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Day 29 - Mock InterviewOverview

Day 29 — Mock Interview

Twenty-eight days of patterns, structures, and trade-offs. Today is game day. Knowing the algorithms is necessary but not sufficient — the interview is a performance, and the performance has a script, a clock, and a rubric. This chapter is your dress rehearsal: the exact loop you’ll walk, the minute-by-minute flow of each round, live narrated mock problems, and — crucially — what the interviewer is silently scoring while you talk.

It’s built to feel like the real thing. There’s a phase stepper that paces you through a 45-minute coding round, a live practice timer, a STAR-answer builder that grades your behavioral stories, and a breakdown of what Google, Meta, Amazon, Apple, Netflix, and Microsoft each weight most.

The hiring loop — tap a stage
Technical Phone Screen · 45–60 min
1–2 coding problems in a shared editor (no autocomplete, no run button on some). Usually one medium. Pass bar: working code + clear communication. This is where most candidates are cut.

What you’ll learn today

  • The full hiring loop — recruiter screen → phone screen → onsite → debrief → offer, and what each gate filters for
  • The coding round, minute by minute — the CLARIFY → EXAMPLES → APPROACH → CODE → TEST → COMPLEXITY framework, with a time budget and the trap that loses each phase
  • Three live mock problems — narrated end-to-end exactly as you’d speak them aloud, including the clarifying questions and the bug you’d catch in testing
  • The behavioral round — the STAR method, an interactive answer-builder, and Amazon’s Leadership Principles
  • The system design round — how it plugs into Day 28, at interview pace
  • The rubric — the four signals every interviewer scores (and the red flags that sink a loop), plus day-of logistics
  • Company-by-company emphasis — Google vs Meta vs Amazon vs Apple vs Netflix vs Microsoft

The single most important reframe of this entire chapter: the interview is not “did you get the answer?” — it’s “would I want to work with this person on a hard problem?” Interviewers score problem-solving, coding, communication, and verification. A candidate who thinks out loud, scopes the problem, and finds their own bug on a sub-optimal solution often beats a silent candidate who types the optimal answer with no explanation. Communication is not a soft skill here — it’s half the grade.

Roadmap

  1. The Interview Loop — every stage of the process, what it filters for, and how Google / Meta / Amazon / Apple / Netflix / Microsoft differ.
  2. The Coding Round — the 6-phase framework with an interactive phase stepper and a real countdown timer for self-practice.
  3. Live Mock Problems — three problems walked through out loud, the way a strong candidate actually sounds.
  4. The Behavioral Round — STAR, the interactive story builder, and Leadership-Principle mapping.
  5. The System Design Round — the design interview at speed, linking to the Day 28 toolkit.
  6. Rubric & Red Flags — how you’re scored, what tanks a loop, and the logistics of the day itself.
⚠️

You cannot cram this the night before. Communication under pressure is a trained skill — it has to be rehearsed out loud, on a whiteboard or plain editor, on a clock, ideally with another human. Reading this chapter is step one; doing three timed mock problems talking the whole time is step two, and it’s the one that actually moves your performance.

This is Day 29. Tomorrow, Day 30 — Victory Lap zooms back out and ties the entire 30-day arc into one map you can carry into the room.

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