Build pdf-simple-sign from C++ by default

pdf-simple-sign-master.nix

@@ -1,59 +1,82 @@
 { pkgs ? import <nixpkgs> { }
 , local ? false
 , full ? true
+, go ? false
 }:
-pkgs.buildGoModule rec {
-	pname = "pdf-simple-sign";
-	version = "master";
+let
+	common = rec {
+		pname = "pdf-simple-sign";
+		version = "master";
 
-	# The author recognizes that this is awful.
-	# gropdf-enabled groff build was broken as of writing.
-	nativeCheckInputs = with pkgs; [
-		ncurses
-		inkscape
-		#(groff.override { enableGhostscript = true; })
-		libreoffice
-		imagemagick
+		# The author recognizes that this is awful.
+		# gropdf-enabled groff build was broken as of writing.
+		nativeCheckInputs = with pkgs; [
+			ncurses
+			inkscape
+			#(groff.override { enableGhostscript = true; })
+			libreoffice
+			imagemagick
 
-		openssl
-		# certutil
-		nss.tools
-		# pdfsig
-		(poppler.override { utils = true; })
-	];
+			openssl
+			# certutil
+			nss.tools
+			# pdfsig
+			(poppler.override { utils = true; })
+		];
 
-	src = if local then
-		builtins.path {
-			path = ../${pname}/git;
-			name = "${pname}";
-		}
-	else
-		fetchGit {
-			url = "https://git.janouch.name/p/${pname}.git";
-			submodules = true;
-			ref = "master";
+		src = if local then
+			builtins.path {
+				path = ../${pname}/git;
+				name = "${pname}";
+			}
+		else
+			fetchGit {
+				url = "https://git.janouch.name/p/${pname}.git";
+				submodules = true;
+				ref = "master";
+			};
+
+		doCheck = true;
+
+		# libreoffice doesn't contain the lowriter script.
+		patchPhase = ''
+			sed -i 's/^lowriter/soffice --writer/' test.sh
+		'';
+
+		meta = with pkgs.lib; {
+			description = "Simple PDF signer";
+			homepage = "https://git.janouch.name/p/${pname}";
+			platforms = platforms.all;
+			license = licenses.bsd0;
 		};
-
-#	vendorHash = pkgs.lib.fakeHash;
-	vendorHash = "sha256-05h2f22TPRwadHZfueO8lXKS3Js7d8QVSOrEkY7qUZ8=";
-
-	doCheck = true;
-
-	# libreoffice doesn't contain the lowriter script.
-	patchPhase = ''
-		sed -i 's/^lowriter/soffice --writer/' test.sh
-	'';
-
-	checkPhase = ''
-		runHook preCheck
-		./test.sh $GOPATH/bin/pdf-simple-sign
-		runHook postCheck
-	'';
-
-	meta = with pkgs.lib; {
-		description = "Simple PDF signer";
-		homepage = "https://git.janouch.name/p/${pname}";
-		platforms = platforms.all;
-		license = licenses.bsd0;
 	};
-}
+in if go then
+	pkgs.buildGoModule (common // {
+#		vendorHash = pkgs.lib.fakeHash;
+		vendorHash = "sha256-05h2f22TPRwadHZfueO8lXKS3Js7d8QVSOrEkY7qUZ8=";
+
+		checkPhase = ''
+			runHook preCheck
+			./test.sh $GOPATH/bin/pdf-simple-sign
+			runHook postCheck
+		'';
+	})
+else
+	pkgs.stdenv.mkDerivation (common // {
+		nativeBuildInputs = with pkgs; [
+			meson
+			pkg-config
+			ninja
+			asciidoctor
+		];
+
+		buildInputs = with pkgs; [
+			openssl
+		];
+
+		checkPhase = ''
+			runHook preCheck
+			../test.sh ./pdf-simple-sign
+			runHook postCheck
+		'';
+	})