Add nix flake files

flake.lock

@@ -0,0 +1,26 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1731799881,
+        "narHash": "sha256-GRlDXqmwJoW3F0Ymn0ETLsxujLD5idvdaDEzIjF5EEs=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "cd43d6867192ddfb98ba106065a89790e2722b3f",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,53 @@
+{
+  description = "Nix notes.sh dev environment";
+
+  # Flake inputs
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs";
+  };
+
+  # Flake outputs
+  outputs = { self, nixpkgs }:
+    let
+      # Systems supported
+      allSystems = [
+        "x86_64-linux" # 64-bit Intel/AMD Linux
+        "aarch64-linux" # 64-bit ARM Linux
+        "x86_64-darwin" # 64-bit Intel macOS
+        "aarch64-darwin" # 64-bit ARM macOS
+      ];
+
+      # Helper to provide system-specific attributes
+      forAllSystems = f: nixpkgs.lib.genAttrs allSystems (system: f {
+        pkgs = import nixpkgs { inherit system; };
+      });
+
+      make_package = pkgs: pkgs.stdenv.mkDerivation {
+        name = "notes-sh";
+        src = self;
+        nativeBuildInputs = [pkgs.makeWrapper];
+        installPhase = ''
+                mkdir -p $out/bin
+                cp notes.sh $out/bin
+              '';
+
+        postFixup = ''
+          wrapProgram $out/bin/notes.sh \
+            --prefix PATH : ${pkgs.lib.makeBinPath (with pkgs; [ gawk findutils gnused coreutils])}
+        '';
+      };
+    in
+      {
+        devShells = forAllSystems ({ pkgs }: {
+          default = pkgs.mkShell {
+            packages = with pkgs; [
+              fzf
+            ];
+          };
+        });
+        packages = forAllSystems({ pkgs }: rec {notes-sh = make_package pkgs; default=notes-sh;});
+        overlays.default = final: prev: {
+          notes-sh = make_package prev;
+        };
+      };
+}