diff --git a/.envrc b/.envrc
new file mode 100644
index 0000000..3550a30
--- /dev/null
+++ b/.envrc
@@ -0,0 +1 @@
+use flake
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 0000000..0379900
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,114 @@
+{
+  "nodes": {
+    "devshell": {
+      "inputs": {
+        "nixpkgs": "nixpkgs",
+        "systems": "systems"
+      },
+      "locked": {
+        "lastModified": 1701787589,
+        "narHash": "sha256-ce+oQR4Zq9VOsLoh9bZT8Ip9PaMLcjjBUHVPzW5d7Cw=",
+        "owner": "numtide",
+        "repo": "devshell",
+        "rev": "44ddedcbcfc2d52a76b64fb6122f209881bd3e1e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "devshell",
+        "type": "github"
+      }
+    },
+    "flake-parts": {
+      "inputs": {
+        "nixpkgs-lib": "nixpkgs-lib"
+      },
+      "locked": {
+        "lastModified": 1701473968,
+        "narHash": "sha256-YcVE5emp1qQ8ieHUnxt1wCZCC3ZfAS+SRRWZ2TMda7E=",
+        "owner": "hercules-ci",
+        "repo": "flake-parts",
+        "rev": "34fed993f1674c8d06d58b37ce1e0fe5eebcb9f5",
+        "type": "github"
+      },
+      "original": {
+        "id": "flake-parts",
+        "type": "indirect"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1677383253,
+        "narHash": "sha256-UfpzWfSxkfXHnb4boXZNaKsAcUrZT9Hw+tao1oZxd08=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "9952d6bc395f5841262b006fbace8dd7e143b634",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs-lib": {
+      "locked": {
+        "dir": "lib",
+        "lastModified": 1701253981,
+        "narHash": "sha256-ztaDIyZ7HrTAfEEUt9AtTDNoCYxUdSd6NrRHaYOIxtk=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "e92039b55bcd58469325ded85d4f58dd5a4eaf58",
+        "type": "github"
+      },
+      "original": {
+        "dir": "lib",
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_2": {
+      "locked": {
+        "lastModified": 1702312524,
+        "narHash": "sha256-gkZJRDBUCpTPBvQk25G0B7vfbpEYM5s5OZqghkjZsnE=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "a9bf124c46ef298113270b1f84a164865987a91c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "devshell": "devshell",
+        "flake-parts": "flake-parts",
+        "nixpkgs": "nixpkgs_2"
+      }
+    },
+    "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
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 0000000..51afcff
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,23 @@
+{
+  description = "Gmail Filter Builder";
+
+  inputs = {
+    devshell.url = "github:numtide/devshell";
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+  };
+
+  outputs = inputs@{ flake-parts, ... }:
+    flake-parts.lib.mkFlake { inherit inputs; } {
+      imports = [ inputs.devshell.flakeModule ];
+
+      systems = [ "x86_64-linux" ];
+
+      perSystem = { config, self', inputs', pkgs, system, ... }: {
+        formatter = pkgs.nixpkgs-fmt;
+
+        devshells.default = {
+          packages = with pkgs; [ "php81" "php81Packages.composer" ];
+        };
+      };
+    };
+}