A couple of months ago I came across a product called Keploy on LinkedIn. I went to their site to read about it, and the pitch stopped me: it writes your integration tests for you by watching your app run.

I went like --

And it did that by Not generating them from your code. Watching actual traffic. You run your app, use it normally, and Keploy records what came in and what went out. Later it replays those requests against your app and checks it still responds the same way.

I wanted to see whether that held up,

so I ran one of their Go quickstarts end to end on Windows through WSL. This is what it was like.

How it works

Integration tests usually mean keeping a database alive, writing mocks by hand, and updating those mocks every time a schema changes. It's a lot of upkeep for tests that mostly verify things you already know work.

Keploy's approach is to record once and replay forever.…