Reformat all projects; switch to overlay format

README.md

@@ -35,8 +35,7 @@ Once your preferred template has been initialized, you can use the provided shel
 | [Elixir]                 | [`elixir`](./elixir/)     |
 | [Elm]                    | [`elm`](./elm/)           |
 | [Gleam]                  | [`gleam`](./gleam/)       |
-| [Go] 1.17                | [`go1_17`](./go1.17/)     |
+| [Go]                     | [`go`](./go/)             |
-| [Go] 1.18                | [`go1_18`](./go1.18/)     |
 | [Hashicorp] tools        | [`hashi`](./hashi/)       |
 | [Java]                   | [`java`](./java/)         |
 | [Kotlin]                 | [`kotlin`](./kotlin/)     |
@@ -96,15 +95,9 @@ The sections below list what each template includes. In all cases, you're free t
 
 - [Gleam] 0.22.1
 
-### [`go1.17`](./go1.17/)
+### [`go`](./go/)
 
-- [Go] 1.17
+- [Go] 1.19
-- Standard Go tools ([goimports], [godoc], and others)
-- [golangci-lint]
-
-### [`go1.18`](./go1.18/)
-
-- [Go] 1.18
 - Standard Go tools ([goimports], [godoc], and others)
 - [golangci-lint]
 

clojure/flake.nix

@@ -6,31 +6,38 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
-        jdk = "jdk17";
+      javaVersion = 17;
-
+      overlays = [
-        config = {
+        (self: super: rec {
-          packageOverrides = p: {
+          jdk = super."jdk${toString javaVersion}";
-            boot = p.boot.override { jdk = p.${jdk}; };
+          boot = super.boot.override {
-            clojure = p.clojure.override { jdk = p.${jdk}; };
+            inherit jdk;
-            leiningen = p.leiningen.override { jdk = p.${jdk}; };
           };
+          clojure = super.clojure.override {
+            inherit jdk;
           };
-
+          leiningen = super.leiningen.override {
-        pkgs = import nixpkgs { inherit config system; };
+            inherit jdk;
-        inherit (pkgs) boot clojure leiningen mkShell;
+          };
+        })
+      ];
+      pkgs = import nixpkgs { inherit overlays system; };
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ boot clojure leiningen ];
-            buildInputs = [ boot clojure leiningen ];
 
         shellHook = ''
-              ${clojure}/bin/clj --version
+          ${pkgs.clojure}/bin/clj --version
         '';
       };
-        };
     });
 }

cue/flake.nix

@@ -6,21 +6,23 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        inherit (pkgs) cue mkShell;
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ cue ];
-            buildInputs = [ cue ];
 
         shellHook = ''
-              ${cue}/bin/cue version
+          ${pkgs.cue}/bin/cue version
         '';
       };
-        };
     });
 }

dhall/flake.nix

@@ -6,22 +6,21 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        dhall = pkgs.dhall;
-
-        inherit (pkgs) mkShell;
-        inherit (pkgs.lib) optionals;
-        inherit (pkgs.stdenv) isLinux;
 
       # Helper function for building dhall-* tools
       mkDhallTools = ls:
         builtins.map (tool: pkgs.haskellPackages."dhall-${tool}") ls;
 
-        # dhall-* tools available only on all platforms
+      dhallTools = mkDhallTools [
-        dhallToolsCommon = mkDhallTools [
         "bash"
         "docs"
         "json"
@@ -31,22 +30,15 @@
         "openapi"
         "toml"
         "yaml"
-        ];
+      ] ++ pkgs.lib.optionals (pkgs.stdenv.isLinux) (mkDhallTools [ "csv" "text" ]); # Linux only
-
-        # dhall-* tools available only on Linux
-        dhallToolsLinux = optionals isLinux (mkDhallTools [ "csv" "text" ]);
-
-        dhallTools = dhallToolsCommon ++ dhallToolsLinux;
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = (with pkgs; [ dhall ]) ++ dhallTools;
-            buildInputs = [ dhall ] ++ dhallTools;
 
