salsa

A generic framework for on-demand, incrementalized computation.

Obligatory warning

Very much a WORK IN PROGRESS at this point. Ready for experimental use
but expect frequent breaking changes.

Credits

This system is heavily inspired by adapton, glimmer, and rustc's query
system. So credit goes to Eduard-Mihai Burtescu, Matthew Hammer,
Yehuda Katz, and Michael Woerister.

Key idea

The key idea of salsa is that you define your program as a set of
queries. Every query is used like function K -> V that maps from
some key of type K to a value of type V. Queries come in two basic
varieties:

• Inputs: the base inputs to your system. You can change these
  whenever you like.
• Functions: pure functions (no side effects) that transform your
  inputs into other values. The results of queries are memoized to
  avoid recomputing them a lot. When you make changes to the inputs,
  we'll figure out (fairly intelligently) when we can re-use these
  memoized values and when we have to recompute them.

Want to learn more?

To learn more about Salsa, try one of the following:

• read the heavily commented examples;
• check out the Salsa book;
  • 中文版
• watch one of our videos.

Getting in touch

The bulk of the discussion happens in the issues
and pull requests,
but we have a zulip chat as well.