Design Gurus Mock Interviews

What it offers

• System design mock interview: open-ended architecture questions such as scaling a distributed system or building a fault-tolerant service, with feedback on design decisions, trade-offs, data modelling and API choices. Aimed at mid-level, senior, staff, backend, infrastructure and ML systems candidates.
• Coding mock interview: live data structures and algorithms problems, with feedback on problem solving, edge cases, complexity and communication. Python, Java, JavaScript, C++, Go and other mainstream languages are supported depending on the interviewer.
• Target-company mock: practice calibrated to a specific company and level (for example Google, Meta, Amazon or Microsoft), with an interviewer from that company where available.
• Behavioural mock: practice with STAR-style answers for leadership and situational questions.
• One-to-one coaching for anything else, such as strategy, job search and negotiation.

When booking you choose the interview type, your level (junior, mid, senior, staff and above, or manager) and the interviewer background.

Price and what is included

As of September 2026 the page lists:

• System design mock: $159 with an interviewer from a large tech company, or $215 with one from your target company (shown as discounts from $199 and $269)
• One-to-one coaching: $149, or $215 for a target-company interviewer

Each session is about 60 minutes including the debrief. You receive a verbal debrief and a prioritised list of fixes, topics and drills, plus post-session resources and templates. The page offers a satisfaction money-back guarantee and states a 95% success rate, more than 1,000 engineers helped and a 40% average salary lift (the provider's own figures).

Why a live mock is worth it

Solving problems alone and solving them while someone watches are different activities, and the second is the one you are assessed on. Under observation, candidates discover that they narrate poorly, freeze on the first follow-up, or spend twelve minutes on requirements that should take four. None of that shows up in solo practice, and all of it is fixable once you see it.

Timing it well

Book after you have covered the material and before the real loop, with enough time to act on the feedback. Around two weeks before the interview works well. For a full onsite, many candidates book one coding and one system design mock to simulate the loop, then a second round to check the fixes.

How to get the most from it

• Choose the round you are least confident in for the first mock.
• Use your real interview language and the level you are targeting.
• Treat it as the real thing: quiet room, camera on, no notes.
• Write down the fixes from the debrief immediately and turn them into drills for the following days.
• Prepare with the matching course first, such as Grokking the Coding Interview or Grokking the System Design Interview, so the mock tests your readiness rather than teaching the basics.

Best for: candidates with real interviews scheduled who have never rehearsed under observation.