         shellHook = ''
-              echo "dhall `${dhall}/bin/dhall --version`"
+          echo "dhall `${pkgs.dhall}/bin/dhall --version`"
         '';
       };
-        };
     });
 }

elixir/flake.nix

@@ -6,32 +6,27 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-
-        inherit (pkgs)
-          darwin gigalixir inotify-tools libnotify mkShell terminal-notifier;
-        inherit (pkgs.beam.packages.erlangR25) elixir elixir_ls;
-        inherit (pkgs.darwin.apple_sdk.frameworks) CoreFoundation CoreServices;
-        inherit (pkgs.lib) optionals;
-        inherit (pkgs.stdenv) isDarwin isLinux;
-
-        linuxDeps = optionals isLinux [ gigalixir inotify-tools libnotify ];
-        darwinDeps = optionals isDarwin [ terminal-notifier ]
-          ++ [ CoreFoundation CoreServices ];
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = (with pkgs; [ elixir ]) ++
-            buildInputs = [ elixir elixir_ls ] ++ linuxDeps ++ darwinDeps;
+          pkgs.lib.optionals (pkgs.stdenv.isLinux) (with pkgs; [ gigalixir inotify-tools libnotify ]) ++ # Linux only
+          pkgs.lib.optionals (pkgs.stdenv.isDarwin) (with pkgs; [ terminal-notifier ]) ++ # macOS only
+          (with pkgs.darwin.apple_sdk.frameworks; [ CoreFoundation CoreServices ]);
 
         shellHook = ''
-              ${elixir}/bin/mix --version
+          ${pkgs.elixir}/bin/mix --version
-              ${elixir}/bin/iex --version
+          ${pkgs.elixir}/bin/iex --version
         '';
       };
-        };
     });
 }

elm/flake.nix

@@ -6,23 +6,23 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        inherit (pkgs) mkShell;
-
-        elm = pkgs.elmPackages.elm;
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = (with pkgs.elmPackages; [ elm ]) ++ (with pkgs; [ elm2nix ]);
-            buildInputs = [ elm ] ++ (with pkgs; [ elm2nix ]);
 
-            shellHook = ''
+        shellHook = with pkgs.elmPackages; ''
           echo "elm `${elm}/bin/elm --version`"
         '';
       };
-        };
     });
 }

gleam/flake.nix

@@ -6,23 +6,23 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        gleamPkg = pkgs.gleam;
-
-        inherit (pkgs) mkShell;
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ gleam ];
-            buildInputs = [ gleamPkg ];
 
         shellHook = ''
-              ${gleamPkg}/bin/gleam --version
+          ${pkgs.gleam}/bin/gleam --version
         '';
       };
-        };
     });
 }

go/flake.nix

@@ -0,0 +1,39 @@
+{
+  description = "A Nix-flake-based Go 1.17 development environment";
+
+  inputs = {
+    flake-utils.url = "github:numtide/flake-utils";
+    nixpkgs.url = "github:NixOS/nixpkgs";
+  };
+
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
+    flake-utils.lib.eachDefaultSystem (system:
+    let
+      goVersion = 19;
+      overlays = [ (self: super: { go = super."go_1_${toString goVersion}"; }) ];
+      pkgs = import nixpkgs { inherit overlays system; };
+    in
+    {
+      devShell = pkgs.mkShellNoCC {
+        buildInputs = with pkgs; [
+          # go 1.17.1 (specified by overlay)
+          go
+
+          # goimports, godoc, etc.
+          gotools
+
+          # https://github.com/golangci/golangci-lint
+          golangci-lint
+        ];
+
+        shellHook = ''
+          ${pkgs.go}/bin/go version
+        '';
+      };
+    });
+}

