Systems | Development | Analytics | API | Testing

At Ably we've been able to make a transformational change in how we build SDKs as a result of what's now possible with LLMs. In this post, I explain how.

Writing test cases sounds simple until you're actually doing it. You read a requirement, try to figure out what "done" even means for it, write out steps, realize you missed three scenarios, go back, revise, and by the time you feel okay about it, the sprint has moved on without you. This happens to every team working at any real scale. It is just what manual test case creation costs you, and it is the problem autonomous test generation was supposed to solve at a category level.

A developer writes a function. That function gets wired into a module. The module joins the rest of the application. And at some point, someone outside engineering has to decide whether the whole thing is actually good enough to ship. Four different moments, four different kinds of testing, that’s the whole idea behind levels of software testing.

Your team shouldn’t have a trade-off between mobile app delivery speed and quality. Here’s how to ship with confidence.

Spring Boot version upgrades—whether moving from 2.x to 3.x, 3.x to 4.x, or even minor bumps like 3.2.5 to 3.3.1—regularly introduce subtle, breaking changes that unit and integration tests miss. JSON serialization shifts, autoconfiguration reordering, and transitive dependency conflicts can silently alter your API contract.