# nix-community/fenix

Rust toolchains and rust-analyzer nightly for Nix [maintainers=@figsoda, @eureka-cpu]

Repository: https://github.com/nix-community/fenix
Canonical: https://ross.abutalabs.com/products/nix-community-fenix
Language: Nix
License: MPL-2.0
License Family: copyleft
Topics: nix, rust, nightly, overlay, flakes, flake
Last push: 2026-09-02T12:24:37+00:00

## Health v2 (maintenance only)
Score: 77/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 100, release rhythm 35, longevity 100
- inputs: {"age_days": 2069, "days_push": 0, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1115, forks 67 (observed 2026-09-03T02:15:15.542096+00:00)

## What it is
Fenix is a Nix flake and overlay that provides Rust toolchains (minimal, default, complete, and latest nightly profiles) and nightly rust-analyzer builds as Nix packages. It serves as a declarative replacement for rustup and the nixpkgs-mozilla Rust overlay.

## Use cases
- install rust toolchains declaratively with nix flakes
- replace rustup with nix-managed rust toolchains
- get nightly rust-analyzer for vscode
- pin a specific rust toolchain version in a nix devshell
- use rust nightly toolchains in nixos configuration
- set up reproducible rust development environment with nix

## When to choose
- you use Nix and want declarative, reproducible Rust toolchain management
- you need nightly Rust or nightly rust-analyzer versions
- you want per-project toolchain pinning without rustup
- you want to replace nixpkgs-mozilla's rust overlay

## When to avoid
- you don't use the Nix package manager
- you prefer rustup's simple imperative toolchain switching
- you need Windows toolchain binaries (binary cache covers darwin and linux only)

## Facets
- artifact type: infra-config
- maturity: active
- function: build-tool, package-manager, developer-tools
- domain: developer-tools, programming-languages
- platform: cli, cross-platform
- tags: nix, nix-flakes, rust-toolchain, rustup-replacement, rust-analyzer, nightly, overlay, command-line, linux, macos

## Member repositories
- nix-community/fenix (main) score 77

## Provenance
- Observed fields: from GitHub, fetched 2026-09-03T02:15:15.542096+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T06:43:27.994561+00:00, confidence not recorded.
  - readme: https://github.com/nix-community/fenix (fetched 2026-09-03T02:15:15.542096+00:00, sha 92ddf1464767)
- Data as of 2026-08-30T08:39:29.467469+00:00.