go1.17/flake.nix

@@ -1,42 +0,0 @@
-{
-  description = "A Nix-flake-based Go 1.17 development environment";
-
-  inputs = {
-    flake-utils.url = "github:numtide/flake-utils";
-    nixpkgs.url = "github:NixOS/nixpkgs";
-  };
-
-  outputs = { self, flake-utils, nixpkgs }:
-    flake-utils.lib.eachDefaultSystem (system:
-      let
-        pkgs = import nixpkgs { inherit system; };
-        goPkg = pkgs.go_1_17;
-
-        inherit (pkgs) mkShellNoCC;
-      in
-      {
-        apps.default = {
-          type = "app";
-          program = "${goPkg}/bin/go";
-        };
-
-        devShells = {
-          default = mkShellNoCC {
-            buildInputs = with pkgs; [
-              # go 1.17.1
-              goPkg
-
-              # goimports, godoc, etc.
-              gotools
-
-              # https://github.com/golangci/golangci-lint
-              golangci-lint
-            ];
-
-            shellHook = ''
-              ${goPkg}/bin/go version
-            '';
-          };
-        };
-      });
-}

go1.18/.envrc

@@ -1 +0,0 @@
-use flake .

go1.18/flake.lock

@@ -1,42 +0,0 @@
-{
-  "nodes": {
-    "flake-utils": {
-      "locked": {
-        "lastModified": 1659877975,
-        "narHash": "sha256-zllb8aq3YO3h8B/U0/J1WBgAL8EX5yWf5pMj3G0NAmc=",
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "rev": "c0e246b9b83f637f4681389ecabcb2681b4f3af0",
-        "type": "github"
-      },
-      "original": {
-        "owner": "numtide",
-        "repo": "flake-utils",
-        "type": "github"
-      }
-    },
-    "nixpkgs": {
-      "locked": {
-        "lastModified": 1660984654,
-        "narHash": "sha256-fDcsh8rm2o8cj+WFL8Y2cAqnsej0UGJa+Sy8U2nFg0Q=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "392c83491dcc21d17ab8ea1f809f8f7bd567a5a3",
-        "type": "github"
-      },
-      "original": {
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "root": {
-      "inputs": {
-        "flake-utils": "flake-utils",
-        "nixpkgs": "nixpkgs"
-      }
-    }
-  },
-  "root": "root",
-  "version": 7
-}

go1.18/flake.nix

@@ -1,42 +0,0 @@
-{
-  description = "A Nix-flake-based Go 1.18 development environment";
-
-  inputs = {
-    flake-utils.url = "github:numtide/flake-utils";
-    nixpkgs.url = "github:NixOS/nixpkgs";
-  };
-
-  outputs = { self, flake-utils, nixpkgs }:
-    flake-utils.lib.eachDefaultSystem (system:
-      let
-        pkgs = import nixpkgs { inherit system; };
-        goPkg = pkgs.go_1_18;
-
-        inherit (pkgs) mkShellNoCC;
-      in
-      {
-        apps.default = {
-          type = "app";
-          program = "${goPkg}/bin/go";
-        };
-
-        devShells = {
-          default = mkShellNoCC {
-            buildInputs = with pkgs; [
-              # go 1.18.3
-              goPkg
-
-              # goimports, godoc, etc.
-              gotools
-
-              # https://github.com/golangci/golangci-lint
-              golangci-lint
-            ];
-
-            shellHook = ''
-              ${goPkg}/bin/go version
-            '';
-          };
-        };
-      });
-}

hashi/flake.nix

@@ -7,16 +7,19 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-
+    in
-        inherit (pkgs)
+    {
-          damon levant mkShell nomad nomad-autoscaler nomad-pack packer
+      devShell = pkgs.mkShell {
-          terraform vault;
+        buildInputs = with pkgs; [
-
-        hashiTools = [
           packer
           terraform
           nomad
@@ -25,22 +28,15 @@
           nomad-pack
           levant
           damon
+          terragrunt
         ];
 
-        relatedTools = with pkgs; [ terragrunt ];
+        shellHook = with pkgs; ''
-      in
-      {
-        devShells = {
-          default = mkShell {
-            buildInputs = hashiTools ++ relatedTools;
-
-            shellHook = ''
           echo "packer `${packer}/bin/packer --version`"
           ${terraform}/bin/terraform --version
           ${nomad}/bin/nomad --version
           ${vault}/bin/vault --version
         '';
       };
-        };
     });
 }

haskell/flake.nix

@@ -6,22 +6,24 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        inherit (pkgs) cabal-install ghc mkShell;
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ cabal-install ghc ];
-            buildInputs = [ cabal-install ghc ];
 
