diff --git a/processing/app/KjcEngine.java b/processing/app/KjcEngine.java
index 8cca28c56..60c7ab055 100644
--- a/processing/app/KjcEngine.java
+++ b/processing/app/KjcEngine.java
@@ -16,7 +16,7 @@ import com.oroinc.text.regex.*;
 // doesn't really need to extend kjc.Main anymore, 
 // since reportTrouble doesn't actually do any good
 
-public class KjcEngine implements PdeEngine {
+public class KjcEngine extends PdeEngine {
   static String TEMP_CLASS = "Temporary";
   static final String EXTENDS = "extends BApplet ";
   static final String EXTENDS_KJC = "extends KjcApplet ";
@@ -39,7 +39,7 @@ public class KjcEngine implements PdeEngine {
   KjcMessageStream messageStream;
 
   String program;
-  PdeEditor editor;
+  //PdeEditor editor;
   String buildPath;
 
   boolean running;
@@ -52,12 +52,15 @@ public class KjcEngine implements PdeEngine {
   boolean usingExternal;
 
 
-  public KjcEngine(String program, String buildPath, 
-		   String dataPath, PdeEditor editor) {
+  public KjcEngine(PdeEditor editor, 
+		   String program, String buildPath, 
+		   String dataPath) {
+    super(editor);
+
     this.program = program;
     this.buildPath = buildPath;
     //this.buildPath = "lib" + File.separator + "build";
-    this.editor = editor;
+    //this.editor = editor;
     
     // only run cleanup if using the applications temp dir
     //if (buildPath.endsWith("build")) cleanup();
@@ -561,7 +564,7 @@ public class KjcEngine implements PdeEngine {
   }
 
 
-  public void start() throws PdeException {
+  public void start() throws PdeException {  // part of PdeEngine
     int numero1 = (int) (Math.random() * 10000);
     int numero2 = (int) (Math.random() * 10000);
     tempClass = TEMP_CLASS + "_" + numero1 + "_" + numero2;
@@ -820,7 +823,12 @@ public class KjcEngine implements PdeEngine {
   }
 
 
-  public void cleanup() {
+  public void front() {  // part of PdeEngine
+    window.toFront();
+  }
+
+
+  protected void cleanup() {
     File buildDir = new File(buildPath);
     if (!buildDir.exists()) buildDir.mkdirs();
 
@@ -854,7 +862,8 @@ public class KjcEngine implements PdeEngine {
   }
 
 
-  public void stop() {
+  public void stop() {  // part of PdeEngine
+    //System.out.println("PdeEngine.stop");
     running = false;
 
     //System.out.println();
@@ -901,7 +910,7 @@ public class KjcEngine implements PdeEngine {
   }
 
 
-  public void close() {
+  public void close() {  // part of PdeEngine
     //if (window != null) window.hide();
     if (window != null) {
       //System.err.println("disposing window");
@@ -911,9 +920,9 @@ public class KjcEngine implements PdeEngine {
   }
 
 
-  public void inform(String message) { 
-    System.out.println("informing: " + message);
-  }
+  //public void inform(String message) { 
+  //System.out.println("informing: " + message);
+  //}
 }
 
 
diff --git a/processing/app/PdeBase.java b/processing/app/PdeBase.java
index 3b3fe701f..a3de374a7 100644
--- a/processing/app/PdeBase.java
+++ b/processing/app/PdeBase.java
@@ -400,11 +400,13 @@ public class PdeBase implements ActionListener {
 
 
   // does this do anything useful?
+  /*
   public void destroy() {
     if (editor != null) {
       editor.terminate();
     }
   }
+  */
 
   /*
   public void paint(Graphics g) {
diff --git a/processing/app/PdeEditor.java b/processing/app/PdeEditor.java
index 8d47d706c..64ae69707 100644
--- a/processing/app/PdeEditor.java
+++ b/processing/app/PdeEditor.java
@@ -42,7 +42,8 @@ public class PdeEditor extends Panel {
   //String lastDirectory;
   //String lastFile;
 
-  PdeRunner runner;
+  //PdeRunner runner;
+  KjcEngine engine;
 
   Frame frame;
   Window presentationWindow;
@@ -112,7 +113,7 @@ public class PdeEditor extends Panel {
     //textarea.addKeyListener(new PdeKeyListener(this));
     //}
 
-    runner = new PdeRunner(this);
+    //runner = new PdeRunner(this);
   }
 
 
@@ -180,11 +181,43 @@ public class PdeEditor extends Panel {
     running = true;
     buttons.run();
 
-    runner.setProgram(textarea.getText());
-    runner.start();
+    //runner.setProgram(textarea.getText());
+    //runner.start();
 
+    try {
+      String program = textarea.getText();
+      if (program.length() != 0) {
+	String buildPath = "lib" + File.separator + "build";  // TEMPORARY
+	File buildDir = new File(buildPath);
+	if (!buildDir.exists()) buildDir.mkdirs();
+
+	String dataPath = 
+	  sketchFile.getParent() + File.separator + "data";
+	  //editor.sketchFile.getParent() + File.separator + "data";
+
+	engine = new KjcEngine(this, program, buildPath, dataPath);
+	engine.start();
+	//System.out.println("done iwth engine.start()");
+      }
+
+    } catch (PdeException e) { 
+      //state = RUNNER_ERROR;
+      //forceStop = false;
+      //this.stop();
+      engine.stop();
+      e.printStackTrace();
+      //editor.error(e);
+      error(e);
+
+    } catch (Exception e) {
+      e.printStackTrace();
+      //this.stop();
+      engine.stop();
+    }	
+    //engine = null;
+    //System.out.println("out of doRun()");
     // required so that key events go to the panel and <key> works
-    //graphics.requestFocus();  // removed for pde
+    //graphics.requestFocus();  // removed for pde    
   }
 
