Most of us know the Angular compiler as the part of the CLI which builds and type-checks our applications, but this is just one of the many jobs it performs in the Angular ecosystem. Even before we run `ng serve`, the compiler is alive within the Angular Language Service, helping us edit templates in our IDEs. Long before we `yarn install` them, the compiler has processed the libraries we depend on and helped prepare them for publication on NPM. In this talk, we'll examine the design of the Angular compiler, explore the many ways it supports our tooling today, and take a peek at the new Angular Linker system for library compilation and consumption.