TypeScript in 2025 — is it still worth it for small projects?_

You can get IDE type checking in plain .js files using JSDoc comments and // @ts-check at the top. VS Code reads JSDoc types and gives you autocomplete and error highlighting without a build step. Genuinely viable for small projects.

The 'TypeScript is overhead' argument made more sense in 2018. Today tsc is fast, most tools have first-class TS support, and you can use isolatedModules mode so each file transpiles independently. The DX cost is very low.

TypeScript earns its keep when you need to rename a prop, change a function signature, or restructure a module. The compiler finds every call site. In plain JS you hope your grep is thorough and your tests cover everything.

Under 500 lines: plain JS with JSDoc types is fine. Over 500 lines or involving other contributors: TypeScript. The crossover point where TypeScript pays for itself is lower than people think.