Thematic collection

2 · 10-day crash course

Use when the loop is soon. One pattern family, one LLD classic hub, one HLD warm-up, STAR, company guide.

  1. Backend interview prep plan A Lattice master plan for backend loops: round map, skills checklist, must-know topics, 6-week and 2-week schedules, mock rubrics, day-of checklists, and failure modes — with links into every Lattice series.
  2. Backend interview checklist Backend interview mastery checklist: coding patterns, LLD classics with concurrency, HLD building blocks and tech tradeoffs, behavioral bars, company overlays, and an honest pass/fail gate.
  3. Interview cheat sheet One-page interview crib: coding patterns, LLD 35-min spine, HLD delivery, STAR behavioral, and offer negotiation scripts — skim before each round.
  4. Coding interview roadmap A clear map of DSA patterns for interviews — what to learn, in what order, and which Lattice posts to open for templates.
  5. Arrays & hash maps When to use hash maps, frequency counting, Two Sum family, prefix+hash, and the sort vs map tradeoff — with Python and Java templates.
  6. Two pointers & sliding windows When each pattern applies, how the window moves, and worked traces for pair-sum and longest substring — more explanation than a bare template.
  7. Binary search Why binary search works, the invariant you must say out loud, lower_bound templates, and search-on-answer with a full shipping-capacity walkthrough.
  8. LLD delivery framework (35 min) Step-by-step LLD interview pacing: requirements, entities, class design, implementation, and extensibility — with Tic-Tac-Toe as the running example.
  9. Design a parking lot Parking lot LLD: motorcycle/car/large spots, ticket on enter, hourly fee in cents with round-up, relational occupancy set, enter/exit APIs, verification, and multi-floor / concurrency extensions.
  10. Design a rate limiter (LLD) In-memory API gateway rate limiter LLD: per-endpoint configs, LimiterFactory + Strategy, Token Bucket and Sliding Window Log, RateLimitResult, then concurrency, hot config, and memory eviction as extensions.
  11. System design delivery framework A repeatable structure for system design interviews — requirements, entities, API, high-level design, deep dives — built to stop the most common failure mode: running out of time before you deliver a working system.
  12. Design a URL shortener Junior-friendly Bit.ly walkthrough: requirements, entities, API, create + redirect flows, 301 vs 302, unique short codes (hash vs counter vs batching), caching, read/write split, and what interviewers expect at each level.
  13. Design a rate limiter Token bucket vs sliding window, distributed enforcement, and where to place limits — worked through Tatkal-style booking quotas end to end.
  14. Design a notification system Full HLD: notification platform for push/email/SMS — campaigns, preferences, durable queues, priority isolation for OTPs, and best-effort dedup under 5k/s surges.
  15. STAR answers that stick A practical STAR playbook for staff backend interviews — minute-by-minute timing, We vs I calibration, real vs fake metrics, full samples (including incident + mentoring), story-bank mapping, and a failures checklist.
  16. Amazon SWE interview guide Staff-focused Amazon guide: L5 vs L6 loop deltas, OA skip, phone-screen gate, OOD/project deep-dive, dedicated Bar Raiser, LPs in every round, and design as the make-or-break signal.
  17. Java & Spring Boot code review bible (staff) The Lattice bible for Java/Spring Boot code review and staff bug-bash interviews: Spring Security, JPA/transactions, WebClient/RestTemplate networking, Kafka/async outbox & DLQ, API idempotency — with smell/fix samples, severity ladder, and timed drills.
  18. Java code smells — examples & fixes (staff / principal) Staff and principal Java code-smell catalog with real-world smell/fix samples: money and time, concurrency and lost updates, collections, resources and @Async, nullability, God services, Spring transaction boundaries, observability, and platform guardrails.

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