System Design Mock Interview + Written Feedback with Roni Das

What happens in the call

• We meet on a 60-minute video call. I play the interviewer.
• I give you a real system design question at your target level (mid, senior or staff). Tell me the company and role in the booking form and I will choose a question that fits.
• You lead the design on a shared whiteboard: requirements, rough scale numbers, high-level design, data model, deep dives and trade-offs. I push back and ask follow-ups the way a real interviewer does.
• The last 10 to 15 minutes are spoken feedback.

What you get after the call

• A written feedback report within 48 hours: what went well, where you lost points, and what a strong answer to the same question includes.
• A short list of topics to study next, in order.

Who it is for

Engineers preparing for system design rounds, from a first high-level design round to senior and staff loops.

Before the call

Use a laptop with a stable connection. Any whiteboard tool you know is fine; Excalidraw works well.