2024-05-25

1 files changed, 118 insertions, 112 deletions

diff --git a/modules/common/nix.nix b/modules/common/nix.nix
index c03c1b1..6c5bd18 100644
--- a/modules/common/nix.nix
+++ b/modules/common/nix.nix
@@ -3,7 +3,6 @@
   inputs,
   lib,
   pkgs,
-  pkgsPr,
   this,
   ...
 }:
@@ -12,142 +11,149 @@ let
   cfg = config.nixfiles.modules.common.nix;
 in
 {
+  imports = with inputs.srvos.nixosModules; [
+    mixins-nix-experimental
+    mixins-trusted-nix-caches
+  ];
+
   options.nixfiles.modules.common.nix.allowedUnfreePackages = mkOption {
     description = "A list of allowed unfree packages.";
     type = with types; listOf str;
     default = [ ];
   };
 
-  config = {
-    _module.args =
-      let
-        importNixpkgs =
-          nixpkgs:
-          import nixpkgs {
-            inherit (config.nixpkgs) config;
-            inherit (this) system;
-          };
-      in
-      rec {
-        pkgsLocal = importNixpkgs "${config.my.home}/src/nixpkgs"; # Impure!
-        pkgsMaster = importNixpkgs inputs.nixpkgs-master;
-        pkgsStable = importNixpkgs inputs.nixpkgs-stable;
-        pkgsRev =
-          rev: hash:
-          importNixpkgs (
-            pkgs.fetchFromGitHub {
-              owner = "NixOS";
-              repo = "nixpkgs";
-              inherit rev hash;
-            }
-          );
-        pkgsPr = pr: pkgsRev "refs/pull/${toString pr}/head";
+  config =
+    let
+      useNixpkgs =
+        nixpkgs:
+        import nixpkgs {
+          inherit (config.nixpkgs) config;
+          inherit (this) system;
+        };
+
+      pkgsLocal = useNixpkgs "${config.my.home}/src/nixpkgs"; # Impure!
+      pkgsMaster = useNixpkgs inputs.nixpkgs-master;
+      pkgsStable = useNixpkgs inputs.nixpkgs-stable;
+      pkgsRev =
+        rev: hash:
+        useNixpkgs (
+          pkgs.fetchFromGitHub {
+            owner = "NixOS";
+            repo = "nixpkgs";
+            inherit rev hash;
+          }
+        );
+      pkgsPr = pr: pkgsRev "refs/pull/${toString pr}/head";
+    in
+    {
+      _module.args = {
+        inherit
+          pkgsLocal
+          pkgsMaster
+          pkgsStable
+          pkgsRev
+          pkgsPr
+          ;
+      };
+
+      hm = {
+        # Used primarily in conjunction with the "nixfiles" script.
+        home.file.".nix-defexpr/default.nix".text =
+          let
+            hostname = strings.escapeNixIdentifier this.hostname;
+          in
+          optionalString this.isHeadful ''
+            let
+              self = builtins.getFlake "nixfiles";
+              configurations = self.nixosConfigurations;
+              local = configurations.${hostname};
+            in rec {
+              inherit self;
+              inherit (self) inputs lib;
+              inherit (lib) my;
+              this = my.configurations.${hostname};
+              inherit (local) config;
+              inherit (local.config.system.build) toplevel vm vmWithBootLoader manual;
+              pretty = expr: lib.trace (lib.generators.toPretty {} expr) {};
+            } // configurations // local._module.args
+          '';
+
+        programs.bash.shellAliases.nix = "nix --verbose --print-build-logs";
       };
 
-    hm = {
-      # Used primarily in conjunction with the "nixfiles" script.
-      home.file.".nix-defexpr/default.nix".text =
+      nix =
         let
-          hostname = strings.escapeNixIdentifier this.hostname;
+          notSelfInputs = filterAttrs (n: _: n != "self") inputs;
         in
-        optionalString this.isHeadful ''
-          let
-            self = builtins.getFlake "nixfiles";
-            configurations = self.nixosConfigurations;
-            local = configurations.${hostname};
-          in rec {
-            inherit self;
-            inherit (self) inputs lib;
-            inherit (lib) my;
-            this = my.configurations.${hostname};
-            inherit (local) config;
-            inherit (local.config.system.build) toplevel vm vmWithBootLoader manual;
-            pretty = expr: lib.trace (lib.generators.toPretty {} expr) {};
-          } // configurations // local._module.args
-        '';
-
-      programs.bash.shellAliases.nix = "nix --verbose --print-build-logs";
-    };
+        {
+          daemonCPUSchedPolicy = "idle";
+          daemonIOSchedClass = "idle";
+          daemonIOSchedPriority = 7;
 
