nix: compile deps with the same elixir version

.gitignore

@@ -18,5 +18,6 @@ erl_crash.dump
 
 # nix
 /.direnv
+.pre-commit-config.yaml
 /.elixir_ls
 /result

flake.lock

@@ -1,5 +1,21 @@
 {
   "nodes": {
+    "flake-compat": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1673956053,
+        "narHash": "sha256-4gtG9iQuiKITOjNQQeQIpoIB6b16fm+504Ch3sNKLd8=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "35bb57c0c8d8b62bbfd284272c928ceb64ddbde9",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
     "flake-parts": {
       "inputs": {
         "nixpkgs-lib": "nixpkgs-lib"
@@ -18,6 +34,39 @@
         "type": "github"
       }
     },
+    "flake-root": {
+      "locked": {
+        "lastModified": 1680964220,
+        "narHash": "sha256-dIdTYcf+KW9a4pKHsEbddvLVSfR1yiAJynzg2x0nfWg=",
+        "owner": "srid",
+        "repo": "flake-root",
+        "rev": "f1c0b93d05bdbea6c011136ba1a135c80c5b326c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "srid",
+        "repo": "flake-root",
+        "type": "github"
+      }
+    },
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1685518550,
+        "narHash": "sha256-o2d0KcvaXzTrPRIo0kOLV0/QXHhDQ5DTi+OxcjO8xqY=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "a1720a10a6cfe8234c0e93907ffe81be440f4cef",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
     "gitignore": {
       "inputs": {
         "nixpkgs": [
@@ -40,11 +89,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1688859638,
+        "lastModified": 1690720142,
-        "narHash": "sha256-GyRhX8GlTQqDWx43uBFEYEQ/WKEqDwjzABHxUCatAno=",
+        "narHash": "sha256-GywuiZjBKfFkntQwpNQfL+Ksa2iGjPprBGL0/psgRZM=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "d485da9d0034a72ceb9679c2ab0156c073f66b82",
+        "rev": "3acb5c4264c490e7714d503c7166a3fde0c51324",
         "type": "github"
       },
       "original": {
@@ -72,11 +121,91 @@
         "type": "github"
       }
     },
+    "nixpkgs-stable": {
+      "locked": {
+        "lastModified": 1685801374,
+        "narHash": "sha256-otaSUoFEMM+LjBI1XL/xGB5ao6IwnZOXc47qhIgJe8U=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "c37ca420157f4abc31e26f436c1145f8951ff373",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-23.05",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "pre-commit-hooks-nix": {
+      "inputs": {
+        "flake-compat": "flake-compat",
+        "flake-utils": "flake-utils",
+        "gitignore": [
+          "gitignore"
+        ],
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "nixpkgs-stable": "nixpkgs-stable"
+      },
+      "locked": {
+        "lastModified": 1690743255,
+        "narHash": "sha256-dsJzQsyJGWCym1+LMyj2rbYmvjYmzeOrk7ypPrSFOPo=",
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "rev": "fcbf4705d98398d084e6cb1c826a0b90a91d22d7",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "repo": "pre-commit-hooks.nix",
+        "type": "github"
+      }
+    },
     "root": {
       "inputs": {
         "flake-parts": "flake-parts",
+        "flake-root": "flake-root",
         "gitignore": "gitignore",
-        "nixpkgs": "nixpkgs"
+        "nixpkgs": "nixpkgs",
+        "pre-commit-hooks-nix": "pre-commit-hooks-nix",
+        "treefmt-nix": "treefmt-nix"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
+    "treefmt-nix": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1689620039,
+        "narHash": "sha256-BtNwghr05z7k5YMdq+6nbue+nEalvDepuA7qdQMAKoQ=",
+        "owner": "numtide",
+        "repo": "treefmt-nix",
+        "rev": "719c2977f958c41fa60a928e2fbc50af14844114",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "treefmt-nix",
+        "type": "github"
       }
     }
   },

flake.nix

@@ -2,45 +2,87 @@
   description = "weewx-proxy development environment";
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+
+    # Tools
+
     flake-parts.url = "github:hercules-ci/flake-parts";
 
