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Strict Mode Isn't Enough: Using TypeScript's New Variance Annotations to Catch Subtle Generic Bugs
June 26, 2026
Most generic type bugs stem from variance issues that strict mode doesn't catch. TypeScript's new 'in' and 'out' annotations finally give developers explicit control over covariance and contravariance in generic parameters.
How TypeScript 5.7's --module nodenext Changes Are Breaking Legacy Express Apps (and How to Fix Them)
June 25, 2026
TypeScript 5.7's stricter --module nodenext enforcement breaks three critical patterns in Express apps. Here's what changed and how to migrate without rewriting your entire codebase.
TypeScript Isolated Declarations: Real-World Performance Gains in Monorepo Build Times
June 24, 2026
Most monorepo build bottlenecks stem from sequential declaration file generation. The --isolatedDeclarations flag enables parallel .d.ts emit with 3x to 15x faster builds. Here's how to configure it and migrate your codebase without breaking changes.
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