Planning a web app before development starts

Start with roles: who uses the system, what they must accomplish, and what they must never be able to do. Security and clarity improve when roles are explicit.

Define workflows as steps with inputs and outputs—not as screens. Screens come later; the workflow is the truth.

Agree on acceptance criteria in business language: what does ‘done’ mean for the first release? What is explicitly out of scope?

Finally, map integrations early. The hardest surprises usually live at system boundaries—auth, data formats, webhooks, and legacy constraints.