Why?

If a project build takes 15 minutes, why build it three times and waste your users time? With Cachix you can just easily distribute the binaries.

• You build your software project on your laptop during development.
• Your Continuous Integration builds the project again to verify there are no mistakes.
• Users of your project build it again to use or deploy it.

How?

Nix builds a package in isolation from your system. This ensures that build process is reproducible and doesn’t have undeclared dependencies, so if a package is built on one machine, it will build identically on another machine.

Nix also hashes the inputs before building a package. By querying Cachix with the hash, it's possible to download the binary identified by the hash as a replacement for the build process.

What?

Binary Cache as a Service - Cachix: allows you to create your own binary caches within seconds after you've signed-in:

$ cachix create <name>

and be able to upload binaries to https://<name>.cachix.org with a simple command:

$ nix-build | cachix push <name>

While users of your cache can configure Nix without fiddling with config files:

$ cachix use <name>