-            shellHook = ''
+        shellHook = with pkgs; ''
           ${ghc}/bin/ghc --version
           ${cabal-install}/bin/cabal --version
         '';
       };
-        };
     });
 }

java/flake.nix

@@ -6,31 +6,37 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
-        jdk = pkgs.jdk17;
+      javaVersion = 17;
 
-        config = {
+      overlays = [
-          packageOverrides = p: {
+        (self: super: rec {
-            gradle = (p.gradle.override { java = jdk; });
+          jdk = super."jdk${toString javaVersion}";
-          };
+          gradle = super.gradle.override {
-        };
-
-        pkgs = import nixpkgs { inherit config jdk system; };
             java = jdk;
-        buildTools = with pkgs; [ ant gradle maven ];
+          };
-        inherit (pkgs) mkShell;
+          maven = super.maven.override {
+            inherit jdk;
+          };
+        })
+      ];
+
+      pkgs = import nixpkgs { inherit overlays system; };
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ gradle jdk maven ];
-            buildInputs = [ java ] ++ buildTools;
 
         shellHook = ''
-              ${java}/bin/java -version
+          ${pkgs.jdk}/bin/java -version
         '';
       };
-        };
     });
 }

kotlin/flake.nix

@@ -6,35 +6,37 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
-        jdk = pkgs.jdk17;
+      javaVersion = 17;
 
-        config = {
+      overlays = [
-          packageOverrides = p: {
+        (self: super: rec {
-            gradle = (p.gradle.override { java = jdk; });
+          jdk = pkgs."jdk${toString javaVersion}";
-
+          gradle = super.gradle.override {
-            kotlin = (p.kotlin.override { jre = jdk; });
+            java = jdk;
           };
+          kotlin = super.kotlin.override {
+            jre = jdk;
           };
+        })
+      ];
 
-        pkgs = import nixpkgs { inherit config system; };
+      pkgs = import nixpkgs { inherit overlays system; };
-        inherit (pkgs) mkShell;
-
-        kotlin = pkgs.kotlin;
-        buildTools = with pkgs; [ gradle ];
-        otherTools = with pkgs; [ gcc ncurses patchelf zlib ];
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ kotlin gradle gcc ncurses patchelf zlib ];
-            buildInputs = [ kotlin ] ++ buildTools ++ otherTools;
 
         shellHook = ''
-              ${kotlin}/bin/kotlin -version
+          ${pkgs.kotlin}/bin/kotlin -version
         '';
       };
-        };
     });
 }

nickel/flake.nix

@@ -6,21 +6,23 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        inherit (pkgs) mkShell nickel;
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ nickel ];
-            buildInputs = [ nickel ];
 
         shellHook = ''
-              ${nickel}/bin/nickel --version
+          ${pkgs.nickel}/bin/nickel --version
         '';
       };
-        };
     });
 }

nim/flake.nix

@@ -6,21 +6,23 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        inherit (pkgs) mkShell nim;
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ nim ];
-            buildInputs = [ nim ];
 
         shellHook = ''
-              ${nim}/bin/nim --version
+          ${pkgs.nim}/bin/nim --version
         '';
       };
-        };
     });
 }

nix/flake.nix

@@ -6,26 +6,27 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-
+    in
-        dhallNix = pkgs.haskellPackages.dhall-nix;
+    {
-
+      devShell = {
-        nixRelatedTools = with pkgs; [
+        buildInputs = with pkgs; [
           cachix
-          dhallNix
           lorri
           niv
           nixfmt
           statix
           vulnix
+          haskellPackages.dhall-nix
         ];
-
+      };
-        inherit (pkgs) mkShell;
-      in
-      {
-        devShells = { default = mkShell { buildInputs = nixRelatedTools; }; };
     });
 }

