with production, purchasing, and costing is standard.
Results
Concurrent users became unlimited, with same-day access from any location. BOM edits doubled in speed, and ¥180k/month maintenance disappeared. Business continuity risk dropped sharply.