The question I ask at every interview

Once, at one of my first interviews for a mobile dev position, I was asked: what does "good code" mean to you? Since then, I often ask candidates the same question at the end of interviews. Not to evaluate — more out of curiosity.

The answer is almost always the same: readable, extensible, testable. SOLID, DRY, clean architecture. Juniors, mids, seniors — almost everyone says the same thing.

I used to think the same way. I'd agonize over layer structure, debate patterns, refactor before the feature even worked. It felt like the "right" way to code.
Now, with more experience, architecture just happens. You set up a foundation, work within it, adjust as you go. You don't overthink — you just know what fits. And once that's no longer something you struggle with, the real question surfaces: how fast can I deliver this feature? Not "is this abstraction elegant enough" but "is this in prod and solving the user's problem."

AI is reinforcing this mindset. An LLM can understand your codebase and write new code within its patterns. The architecture doesn't suffer — but the delivery speed multiplies.

That said — in real production work, AI doesn't magically make everything 10x faster. The bottleneck was never really the code itself. It's communication: unclear requirements, waiting for designs, going back and forth with the client. AI eliminates the slowest part of coding, but it exposes what was always the real problem — everything around the code. Which only reinforces my point: obsessing over code perfection was always misplaced energy. But that's a topic for another post.

So if someone asked me that same interview question today, I'd answer: good code is code that solved the problem, reached the user, and did it on time. Cleanliness is a means, not an end.

A while back I started diving into system design.

I got curious about how large-scale modern systems work, how and why their architecture is shaped the way it is. Decided to step outside the mobile dev bubble (wrote about that in my previous post).

I love learning and consume a ton of educational content now: books, conference talks, articles, all mixed together. But what really clicks for me is smart people who explain complex things simply.

So here are 3 lectures I want to recommend: Oleg Bunin's talks from HighLoad++ 2017 (1, 2, 3) as a solid foundation for system design. He walks through different approaches to scaling high-load systems one by one, then gradually moves into practice. Sure, some things are dated by now, but the fundamentals hold up.

I know that at least some of my friends who are really cool engineers are reading this. If you know similar resources that explain system design in a clear way, please share, I'd really appreciate it 🙏

Fun fact: back then (in 2017) VK had only about 20 developers 🫡