8 posts tagged with "under-the-hood"

Pants balances release velocity and end-user stability via judicious use of deprecation cycles. Experimental backends are a way to get quick feedback on new functionality, before "graduating" it to the formal deprecation policy. Experimental features are still well-supported, and not to be feared!

Unlike earlier build systems, Pants v2 automatically infers your code's internal and external dependencies. And it does this at the file level, so that you get optimal invalidation, caching, and concurrency performance without having to manually create and maintain mountains of BUILD file metadata.

How we worked around some quirks and limitations of GitHub Actions to skip CI jobs that aren't necessary in certain scenarios, without breaking branch protection rules that normally require those CI jobs to succeed.

We ended up setting up a self-hosted GitHub Actions runner, on a hosted Mac M1. Getting the machine itself up and running was easy, thanks to MacStadium's simple, effective UX. But setting up the GHA runner on it was a little trickier, for a couple of reasons...

Fast incremental re-builds are critical in large codebases and monorepos. Thanks to deep support for cancellation and a side-effect free execution model, Pants is able to further reduce re-build latency by speculatively re-executing work.

Scalable build tools have historically meant a significant boilerplate burden.

But it doesn't have to be that way! Pants v2 supports all of the caching, concurrency, and introspection you need to scale your repository, with significantly less boilerplate, thanks to… Dependency inference!