yarr: use pre-built binary instead of building from source

Building yarr from source (Rust) takes ~5+ min and times out the
config-nixos CI runner (3h limit) when combined with the full
perlis+wilkes+relay flake check. Use the pre-built x86_64-linux binary
from GitHub releases instead — fast fetch, no Rust toolchain needed.

Removes the rust-nixpkgs flake input (no longer needed).

flake.nix

@@ -12,14 +12,10 @@
 
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
-    # Newer nixpkgs for yarr: the pinned nixpkgs has rustc 1.95 but yarr
-    # needs 1.97.1. Bumping the main nixpkgs input breaks aioimaplib
-    # (email server dep), so use a separate input just for yarr's rust.
-    rust-nixpkgs.url = "github:NixOS/nixpkgs/0e251e24a4f24e036a084b6b4b2d2491af4167f4";
   };
 
   outputs =
-    { self, nixpkgs, rust-nixpkgs, ... }:
+    { self, nixpkgs, ... }:
     let
       supportedSystems = [
         "x86_64-linux"
@@ -40,10 +36,7 @@
             inherit system;
             overlays = [ self.overlays.default ];
           };
-          # yarr needs rustc 1.97.1; the main nixpkgs input only has 1.95.
+          mcpPackages = import ./packages { inherit pkgs; };
-          # Build its rust toolchain from the newer rust-nixpkgs input.
-          rustPkgs = import rust-nixpkgs { inherit system; };
-          mcpPackages = import ./packages { inherit pkgs rustPkgs; };
         in
         mcpPackages // {
           default = pkgs.symlinkJoin {
@@ -60,8 +53,7 @@
             inherit system;
             overlays = [ self.overlays.default ];
           };
-          rustPkgs = import rust-nixpkgs { inherit system; };
+          mcpPackages = import ./packages { inherit pkgs; };
-          mcpPackages = import ./packages { inherit pkgs rustPkgs; };
         in
         {
           default = pkgs.mkShell {

packages/default.nix

@@ -1,4 +1,4 @@
-{ pkgs, rustPkgs ? pkgs }:
+{ pkgs }:
 
 {
   manim-mcp-server = pkgs.callPackage ./manim-mcp-server/package.nix { };
@@ -28,6 +28,6 @@
   navidrome-mcp = pkgs.callPackage ./navidrome-mcp/package.nix { };
   ovhcloud-mcp = pkgs.callPackage ./ovhcloud-mcp/package.nix { };
   slskd-mcp = pkgs.callPackage ./slskd-mcp/package.nix { };
-  yarr = rustPkgs.callPackage ./yarr/package.nix { };
+  yarr = pkgs.callPackage ./yarr/package.nix { };
   # example-mcp-server = pkgs.callPackage ./example-mcp-server/package.nix { };
 }

packages/yarr/package.nix

@@ -1,31 +1,29 @@
 {
   lib,
-  rustPlatform,
+  stdenv,
-  fetchFromGitHub,
+  fetchzip,
 }:
 
-rustPlatform.buildRustPackage rec {
+stdenv.mkDerivation rec {
   pname = "yarr";
   version = "2.2.2";
 
-  src = fetchFromGitHub {
+  src = fetchzip {
-    owner = "dinglebear-ai";
+    url = "https://github.com/dinglebear-ai/yarr/releases/download/v${version}/yarr-x86_64.tar.gz";
-    repo = "yarr";
+    hash = lib.fakeHash;
-    rev = "15a599bab38a";
-    hash = "sha256-PlD2NYK06rVdKirUq2dw04WL9yFrM2TB1d67Weero0k=";
   };
 
-  cargoHash = "sha256-e89uYPLqwhh1epedUvVEDTT4y35nuwLWlco4AVvKoK4=";
+  installPhase = ''
-
+    mkdir -p $out/bin
-  # The cargo test phase hangs (0% CPU, no rustc procs) — likely a test
+    cp yarr $out/bin/
-  # blocking on network. Skip tests; we only need the binary.
+    chmod +x $out/bin/yarr
-  doCheck = false;
+  '';
 
   meta = with lib; {
     description = "Rust MCP server for media automation fleets - Sonarr, Radarr, Prowlarr, Jellyfin, SABnzbd, qBittorrent, Plex";
     homepage = "https://github.com/dinglebear-ai/yarr";
     license = licenses.agpl3Only;
     mainProgram = "yarr";
-    platforms = platforms.all;
+    platforms = [ "x86_64-linux" ];
   };
 }