Building SaaS in 2026: Are you vibecoding your own product or engineering it the "old way"?

I vibecoded the initial prototype and then went back and re-engineered the parts that actually matter. That's the middle ground nobody talks about and I think it's the right answer for most technical founders.

The thing is, agentic coding is inevitable. The product scales, the economics usually don't. So the question isn't vibecode vs engineer, it's which parts need to survive contact with production and which parts just need to exist. I vibecoded everything that isn't core infrastructure and I don't regret a single line of it. Speed to feedback is everything when you have zero users.

The one thing I refuse to cut corners on: anything that touches reliability in production. Bad architecture you can refactor. Bad reliability habits you carry into your production system will kill you.

You can still vibe code, but in a more disciplined engineering way: step by step, with a plan, architecture first, and create MD files with the whole plan when needed.
Start with the architecture, ask for tests first, think through the test cases, and verify the results. Use AI like a junior or mid-level engineer, and also as a brainstorming partner when you’re the only one in the room. That approach works well for me.
The key is not to ask it to build the whole thing at once, but to move step by step - just like you would when delegating to your team.

I have started vibecoding MVPs but keep one rule: the problem must be validated before the architecture is — refactoring later is cheaper than building the wrong thing slowly.