diff --git a/src/dlangide/builders/builder.d b/src/dlangide/builders/builder.d
index a27cc33..470c891 100644
--- a/src/dlangide/builders/builder.d
+++ b/src/dlangide/builders/builder.d
@@ -1,11 +1,60 @@
 module dlangide.builders.builder;
 
 import dlangide.workspace.project;
+import dlangide.ui.outputpanel;
+import dlangide.builders.extprocess;
+import dlangui.widgets.appframe;
+import std.algorithm;
+import std.string;
+import std.conv;
 
-class Builder {
+class Builder : BackgroundOperationWatcher, ProcessOutputTarget {
     protected Project _project;
+    protected ExternalProcess _extprocess;
+    protected OutputPanel _log;
 
     @property Project project() { return _project; }
     @property void project(Project p) { _project = p; }
 
+    this(AppFrame frame, Project project, OutputPanel log) {
+        super(frame);
+        _project = project;
+        _log = log;
+        _extprocess = new ExternalProcess();
+    }
+    /// log lines
+    override void onText(dstring text) {
+        dstring[] lines = text.split('\n');
+        _log.addLogLines(null, lines);
+    }
+
+    /// returns icon of background operation to show in status line
+    override @property string icon() { return "folder"; }
+    /// update background operation status
+    override void update() {
+        if (_extprocess.state == ExternalProcessState.None) {
+            onText("Running dub\n"d);
+            _extprocess.run(cast(char[])"dub", cast(char[][])["build"], cast(char[])_project.dir, this, null);
+            if (_extprocess.state != ExternalProcessState.Running) {
+                onText("Failed to run builder tool");
+                _finished = true;
+                destroy(_extprocess);
+                _extprocess = null;
+                return;
+            }
+        }
+        ExternalProcessState state = _extprocess.poll();
+        if (state == ExternalProcessState.Stopped) {
+            onText("Builder finished with result "d ~ to!dstring(_extprocess.result) ~ "\n"d);
+            _finished = true;
+            return;
+        }
+        if (_cancelRequested) {
+            _extprocess.kill();
+            _extprocess.wait();
+            _finished = true;
+            return;
+        }
+        super.update();
+    }
 }
diff --git a/src/dlangide/builders/extprocess.d b/src/dlangide/builders/extprocess.d
index 4828cc9..adbd616 100644
--- a/src/dlangide/builders/extprocess.d
+++ b/src/dlangide/builders/extprocess.d
@@ -235,8 +235,9 @@ class ExternalProcess {
     ExternalProcessState kill() {
         if (_state == ExternalProcessState.Error || _state == ExternalProcessState.None || _state == ExternalProcessState.Stopped)
             return _state;
-        if (_state == ExternalProcessState.Stopping) {
+        if (_state == ExternalProcessState.Running) {
             std.process.kill(_pipes.pid);
+            _state = ExternalProcessState.Stopping;
         }
         return _state;
     }
diff --git a/src/dlangide/ui/frame.d b/src/dlangide/ui/frame.d
index a0fa313..7bc17cd 100644
--- a/src/dlangide/ui/frame.d
+++ b/src/dlangide/ui/frame.d
@@ -21,6 +21,7 @@ import dlangide.ui.dsourceedit;
 import dlangide.ui.homescreen;
 import dlangide.workspace.workspace;
 import dlangide.workspace.project;
+import dlangide.builders.builder;
 
 import std.conv;
 import std.utf;
@@ -146,6 +147,7 @@ class IDEFrame : AppFrame {
             TabItem tab = _tabs.tab(index);
             ProjectSourceFile file = cast(ProjectSourceFile)tab.objectParam;
             if (file) {
+                setCurrentProject(file.project);
                 // tab is source file editor
                 _wsPanel.selectItem(file);
                 focusEditor(file.filename);
@@ -378,7 +380,8 @@ class IDEFrame : AppFrame {
                     return true;
                 case IDEActions.BuildProject:
                 case IDEActions.BuildWorkspace:
-                    setBackgroundOperation(new BackgroundOperationWatcherTest(this));
+                    buildProject();
+                    //setBackgroundOperation(new BackgroundOperationWatcherTest(this));
                     return true;
                 case IDEActions.WindowCloseAllDocuments:
                     askForUnsavedEdits(delegate() {
@@ -470,6 +473,18 @@ class IDEFrame : AppFrame {
         currentWorkspace = ws;
         _wsPanel.workspace = ws;
     }
+
+    Project currentProject;
+    void setCurrentProject(Project project) {
+        currentProject = project;
+    }
+
+    void buildProject() {
+        if (!currentProject)
+            return;
+        Builder op = new Builder(this, currentProject, _logPanel);
+        setBackgroundOperation(op);
+    }
 }
 
 Widget createAboutWidget() 
diff --git a/src/dlangide/workspace/project.d b/src/dlangide/workspace/project.d
index c5c3ab8..1d7abd1 100644
--- a/src/dlangide/workspace/project.d
+++ b/src/dlangide/workspace/project.d
@@ -157,6 +157,11 @@ class WorkspaceItem {
         return _filename;
     }
 
+    /// workspace item directory
+    @property string dir() {
+        return _dir;
+    }
+
     /// file name of workspace item
     @property void filename(string fname) {
         if (fname.length > 0) {