Android system design
and coding interview prep.
Full breakdowns, AI-guided practice on a live canvas, mock interviews, and peer practice with another engineer.
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Interview guides and curated questions for 48 companies
Pick your track.
Full system breakdowns, with interactive visuals
Android architecture walked end to end - deep dives, step-through visualizations, AI-guided practice, and mock interviews.
DSA fundamentals - visual breakdown of each algorithm
Every core pattern stepped through visually, then practiced with LeetCode-style sets, coding challenges, and code review rounds.
Watch the mechanism, not just the diagram.
Full system breakdowns ship with step-through visualizations - convergence, ordering, buffering - so you see the design move, not only read the claim.
Every algorithm, stepped through.
Each DSA concept walks the algorithm visually - queues filling, pointers moving, trees expanding - so the pattern sticks before you hit the practice set.
Read it. Practice it. Defend it.
Every system design breakdown links to a live canvas where an AI coach walks you through the design step by step. Then hand it to the AI interviewer for a mock round with a Pass/Hold verdict.
Run them in your browser.
The actual questions from real rounds, with multi-level test cases that catch what interviewers catch.
Practice with a real peer.
Live coding and system-design rooms with shared voice. Two free interviewee sessions; Premium unlocks unlimited with a give-one-take-one balance.
Backend system design, AI engineering, and infrastructure rounds are being built now.
Start free. Go deeper when you're ready.
Core concepts and sample breakdowns are free. Premium unlocks the full catalog, AI mock interviews, guided practice, and unlimited peer interviews.
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