+    flake-root.url = "github:srid/flake-root";
+
+    treefmt-nix = {
+      url = "github:numtide/treefmt-nix";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+
     gitignore = {
       url = "github:hercules-ci/gitignore.nix";
       inputs.nixpkgs.follows = "nixpkgs";
     };
+
+    pre-commit-hooks-nix = {
+      url = "github:cachix/pre-commit-hooks.nix";
+      inputs.nixpkgs.follows = "nixpkgs";
+      inputs.gitignore.follows = "gitignore";
+    };
   };
 
   outputs = inputs@{ flake-parts, gitignore, ... }:
     flake-parts.lib.mkFlake { inherit inputs; } {
       systems = [ "aarch64-darwin" "x86_64-linux" "aarch64-linux" ];
 
-      perSystem = { pkgs, lib, self', ... }:
+      imports = [
+        inputs.flake-root.flakeModule
+        inputs.treefmt-nix.flakeModule
+        inputs.pre-commit-hooks-nix.flakeModule
+      ];
+
+      perSystem = { pkgs, config, lib, self', ... }:
         let
           pname = "weewx-proxy";
           version = "0.0.1";
 
           erlang = pkgs.beam.interpreters.erlangR26;
-          beamPackages = pkgs.beam.packagesWith erlang;
+          beamPackagesPrev = pkgs.beam.packagesWith erlang;
-          elixir = beamPackages.elixir_1_15;
+          elixir = beamPackagesPrev.elixir_1_15;
+
+          beamPackages = beamPackagesPrev // rec {
+            inherit erlang elixir;
+            hex = beamPackagesPrev.hex.override { inherit elixir; };
+            buildMix = beamPackagesPrev.buildMix.override { inherit elixir erlang hex; };
+            mixRelease = beamPackagesPrev.mixRelease.override { inherit erlang elixir; };
+          };
 
           inherit (pkgs.stdenv) isDarwin;
           inherit (gitignore.lib) gitignoreSource;
         in
         {
-          devShells.default = pkgs.mkShell {
+          treefmt = {
-            packages = (with pkgs; [
+            inherit (config.flake-root) projectRootFile;
-              erlang
+            flakeCheck = false;
-              elixir
 
-              beamPackages.elixir-ls
+            programs = {
-              mix2nix
+              mix-format = {
-              mosquitto
+                enable = true;
-            ]) ++ lib.optionals isDarwin (with pkgs.darwin.apple_sdk.frameworks; [
+                package = elixir;
-              CoreFoundation
+              };
-              CoreServices
-            ]);
 
-            ERL_INCLUDE_PATH = "${erlang}/lib/erlang/usr/include";
+              nixpkgs-fmt.enable = true;
+              shfmt.enable = true;
+            };
+          };
+
+          pre-commit = {
+            check.enable = false;
+
+            settings = {
+              excludes = [ "mix.nix" ];
+
+              hooks = {
+                deadnix.enable = true;
+                statix.enable = true;
+                treefmt.enable = true;
+              };
+            };
           };
 
           packages.default = beamPackages.mixRelease {
@@ -54,6 +96,9 @@
             name = pname;
             tag = "v${version}";
             config = {
+              Env = [
+                "LANG=C.UTF-8"
+              ];
               ExposedPorts = { "4040/tcp" = { }; };
               Entrypoint = [ "${self'.packages.default}/bin/weewx_proxy" ];
               Cmd = [ "start" ];
@@ -61,6 +106,34 @@
           };
 
           apps.default = { type = "app"; program = "${self'.packages.default}/bin/weewx_proxy"; };
+
+          devShells.default = pkgs.mkShell {
+            name = pname;
+
+            nativeBuildInputs = [
+              erlang
+              elixir
+            ] ++ lib.optionals isDarwin (with pkgs.darwin.apple_sdk.frameworks;
+              [
+                CoreFoundation
+                CoreServices
+              ]);
+
+            packages = [
+              beamPackages.elixir-ls
+              pkgs.mix2nix
+              pkgs.mosquitto
+            ];
+
+            inputsFrom = [
+              config.flake-root.devShell
+              config.treefmt.build.devShell
+              config.pre-commit.devShell
+            ];
+
+            ERL_INCLUDE_PATH = "${erlang}/lib/erlang/usr/include";
+            TREEFMT_CONFIG_FILE = config.treefmt.build.configFile;
+          };
         };
     };
 }

mix.nix

@@ -359,5 +359,6 @@ let
       beamDeps = [ ];
     };
   };
-in self
+in
+self