I've watched developers who clearly know their stuff completely fall apart in interviews (me being one of them). Not because they didn't know the answer they did. They just couldn't get it out of their head and into words under pressure.
It's more common than people admit.
The problem is how most of us prepare. We read docs, do LeetCode, maybe write answers in a notes app. All of that builds knowledge. None of it builds the ability to speak confidently when someone is staring at you waiting for an answer.
It's a different skill
Typing an answer and speaking one are not the same thing. When you type you can pause, delete, restructure. You have time. When you're in an interview you have to think and talk at the same time, stay on track when you lose your thread, and sound like you know what you're talking about even when you're figuring it out as you go.
The only way to get better at that is to actually do it. Out loud. Repeatedly.
What I did about it
I built DevPrep.app because I kept finding myself in interviews where I knew the answer but couldn't say it clearly. The AI asks you a question out loud, listens to your spoken answer, gives feedback and asks follow-ups. It feels closer to a real interview than anything else I tried.
It covers Azure, C#, React, TypeScript, Docker, Kubernetes, Python, SQL, Terraform and more. Free tier, works in your browser.
A few things that actually help
Record yourself. It's uncomfortable. Do it anyway. You'll hear filler words and unclear explanations you'd never notice otherwise.
Practice your worst topics most. Everyone has a weak area they avoid. Interviewers always seem to find it.
Explain it simply. If you can explain a concept to someone non-technical, you can explain it to anyone. Clarity beats jargon.
Time your answers. Aim for 90 seconds to 2 minutes. Too short seems unprepared, too long loses people.
Don't script it. Learn the 3-4 key points per topic and practice hitting them naturally, not word for word.
The honest truth
The developers who interview well aren't always the most technically skilled. They're the ones who've practiced saying their answers out loud enough times that it stops feeling weird.
That's really all it is.
devprep.app
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