Add flake and devshell

flake.lock

@@ -0,0 +1,88 @@
+{
+  "nodes": {
+    "devshell": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "systems": [
+          "systems"
+        ]
+      },
+      "locked": {
+        "lastModified": 1695973661,
+        "narHash": "sha256-BP2H4c42GThPIhERtTpV1yCtwQHYHEKdRu7pjrmQAwo=",
+        "owner": "numtide",
+        "repo": "devshell",
+        "rev": "cd4e2fda3150dd2f689caeac07b7f47df5197c31",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "devshell",
+        "type": "github"
+      }
+    },
+    "flake-utils": {
+      "inputs": {
+        "systems": [
+          "systems"
+        ]
+      },
+      "locked": {
+        "lastModified": 1694529238,
+        "narHash": "sha256-zsNZZGTGnMOf9YpHKJqMSsa0dXbfmxeoJ7xHlrt+xmY=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "ff7b65b44d01cf9ba6a71320833626af21126384",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1696697597,
+        "narHash": "sha256-q26Qv4DQ+h6IeozF2o1secyQG0jt2VUT3V0K58jr3pg=",
+        "owner": "nixos",
+        "repo": "nixpkgs",
+        "rev": "5a237aecb57296f67276ac9ab296a41c23981f56",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nixos",
+        "ref": "nixos-23.05",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "devshell": "devshell",
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs",
+        "systems": "systems"
+      }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,38 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at https://mozilla.org/MPL/2.0/.
+# SPDX-License-Identifier: MPL-2.0
+{
+  inputs = {
+    devshell = {
+      url = "github:numtide/devshell";
+      inputs.nixpkgs.follows = "nixpkgs";
+      inputs.systems.follows = "systems";
+    };
+    flake-utils = {
+      url = "github:numtide/flake-utils";
+      inputs.systems.follows = "systems";
+    };
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-23.05";
+    systems.url = "github:nix-systems/default";
+  };
+  outputs = {
+    devshell,
+    flake-utils,
+    nixpkgs,
+    ...
+  }: (flake-utils.lib.eachDefaultSystem (system: let
+    pkgs = import nixpkgs {
+      inherit system;
+      overlays = [devshell.overlays.default];
+    };
+  in {
+    formatter = pkgs.alejandra;
+    devShells.default = pkgs.devshell.mkShell {
+      commands = [
+        {package = pkgs.exercism;}
+        {package = pkgs.nil;}
+      ];
+    };
+  }));
+}