-    nix =
-      let
-        notSelfInputs = filterAttrs (n: _: n != "self") inputs;
-      in
-      {
-        daemonCPUSchedPolicy = "idle";
-        daemonIOSchedClass = "idle";
-        daemonIOSchedPriority = 7;
-
-        settings = {
-          # https://nixos.org/manual/nix/unstable/contributing/experimental-features.html#currently-available-experimental-features
-          # https://github.com/NixOS/nix/blob/master/src/libutil/experimental-features.cc
-          experimental-features = concatStringsSep " " [
-            "flakes"
-            "nix-command"
-            "recursive-nix"
-            "repl-flake"
-          ];
+          settings = {
+            keep-derivations = if this.isHeadful then "true" else "false";
+            keep-outputs = if this.isHeadful then "true" else "false";
 
-          keep-derivations = if this.isHeadful then "true" else "false";
-          keep-outputs = if this.isHeadful then "true" else "false";
+            warn-dirty = false;
 
-          flake-registry = "${inputs.flake-registry}/flake-registry.json";
+            keep-going = true;
 
-          warn-dirty = false;
+            substituters = [
+              "https://azahi.cachix.org"
+              "https://nix-community.cachix.org"
+            ];
 
-          keep-going = true;
+            trusted-substituters = [ "https://azahi.cachix.org" ];
+            trusted-public-keys = [ "azahi.cachix.org-1:2bayb+iWYMAVw3ZdEpVg+NPOHCXncw7WMQ0ElX1GO3s=" ];
 
-          substituters = [
-            "https://azahi.cachix.org"
-            "https://nix-community.cachix.org"
-          ];
-          trusted-public-keys = [
-            "azahi.cachix.org-1:2bayb+iWYMAVw3ZdEpVg+NPOHCXncw7WMQ0ElX1GO3s="
-            "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
-          ];
+            trusted-users = [
+              "root"
+              my.username
+            ];
+          };
 
-          trusted-users = [
-            "root"
-            my.username
+          nixPath = mapAttrsToList (n: v: "${n}=${v}") notSelfInputs ++ [
+            "nixfiles=${config.my.home}/src/nixfiles"
           ];
+
+          registry = mapAttrs (_: flake: { inherit flake; }) notSelfInputs // {
+            nixfiles.flake = inputs.self;
+          };
         };
 
-        nixPath = mapAttrsToList (n: v: "${n}=${v}") notSelfInputs ++ [
-          "nixfiles=${config.my.home}/src/nixfiles"
+      nixpkgs = {
+        config.allowUnfreePredicate = p: elem (getName p) cfg.allowedUnfreePackages;
+
+        overlays = with inputs; [
+          self.overlays.default
+          (_: _: {
+            # Global PR package overrides go here. Example:
+            # ```
+            # inherit (pkgsPr 309018 "sha256-x3ATxjrTVdaX5eo9P6pz+8/W6D2TNYzvjZpOBa3ZRI8=") endlessh-go;
+            # ```
+          })
         ];
+      };
 
-        registry = mapAttrs (_: flake: { inherit flake; }) notSelfInputs // {
-          nixfiles.flake = inputs.self;
+      environment = {
+        localBinInPath = true;
+        defaultPackages = [ ];
+        systemPackages =
+          with pkgs;
+          optionals this.isHeadful [
+            nix-top
+            nix-tree
+            nixfiles
+          ];
+        variables = {
+          NIXFILES = "${config.my.home}/src/nixfiles";
+          NIX_SHELL_PRESERVE_PROMPT = "1";
         };
       };
 
-    nixpkgs = {
-      config.allowUnfreePredicate = p: elem (getName p) cfg.allowedUnfreePackages;
-
-      overlays = with inputs; [
-        self.overlays.default
-        (_: _super: {
-          inherit (pkgsPr 309018 "sha256-x3ATxjrTVdaX5eo9P6pz+8/W6D2TNYzvjZpOBa3ZRI8=") endlessh-go;
-        })
-      ];
-    };
-
-    environment = {
-      localBinInPath = true;
-      defaultPackages = mkForce [ ];
-      systemPackages =
-        with pkgs;
-        optionals this.isHeadful [
-          nix-top
-          nix-tree
-          nixfiles
-        ];
-      sessionVariables = {
-        NIXFILES = "${config.my.home}/src/nixfiles";
-        NIX_SHELL_PRESERVE_PROMPT = "1";
+      system = {
+        # HACK This lets `nix flake check` to pass.
+        stateVersion = if hasAttr "stateVersion" this then this.stateVersion else trivial.release;
       };
     };
-
-    system.stateVersion = with builtins; head (split "\n" (readFile "${inputs.nixpkgs}/.version"));
-  };
 }