Add flake.nix to root

default.nix

@@ -1,15 +1,10 @@
-let
+{ pkgs ? import <nixpkgs> { } }:
-  pkgs = import <nixpkgs> {
-    overlays = [
-      (self: super: {
-        buildGoApplication = super.callPackage ./builder { };
-      })
-    ];
-  };
 
+let
+  buildGoApplication = pkgs.buildGoApplication or pkgs.callPackage ./builder { };
   inherit (pkgs) lib;
 
-in pkgs.buildGoApplication {
+in buildGoApplication {
   pname = "gomod2nix";
   version = "0.1";
   src = lib.cleanSource ./.;

flake.lock

@@ -0,0 +1,43 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1603758576,
+        "narHash": "sha256-xKFmWVx+rFInBao3gtmvXcd0LjHD1+0c1Ef5PJDrbuM=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "1dc37370c489b610f8b91d7fdd40633163ffbafd",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs",
+        "utils": "utils"
+      }
+    },
+    "utils": {
+      "locked": {
+        "lastModified": 1601282935,
+        "narHash": "sha256-WQAFV6sGGQxrRs3a+/Yj9xUYvhTpukQJIcMbIi7LCJ4=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "588973065fce51f4763287f0fda87a174d78bf48",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}

flake.nix

@@ -0,0 +1,19 @@
+{
+  description = "Convert go.mod/go.sum to Nix packages";
+
+  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+
+  inputs.utils.url = "github:numtide/flake-utils";
+
+  outputs = { self, nixpkgs, utils }: utils.lib.eachDefaultSystem (system: let
+    pkgs = import nixpkgs { inherit system; };
+  in {
+    overlay = final: prev: {
+      buildGoApplication = final.callPackage ./builder { };
+    };
+
+    defaultPackage = pkgs.callPackage ./default.nix { };
+
+  });
+
+}

overlay.nix

@@ -0,0 +1,3 @@
+self: super: {
+  buildGoApplication = self.callPackage ./builder { };
+}