Cheat Sheets
Free quick-reference sheets for technical interviews. Skim before the loop, defend in the room.
Big-O Reference
Time and space complexity for the data structures, sorting algorithms, and search routines that show up in coding interviews. Skim the row, remember the row, defend the row in an interview.
Interview Patterns
The recurring shapes - sliding window, two pointers, fast/slow, BFS/DFS, backtracking, DP, divide & conquer, binary search variants, union-find, topological sort. Each entry: when to reach for it, the template, complexity, and which classic problems use it.
Design Tradeoffs
The recurring forks in system design interviews. CAP, PACELC, sync vs async, push vs pull, SQL vs NoSQL, sharding shapes, consistency models, cache strategies, idempotency, and rate limiting. For each, the options and when to choose each.
Unix Essentials
Filesystem layout, the commands you actually use (find / grep / awk / sed / xargs), processes and signals, networking, permissions, basic shell scripting, and a vi survival kit.
How these sheets work
Cheat sheets are not a substitute for working the problems. They are the last review you do the night before, and the reference you grep during practice. Each sheet is structured for fast scanning - tables for the things that have a single right answer (Big-O, signal numbers, octal modes), prose for the things that need defending (tradeoffs).
All four sheets are free. Practice the patterns after you skim them - reading is the floor.