node/flake.nix

@@ -6,26 +6,30 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
-        nodeOverlay = self: super: rec {
+      overlays = [
+        (self: super: rec {
           nodejs = super.nodejs-18_x;
           pnpm = super.nodePackages.pnpm;
           yarn = (super.yarn.override { inherit nodejs; });
-        };
+        })
-        overlays = [ nodeOverlay ];
+      ];
       pkgs = import nixpkgs { inherit overlays system; };
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = pkgs.mkShell {
         buildInputs = with pkgs; [ node2nix nodejs pnpm yarn ];
 
         shellHook = ''
           echo "node `${pkgs.nodejs}/bin/node --version`"
         '';
       };
-        };
     });
 }

ocaml/flake.nix

@@ -6,24 +6,24 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        inherit (pkgs) mkShell;
-        ocaml = pkgs.ocamlPackages.ocaml;
-        ocamlTools = with pkgs.ocamlPackages;
-          [ dune_3 odoc ] ++ (with pkgs; [ ocamlformat ]);
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ ocaml ocamlformat ] ++
-            buildInputs = [ ocaml ] ++ ocamlTools;
+          (with pkgs.ocamlPackages; [ dune_3 odoc ]);
 
         shellHook = ''
-              ${ocaml}/bin/ocaml --version
+          ${pkgs.ocaml}/bin/ocaml --version
         '';
       };
-        };
     });
 }

opa/flake.nix

@@ -6,23 +6,23 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        inherit (pkgs) conftest mkShell open-policy-agent;
-
-        opaTools = [ conftest open-policy-agent ];
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ open-policy-agent conftest ];
-            buildInputs = opaTools;
 
         shellHook = ''
-              ${open-policy-agent}/bin/opa version
+          ${pkgs.open-policy-agent}/bin/opa version
         '';
       };
-        };
     });
 }

protobuf/flake.nix

@@ -6,22 +6,23 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        inherit (pkgs) buf mkShell protobuf;
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ buf protobuf ];
-            buildInputs = [ buf protobuf ];
 
-            shellHook = ''
+        shellHook = with pkgs; ''
           echo "buf `${buf}/bin/buf --version`"
           ${protobuf}/bin/protoc --version
         '';
       };
-        };
     });
 }

python/flake.nix

@@ -7,29 +7,31 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, mach-nix, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , mach-nix
+    , nixpkgs
+    }:
     flake-utils.lib.eachDefaultSystem (system:
     let
-        pkgs = import nixpkgs { inherit system; };
+      overlays = [
-        inherit (pkgs) mkShell;
+        (self: super: {
-
-        python = pkgs.python311;
-
           machNix = mach-nix.defaultPackage.${system};
+          python = super.python311;
+        })
+      ];
 
-        pythonTools = with pkgs;
+      pkgs = import nixpkgs { inherit overlays system; };
-          [ virtualenv ] ++ (with pkgs.python311Packages; [ pip ]);
-        nixTools = [ machNix ];
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ python machNix virtualenv ] ++
-            buildInputs = [ python ] ++ pythonTools ++ nixTools;
+          (with pkgs.python311Packages; [ pip ]);
 
         shellHook = ''
-              ${python}/bin/python --version
+          ${pkgs.python}/bin/python --version
         '';
       };
-        };
     });
 }

ruby/flake.nix

@@ -6,23 +6,27 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
     flake-utils.lib.eachDefaultSystem (system:
     let
-        pkgs = import nixpkgs { inherit system; };
+      overlays = [
-        inherit (pkgs) mkShell;
+        (self: super: {
-
+          ruby = super.ruby_3_1;
-        ruby = pkgs.ruby_3_1;
+        })
+      ];
+      pkgs = import nixpkgs { inherit overlays system; };
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ ruby ];
-            buildInputs = [ ruby ];
 
         shellHook = ''
-              ${ruby}/bin/ruby --version
+          ${pkgs.ruby}/bin/ruby --version
         '';
       };
-        };
     });
 }

rust/flake.nix

@@ -7,41 +7,48 @@
     rust-overlay.url = "github:oxalica/rust-overlay";
   };
 
