A few months ago, in the same week, I read two headlines that had no business existing at the same time. One was about a company bragging that its engineers had basically stopped writing code — AI was doing it for them. The other was about a different company quietly rehiring the senior engineers it had laid off a year earlier, because the AI-built version of their product kept shipping bugs a human would have caught in code review. I run mock interviews for engineers trying to land their next role, and I teach backend development on this channel, so I hear both sides of this panic constantly — from people worried AI is about to make their job irrelevant, and from hiring managers quietly telling me the opposite. I wanted to stop going off vibes and actually dig into what was happening with real numbers. What I found didn't fit neatly into either the "AI is taking our jobs" camp or the "AI is overhyped nonsense" camp. It's stranger than both, and honestly...
Part 8 of Building Instagram's Authentication Backend . If you're just joining, the repo is here and you can catch the earlier parts on the YouTube playlist . We built an engine with no ignition Here's where we actually stood after seven parts of this series. We had a fully working AuthService — register, login, refresh, the works. We had a security layer sitting on top of it, filtering every request, deciding who's allowed where. We had entities, repositories, DTOs, a whole exception-handling backbone. And none of it had a URL. Not one line of that code could be reached from outside the JVM. No curl command, no Postman request, nothing. It's a strange feeling to have written that much working logic and still not be able to actually call any of it. So that's what this part is about — wiring up the front door. The controller, and why it's boring on purpose Here's the register endpoint, in full: @PostMapping ( "/registe...
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