Create nix derivation with and without flakes

Makefile

@@ -1,8 +1,15 @@
+UNAME_S := $(shell uname -s)
+ifeq ($(UNAME_S),Darwin)
+  SED := $(shell command -v gsed 2>/dev/null)
+else
+  SED := sed
+endif
+
 BINARY_NAME := dnsimple
 VERSION := $(shell git describe --tags --always --dirty 2>/dev/null || echo "dev")
 LDFLAGS := -ldflags "-X main.version=$(VERSION)"
 
-.PHONY: build install test lint clean
+.PHONY: build install test lint clean nix-update-hash
 
 build:
 	go build $(LDFLAGS) -o bin/$(BINARY_NAME) ./cmd/dnsimple
@@ -18,3 +25,14 @@ lint:
 
 clean:
 	rm -rf bin/
+
+nix-update-hash:
+ifndef SED
+	$(error gsed is required on macOS — install with: brew install gnu-sed)
+endif
+	@OLD_HASH=$$(grep 'vendorHash' default.nix | $(SED) 's/.*"\(.*\)".*/\1/') && \
+		$(SED) -i 's|vendorHash = ".*"|vendorHash = lib.fakeHash|' default.nix && \
+		NEW_HASH=$$(nix-build -E 'with import <nixpkgs> {}; callPackage ./default.nix {}' 2>&1 | grep 'got:' | awk '{print $$2}') && \
+		$(SED) -i "s|vendorHash = lib.fakeHash|vendorHash = \"$$NEW_HASH\"|" default.nix && \
+		echo "Updated vendorHash to $$NEW_HASH" || \
+		($(SED) -i "s|vendorHash = lib.fakeHash|vendorHash = \"$$OLD_HASH\"|" default.nix && echo "Failed to compute hash" && exit 1)

default.nix

@@ -0,0 +1,30 @@
+{
+  lib,
+  buildGoModule,
+  version ? "dev",
+}:
+
+buildGoModule {
+  pname = "dnsimple";
+  inherit version;
+
+  src = lib.cleanSource ./.;
+
+  vendorHash = "sha256-4dOKR9BYsmL083eCBpZzXRPr3CHBYF4Kc+HMo6v9MU0=";
+
+  ldflags = [
+    "-s"
+    "-w"
+    "-X main.version=${version}"
+  ];
+
+  subPackages = [ "cmd/dnsimple" ];
+
+  meta = with lib; {
+    description = "Command-line interface for the DNSimple API";
+    homepage = "https://github.com/dnsimple/dnsimple-cli";
+    license = licenses.mit;
+    maintainers = [ "DNSimple" ];
+    mainProgram = "dnsimple";
+  };
+}

flake.nix

@@ -0,0 +1,44 @@
+{
+  description = "Command-line interface for the DNSimple API";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+  };
+
+  outputs =
+    { self, nixpkgs }:
+    let
+      supportedSystems = [
+        "x86_64-linux"
+        "aarch64-linux"
+        "x86_64-darwin"
+        "aarch64-darwin"
+      ];
+      forAllSystems = nixpkgs.lib.genAttrs supportedSystems;
+      version = self.shortRev or self.dirtyShortRev or "dev";
+    in
+    {
+      packages = forAllSystems (
+        system:
+        let
+          pkgs = nixpkgs.legacyPackages.${system};
+        in
+        {
+          dnsimple = pkgs.callPackage ./default.nix { inherit version; };
+          default = self.packages.${system}.dnsimple;
+        }
+      );
+
+      devShells = forAllSystems (
+        system:
+        let
+          pkgs = nixpkgs.legacyPackages.${system};
+        in
+        {
+          default = pkgs.mkShell {
+            buildInputs = [ pkgs.go ];
+          };
+        }
+      );
+    };
+}