diff --git a/source/main.ts b/source/main.ts
index 809e921..850ef04 100644
--- a/source/main.ts
+++ b/source/main.ts
@@ -27,8 +27,10 @@ namespace _munin
 		command : string,
 		{
 			"log_only": log_only = false,
+			"working_directory": working_directory = null,
 		} : {
 			log_only ?: boolean;
+			working_directory ?: (null | string);
 		} = {
 		}
 	) : Promise<
@@ -64,6 +66,7 @@ namespace _munin
 						nm_child_process.exec(
 							command,
 							{
+								"cwd": ((working_directory === null) ? undefined : working_directory),
 							},
 							(error, stdout, stderr) => {
 								if (error) {
@@ -218,35 +221,34 @@ namespace _munin
 					for (const lib of data.libs) {
 						switch (lib.kind) {
 							case "plankton": {
+								const directory : string = lib_plankton.string.coin(
+									"{{directory}}/plankton",
+									{
+										"directory": conf.directories.libs,
+									}
+								);
 								/**
-								 * @todo outsource
+								 * @todo do not use "execute" for that
 								 */
-								const conf = {
-									"directory": "libs/plankton",
-								};
-								const commands : Array<string> = [
+								await execute(
 									lib_plankton.string.coin(
 										"mkdir -p {{directory}}",
 										{
-											"directory": conf.directory,
+											"directory": directory,
 										}
-									),
-									lib_plankton.string.coin(
-										"cd {{directory}}",
-										{
-											"directory": conf.directory,
-										}
-									),
+									)
+								);
+								await execute(
 									lib_plankton.string.coin(
 										"ptk bundle node {{modules}}",
 										{
 											"modules": lib.data.modules.join(" "),
 										}
 									),
-								];
-								for (const command of commands) {
-									await execute(command);
-								}
+									{
+										"working_directory": directory,
+									}
+								);
 								break;
 							}
 							case "node": {
@@ -280,6 +282,9 @@ namespace _munin
 							}
 						),
 					];
+					/**
+					 * @todo do not use "execute" for that
+					 */
 					for (const command of commands) {
 						await execute(command);
 					}