Our TypeScript project is ~20K SLOC. It compiles in roughly (I haven't measured exactly) the same amount of time it takes to compile 100 SLOC.

Since the Typescript compiler itself is > 2MB of minified js, it doesn't surprise me that compiling any TS has at least a second overhead.

What's more important to me is that:

- The compiler performance scales as the codebase increases in size.

- Incremental builds are fast. (ie the -watch option).

So far I have found both to be true. Incremental builds take < .5 sec on my laptop. That means I get a cute red-squiggly in Visual Studio in a convenient amount of time. Ultimately, that's half the reason for using TS in the first place; if it didn't improve our productivity, we wouldn't be using it.