diff --git a/lib/build.js b/lib/build.js
index 0ed369e..cd3ed5e 100644
--- a/lib/build.js
+++ b/lib/build.js
@@ -13,21 +13,37 @@ var ntr = require('ntr')
   , modified = require('./modified')
   , dirscanproject = require('./projectscan');
 
+// convert filename to object
 function toO(file){return toExt(file,'.o');}
 
 module.exports = LeoBuild;
 
+// The constructor sets the build environment:
+//   - includes from Arduino project
+//   - libs
+//   - original env
 function LeoBuild(env){
+  if (!env) {
+    env = {};
+  }
+
   if(!this instanceof LeoBuild)
     return new LeoBuild();
 
   this.includes = [].concat(env.includes);
   this.libs = [];
   this.env = env;
+
+  // to enable verbose output
+  this.verbose = env.verbose ? true : false;
 }
 
 LeoBuild.prototype.makeBuildDir = function(){
-  fs.mkdirSync(this.env.build.path);
+  var path = this.env.build.path;
+  if (this.vebose) {
+    console.log('... create build path: ' + path);
+  }
+  fs.mkdirSync(path);
 };
 
 LeoBuild.prototype.clean = function(){
diff --git a/test/build.js b/test/build.js
new file mode 100644
index 0000000..904d2db
--- /dev/null
+++ b/test/build.js
@@ -0,0 +1,23 @@
+var test = require('tape');
+var LeoBuild = require('../lib/build');
+
+test("init leoBuild",function(t){
+  var leoBuild = new LeoBuild();
+
+  t.ok(leoBuild.includes, [], 'no default includes');
+  t.ok(leoBuild.libs, [], 'no default libs');
+  t.ok(leoBuild.env, [], 'no default env');
+  t.notOk(leoBuild.verbose, true, 'no verbose output');
+
+  t.end();
+
+});
+
+test("init leoBuild with verbose output",function(t){
+  var leoBuild = new LeoBuild({verbose: true});
+
+  t.ok(leoBuild.verbose, true, 'enables verbose output');
+
+  t.end();
+
+});