Turbopack

Turbopack, Next.js's replacement bundler, complains about valid TypeScript code and struggles to understand `:global` in CSS modules. Despite these issues, it remains unstable and not production-ready.

Build performance remains a major concern with 8,511 GitHub issues. Despite being a core Next.js promise, developers struggle with Turbopack, Babel, and webpack optimization. Experimental features often break existing setups, and slow builds cascade to affect all feature delivery timelines.