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New Sixteen new practice lessons push four modules past their old ceiling. Postgres: CTEs, chained and recursive CTEs, RANK with PARTITION BY, and LAG for month-over-month change - against real Postgres in your browser. TypeScript: narrowing with in and instanceof, discriminated unions, exhaustiveness with never, generic constraints, and a generic Stack. Math and Physics each gain three advanced rungs, from the quadratic formula to a collision-reconstruction capstone.
New Seven new cheat sheets: JavaScript (array methods, destructuring, async), CSS (flexbox, grid, and the centering recipes), TypeScript (utility types and narrowing), React Hooks (signatures plus which-hook-when), grep & find, systemctl & journalctl, and nginx. The SSH sheet gained rsync, and the Python sheet now covers uv properly.
New Build a Mini UI Framework: the frontend wave's capstone project. In about 120 lines of runnable JavaScript you build the machinery inside React, Vue, and Svelte yourself - a proxy reactivity system, automatic dependency tracking, a virtual DOM, and a diff - then trigger the famous keys bug on purpose and fix it. The magic box, emptied.
New Angular from Zero rounds out the big four: the full-framework deal explained through its modern core - standalone components, signals, dependency injection demystified, and just enough RxJS to be productive without drowning. The NG-numbered errors get their own decoder.
New Svelte from Zero: the framework this site is built with, explained from the compiler up - runes, dead-snapshot debugging, snippets, and why there is no virtual DOM to diff. Eight phases, including a translation table for the older syntax you will meet in the wild.

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Angular from Zero - The Full-Framework Deal What Angular actually is - a complete, TypeScript-first application framework - explained through its modern core: standalone components, signals, dependency injection, and just enough RxJS.
Build a Mini UI Framework - The Magic, Demystified Build the machinery inside React, Vue, and Svelte yourself in ~120 lines of plain JavaScript: a proxy-based reactivity system, effects and computed values, a virtual DOM, and a diff.
Next.js from Zero - React Grows a Server What Next.js adds to React and why - file routing, server components, data fetching, caching - explained from the request up, so the framework stops feeling like magic conventions.