convert to flake

flake.lock

@@ -0,0 +1,42 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1676283394,
+        "narHash": "sha256-XX2f9c3iySLCw54rJ/CZs+ZK6IQy7GXNY4nSOyu2QG4=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "3db36a8b464d0c4532ba1c7dda728f4576d6d073",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1677608380,
+        "narHash": "sha256-k82O23qBAK+43X0KSBjsMYXG2x4kWWXeAmpPTc2KRGY=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "4aba90e89f6d4ac6138939961f62842bd94ec929",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,28 @@
+{
+  description = "nix library extension, containing sophisticated script and code generator functions";
+
+  inputs = {
+    flake-utils.url = "github:numtide/flake-utils";
+    nixpkgs.url = "github:NixOS/nixpkgs";
+  };
+
+  outputs = inputs @ {
+    self,
+    nixpkgs,
+    flake-utils,
+  }: let
+    nix-writersOverlay = import ./pkgs;
+  in
+    {
+      overlays = {
+        nix-writers = nix-writersOverlay;
+        default = nix-writersOverlay;
+      };
+    }
+    // flake-utils.lib.eachDefaultSystem (system: let
+      pkgs = import nixpkgs {inherit system;};
+      nix-writers = nix-writersOverlay pkgs pkgs;
+    in {
+      legacyPackages = nix-writers;
+    });
+}

lib/default.nix

@@ -1,3 +1,4 @@
+{ nixpkgs }:
 let {
   body = lib;
 
@@ -19,6 +20,4 @@ let {
     testString = re: x: match re x != null;
     types = nixpkgs.lib.types // import ./types.nix { lib = body; };
   });
-
-  nixpkgs.lib = import <nixpkgs/lib>;
 }

pkgs/default.nix

@@ -17,9 +17,9 @@
 # nix-build hello_world.nix.
 #
 
-with import ../lib;
+pkgs: oldpkgs:
-
+with import ../lib { nixpkgs = pkgs; };
-pkgs: oldpkgs: {
+{
   exec = name: { filename, argv ? null, envp ? null, destination ? "" }:
     pkgs.writeC name { inherit destination; } /* c */ ''
       #include <unistd.h>