Sourcemaps are technically already implemented, but not for bundled dependencies. Initially, it was a 30% drop, but I made it use lots of SIMD and that compensated a lot. When you use Bun's runtime, it transpiles every file (including non-TypeScript files) and generates an in-memory sourcemap so that error messages have useful line/column numbers. Bun's fast startup time is very much in spite of things like this.

Minification will likely make it faster because there will be less code to print (see https://twitter.com/evanwallace/status/1396304029840396290). Many of the syntax compression and small optimizations like ("foo" + " " + "bar") becoming "foo bar" are implemented already, but not the whitespace removal

It might have an impact on bundling performance overall because that will involve an extra pass to more correctly handle `export * as from`, which isn't as important when used with the runtime (since that can happen at runtime)