TypeScript vs Kotlin/JS: which is better for large frontends?

TypeScript is the better fit for most large JS-based frontends, since it integrates directly with React, Angular, Vue and Next.js without a compilation bridge. Kotlin/JS, JetBrains' compile target for Kotlin, is usually chosen when a team wants to share business logic across Android, iOS and web through Kotlin Multiplatform (KMP).

How do TypeScript and Kotlin/JS compare on a large frontend?

When does TypeScript fit a large frontend?

Teams building a frontend-only or JS-first stack benefit from direct compatibility with React, Vue, Angular and Next.js, plus the npm library ecosystem without an interop layer.

Its type system also scales with team size, since large codebases can enforce contracts across modules without introducing a second language runtime.

When does Kotlin/JS fit better?

Kotlin/JS fits when a company already maintains Android or iOS apps in Kotlin and wants one codebase for business logic across platforms through Kotlin Multiplatform.

It also suits teams standardized on IntelliJ-based tooling, where sharing validation, networking or state logic between mobile and web outweighs a smaller JS package ecosystem.

Which one should a large frontend team choose?

A frontend built primarily for the browser, staffed from the JS/TS talent pool, is better served by TypeScript. A frontend that mainly extends an established Kotlin Multiplatform codebase from mobile to web is the case where Kotlin/JS earns its added complexity.