-  outputs = { self, flake-utils, nixpkgs, rust-overlay }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    , rust-overlay
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
-        overlays = [ (import rust-overlay) ];
+      overlays = [
+        (import rust-overlay)
+        (self: super: {
+          rustToolchain =
+            let
+              rust = super.rust-bin;
+            in
+            if builtins.pathExists ./rust-toolchain.toml then
+              rust.fromRustupToolchainFile ./rust-toolchain.toml
+            else if builtins.pathExists ./rust-toolchain then
+              rust.fromRustupToolchainFile ./rust-toolchain
+            else
+              rust.stable.latest.default;
+        })
+      ];
 
       pkgs = import nixpkgs { inherit system overlays; };
-
-        inherit (pkgs) mkShell rust-bin;
-        inherit (pkgs.lib) optionals;
-        inherit (pkgs.stdenv) isLinux;
-
-        rust =
-          if builtins.pathExists ./rust-toolchain.toml then
-            rust-bin.fromRustupToolchainFile ./rust-toolchain.toml
-          else if builtins.pathExists ./rust-toolchain then
-            rust-bin.fromRustupToolchainFile ./rust-toolchain
-          else
-            rust-bin.stable.latest.default;
-
-        deps = with pkgs; [ openssl pkgconfig ];
-        rustTools = with pkgs;
-          [ cargo-audit cargo-deny cargo-cross rust-analyzer ]
-          ++ optionals isLinux (with pkgs; [ cargo-watch ]);
     in
     {
-        packages.default = rust;
+      devShell = pkgs.mkShell {
-
+        nativeBuildInputs = with pkgs; [
-        devShells = {
+          rustToolchain
-          default = mkShell {
+          openssl
-            nativeBuildInputs = [ rust ] ++ deps ++ rustTools;
+          pkg-config
+          cargo-audit
+          cargo-deny
+          cargo-cross
+          rust-analyzer
+        ] ++ pkgs.lib.optionals (pkgs.stdenv.isLinux) (with pkgs; [ cargo-watch ]); # Currently broken on macOS
 
         shellHook = ''
-              ${rust}/bin/cargo --version
+          ${pkgs.rustToolchain}/bin/cargo --version
         '';
       };
-        };
     });
 }

scala/flake.nix

@@ -6,35 +6,37 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
     flake-utils.lib.eachDefaultSystem (system:
+
     let
-        jdk = "jdk17";
+      javaVersion = 17;
 
-        config = {
+      overlays = [
-          packageOverrides = p: {
+        (self: super: rec {
-            sbt = p.sbt.override { jre = p.${jdk}; };
+          jdk = super."jdk${toString javaVersion}";
-            scala_3 = p.scala_3.override { jre = p.${jdk}; };
+          sbt = super.sbt.override {
+            jre = jdk;
           };
+          scala = super.scala_3.override {
+            jre = jdk;
           };
+        })
+      ];
 
-        pkgs = import nixpkgs { inherit config jdk system; };
+      pkgs = import nixpkgs { inherit overlays system; };
-
-        inherit (pkgs) mkShell;
-
-        scala = pkgs.scala_3;
-
-        buildTools = with pkgs; [ sbt ];
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ scala sbt coursier ];
-            buildInputs = [ scala ] ++ buildTools;
 
         shellHook = ''
-              ${scala}/bin/scala -version
+          ${pkgs.scala}/bin/scala -version
         '';
       };
-        };
     });
 }

zig/flake.nix

@@ -6,23 +6,23 @@
     nixpkgs.url = "github:NixOS/nixpkgs";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs =
+    { self
+    , flake-utils
+    , nixpkgs
+    }:
+
     flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs { inherit system; };
-        zigPkg = pkgs.zig;
-
-        inherit (pkgs) mkShell;
     in
     {
-        devShells = {
+      devShell = pkgs.mkShell {
-          default = mkShell {
+        buildInputs = with pkgs; [ zig ];
-            buildInputs = [ zigPkg ];
 
         shellHook = ''
-              echo "zig `${zigPkg}/bin/zig version`"
+          echo "zig `${pkgs.zig}/bin/zig version`"
         '';
       };
-        };
     });
 }