An experiment in fully hermetic, but also self-installing nix based hermetic bazel build.

The build rules at https://github.com/tweag/rules_nixpkgs allow bazel to bring in dependencies from nixpkgs. But, it requires having a /nix/store on your machine, which in turn means you need to have a pre-existing system-wide nix installation.

This repository goes one step further: bazel will instantiate a bazel-specific nix store and pull in the appropriate dependencies from nixpkgs. This means that you will not need to install nix in order to use the packages from nixpkgs.

This example repo adds the dir //tools to an existing rules_nixpkgs example, which makes a stand-alone and ephemeral nix installation in your bazel cache, and prepares all dependencies for compilation. It then builds a hello world app.

1. install bazelisk, name it bazel
2. try: bazel run :hello

The actual reusable set of bazel local nix rules is at: https://github.com/filmil/bazel_local_nix.

Original README.md below. From https://github.com/tweag/rules_nixpkgs/tree/master/examples/flakes

The example is generating a local nixpkgs repository using the flakes.lock file already present on flakes projects.

The nix package manager should be installed with flakes support enabled.

The local nixpkgs repository can be used by explicitly specifying the generated toolchain.

``bash nix-shell --run "bazel run --crosstool_top=@nixpkgs_config_cc//:toolchain :hello"