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TypeScript `Map` and `Set` Iteration in 2026: Why `downlevelIteration` Still Breaks Production Builds
November 9, 2026
The downlevelIteration flag controls how TypeScript transpiles Map, Set, and array iteration to older JavaScript. Production builds still break without it because the default transpilation produces index-based loops that fail on iterables. Here's what actually happens and when you must enable it.
React 20 Compiler: Which Hooks It Eliminates, Which It Cannot, and How to Audit Your Codebase Before Upgrading
November 8, 2026
The React Compiler auto-memoizes components and hooks, eliminating most useMemo and useCallback calls. Developers must audit effect dependencies, library compatibility, and exact-identity patterns before migrating.
Claude Code Diff Verification in 2026: How to Make Your Agent Assert Its Own Edits Did Not Break the Build
November 7, 2026
Stop trusting AI edits on faith. Learn how to build post-edit verification hooks that make Claude Code run git diff, tests, and type checks before you ever see the changes, turning agent sessions into self-validating workflows.
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