Prep Library
Browse the full catalog by domain. Open a domain to see its exhaustive list of topics, then tap any topic for a worked detail.
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Coding
Pattern-based problem solving
Topic-based, company-tagged problem patterns. Open a pattern for a worked guide, or jump straight into a tagged problem with a full solution.
Browse libraryAlgorithms & Data Structures
Foundations from first principles
The data structures and algorithm families every technical interview assumes you know cold — each with intuition, complexity, and a reference implementation.
Browse librarySystem Design
Scalable architecture walkthroughs
End-to-end scenario walkthroughs: business requirements, technical requirements, capacity estimation, a preliminary sketch, and a fine-tuned final architecture.
Browse libraryAI / ML
Modern ML & LLM engineering
From classical ML foundations to LLM systems — the concepts ML, MLE, and applied-AI interviews probe, each with intuition and tradeoffs.
Browse libraryContext Engineering
Designing what the model sees
The discipline of assembling the right context for LLMs and agents — prompting patterns, retrieval, memory, tool use, and evaluation.
Browse libraryCAD & Mechanical Design
Parametric modeling & manufacturing intent
Core competencies for mechanical-design and CAD interviews — modeling discipline, tolerancing, assemblies, and design-for-manufacture.
Browse libraryMock Interview
Round-by-round rehearsal
Every interview round as a mode — open one for format, sample questions, a model-answer walkthrough, scoring rubric, follow-ups, and a checklist.
Browse libraryAssessments
Take-homes & timed evals
Online assessments and take-homes by format — each with a sample task, a solution approach, and timing tactics.
Browse libraryNon-technical
Behavioral, business & communication
The human side of interviews — behavioral frameworks, business judgment, and communication skills that decide close calls.
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