Lesson 20 / 30

SWC: The Speed Alternative

Why SWC is 10-50x faster and when to migrate.

Rust vs JavaScript: performance gap

SWC is written in Rust, compiled to native code. Babel is interpreted JavaScript. For large codebases, SWC often transpiles 10-50x faster, making builds much quicker.

When to use SWC over Babel

Use SWC for large projects, monorepos, or if build times exceed 30 seconds. Use Babel if you need specific plugins not yet in SWC or prefer JavaScript tooling.

SWC is the default in Next.js 13+

Vercel switched Next.js to SWC by default. If you use Next.js, SWC is already configured; you benefit from speed automatically.

Monitoring build performance gains

When switching to SWC, expect 3-10 second build time reductions for typical projects. Log build times before and after to validate improvement.