Start with user roles: who signs in, what they must do, and what they must never see. Capture happy paths and edge cases—voided invoices, partial refunds, HIPAA minors, etc.
Prioritize ruthlessly. Phase one should ship a usable workflow; phase two adds automation and reporting.
Written acceptance criteria (“Given/When/Then”) reduce debates at the end of sprints.
Buy when your process matches the product; build when your process is the differentiator.
Software is never “done”—platforms, browsers, and threats move constantly.
Well-designed APIs let your custom app coexist with QuickBooks, Salesforce, EMRs, or ticketing systems.
Internal apps are tempting targets because they sit behind “obscurity”—until they are not.