A fast rust tool to check availability of your entire system in caches. It so to speak "checks the weather" before going to update. Heavily inspired by guix weather.

cli eupl-1.2 lix nix nixos rust

Find a file

Christina Sørensen 4324ee17e8 All checks were successful conventional commits / conventional commits (push) Successful in 6s Details build / run (push) Successful in 4m39s Details check / run (push) Successful in 49s Details merge: 'issue-14' from email		2024-10-27 15:36:05 +01:00
.config	fix: the small things	2024-09-11 09:29:02 +02:00
.forgejo	fix: use our own forgejo actions repo	2024-09-09 07:50:42 +02:00
.github	ci: removed unused cheks, add funding for github	2024-09-05 21:02:09 +02:00
crates	build(deps): reqwest 0.11 -> 0.12	2024-10-27 15:31:55 +01:00
LICENSES	docs: readme headers, code of conduct	2024-09-05 08:50:47 +02:00
.envrc	feat: flake + lix	2024-09-05 07:32:31 +02:00
.gitignore	feat: flake + lix	2024-09-05 07:32:31 +02:00
.rustfmt.toml	build: change rust tabwidth	2024-09-06 11:24:30 +02:00
.versionrc	build: add convco config with merge type	2024-09-05 10:26:56 +02:00
Cargo.lock	build(deps): reqwest 0.11 -> 0.12	2024-10-27 15:31:55 +01:00
Cargo.toml	chore(release): cargo `v0.0.4`	2024-09-13 07:19:58 +02:00
CODE_OF_CONDUCT.md	docs: readme headers, code of conduct	2024-09-05 08:50:47 +02:00
CONTRIBUTING.md	docs: add CONTRIBUTING.md	2024-09-05 10:07:11 +02:00
deny.toml	ci: allow own license	2024-09-07 11:43:47 +02:00
flake.lock	build(deps): bump `flake.lock`	2024-09-06 05:10:38 +02:00
flake.nix	fix: the small things	2024-09-11 09:29:02 +02:00
justfile	build: add basic changelog gen	2024-09-06 05:08:33 +02:00
LICENSE.txt	feat: flake + lix	2024-09-05 07:32:31 +02:00
README.md	docs: correct readme h1	2024-09-05 10:11:53 +02:00
REUSE.toml	build: add convco config with merge type	2024-09-05 10:26:56 +02:00

README.md

Nix Weather - Check Cache Availablility of NixOS Configurations

A fast rust tool to check availability of your entire system in caches. It so to speak "checks the weather" before going to update. Heavily inspired by guix weather.

Usage

Note

Currently, nix-weather only has first-class support for flakes.

General usage would be like this:

nix-weather --name myhost --config ~/git/my-nixos-config

Here, we specify the name of the host, as specified at the flake output nixosConfiguration, and a path to the NixOS configuration flake.

How It Works

The basic idea is that we construct a set of all requisites to build the top-level of a NixOS configuration, and then query Nix cache(s) for the narinfo. By doing this in a high concurrency, parallel task runner (i.e. tokio async runtime), and only querying the headers for status codes, we can reach impressive speeds, typically around 45~ network time.

One of the biggest limiting factors regarding speed is building the config.system.toplevel, and finding the necessary requisites with nix-store. Caching the requisites is a future goal, so that we only have to build the toplevel, and then match against its derivation in cache, which should cut down the nix part of the runtime by ~80%.

Contributing

For information on contributing, please see CONTRIBUTING.md.