The seed-script tax: how I generate realistic test data for Postgres, Playwright and mock APIs

Two years ago I gave a demo to a prospective client. The dashboard looked great until I scrolled the customer table and the room got to enjoy asdf asdf, Test User 1, Test User 2 and a support ticket from aaa@aaa.com. Nobody said anything. They didn't have to.

That's the moment I started taking test data seriously, and it turned into a small tool I now use on every project. I'll explain the workflow first, and I'll be upfront that the tool is mine (fundata.dev) so you can discount the enthusiasm accordingly.

The problem isn't fake data. It's the seed script.

Every codebase I've worked on has some version of this file:

// scripts/seed.js — last touched 8 months ago

The seed-script tax: how I generate realistic test data for Postgres, Playwright and mock APIs

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