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Cheat sheets.
Printable, interview-focused reference cards — the core syntax, behaviour, and gotchas worth a final glance before you walk in. Each one prints clean to a PDF.
JavaScript & TypeScript
Core language behaviour, async, and the type-system bits that trip people up in interviews.
4 sections →React
Hooks rules, rendering, and the performance questions interviewers love.
4 sections →Node.js
The event loop, streams, and backend patterns that come up in system questions.
4 sections →SQL
Joins, aggregation, indexing, and the query questions that show up in most data rounds.
4 sections →