 
@@ -261,7 +294,8 @@ public class PdeEditor extends Panel {
 	    //presentationWindow.toBack();
 	    if (frame != null) frame.toFront();
 	    try {
-	      ((KjcEngine)(runner.engine)).window.toFront();
+	      //((KjcEngine)(runner.engine)).window.toFront();
+	      engine.front();
 	    } catch (Exception ex) { }
 	  }
 	}
@@ -283,7 +317,9 @@ public class PdeEditor extends Panel {
     */
 
     try {
-      ((KjcEngine)(runner.engine)).window.toFront();
+      //((KjcEngine)(runner.engine)).window.toFront();
+      engine.front();
+
     } catch (Exception e) {
       // rather than writing code to check all the posible
       // errors with the above statement, just fail quietly
@@ -320,7 +356,14 @@ public class PdeEditor extends Panel {
     //#ifdef RECORDER
     //    if (!running) return;
     //#endif
-    terminate();
+
+    //terminate(); 
+    // following 3 replace terminate
+    //runner.stop();
+    //System.out.println("doStop, engine is " + engine);
+    if (engine != null) engine.stop();
+    message(EMPTY);
+
     buttons.clear();
     running = false;
 
@@ -343,11 +386,17 @@ public class PdeEditor extends Panel {
     // some code to close the window here
     try {
       // runner.engine is null (runner is not)
-      ((KjcEngine)(runner.engine)).close();
+      //((KjcEngine)(runner.engine)).close();
+      engine.close();
+
       // runner shouldn't be set to null because it gets reused
       //System.err.println("runner = " + runner);
       //runner = null;
+      // engine not reused
+      engine = null; // will this help?
+
     } catch (Exception e) { }
+
     buttons.clear();
   }
 
@@ -804,16 +853,16 @@ public class PdeEditor extends Panel {
       // create the project directory
       // pass null for datapath because the files shouldn't be 
       // copied to the build dir.. that's only for the temp stuff
-      KjcEngine engine = new KjcEngine(program, appletDir.getPath(), 
-				       null, this);
+      KjcEngine ex_engine = new KjcEngine(this, program, 
+					  appletDir.getPath(), null);
 				       //dataDir.getPath(), this);
       //File projectDir = new File(appletDir, projectName);
       //projectDir.mkdirs();
       appletDir.mkdirs();
 
       // projectName will be updated with actual class name
-      exportSketchName = engine.writeJava(exportSketchName, false);
-      if (!engine.compileJava()) {
+      exportSketchName = ex_engine.writeJava(exportSketchName, false);
+      if (!ex_engine.compileJava()) {
 	//throw new Exception("error while compiling, couldn't export");
 	// message() will already have error message in this case
 	return;
@@ -827,7 +876,7 @@ public class PdeEditor extends Panel {
       //copyFile(new File(javaName), new File(appletDir, javaName));
 
       // remove temporary .java and .class files
-      //engine.cleanup();
+      //ex_engine.cleanup();
 
       int wide = BApplet.DEFAULT_WIDTH;
       int high = BApplet.DEFAULT_HEIGHT;
@@ -933,7 +982,7 @@ public class PdeEditor extends Panel {
       zos.close();
       //zipOutputFile.close();
 
-      //engine.cleanup();  // no! buildPath is applet!
+      //ex_engine.cleanup();  // no! buildPath is applet!
 
       message("Done exporting.");
 
@@ -1125,10 +1174,13 @@ public class PdeEditor extends Panel {
   }
 
 
+  /*
   public void terminate() {   // part of PdeEnvironment
-    runner.stop();
+    //runner.stop();
+    if (engine != null) engine.stop();
     message(EMPTY);
   }
+  */
 
 
   // TODO iron out bugs with this code under
diff --git a/processing/app/PdeEngine.java b/processing/app/PdeEngine.java
index 8a052e520..e48347a58 100644
--- a/processing/app/PdeEngine.java
+++ b/processing/app/PdeEngine.java
@@ -1,5 +1,21 @@
-public interface PdeEngine {
-  public void start() throws PdeException;
-  public void stop();
-  public void close();
+public class PdeEngine {
+  PdeEditor editor;
+
+  public PdeEngine(PdeEditor editor) {
+    this.editor = editor;
+  }
+
+  // implemented by subclasses
+
+  public void start() throws PdeException {
+  }
+
+  public void front() {
+  }
+
+  public void stop() {
+  }
+
+  public void close() {
+  }
 }
diff --git a/processing/app/PdeRunner.java b/processing/app/PdeRunner.java
deleted file mode 100644
index 6f726ee69..000000000
--- a/processing/app/PdeRunner.java
+++ /dev/null
@@ -1,189 +0,0 @@
-import java.io.*;
-//import java.util.*;
-
-
-public class PdeRunner /*implements Runnable*/ {
-  //DbnGraphics graphics;
-  //PdeEnvironment env;
-  PdeEditor editor;
-  String program;
-
-  PdeEngine engine;
-  // dbn definitely needs an engine, 
-  // for the others it's just an interface
-
-  static final int RUNNER_STARTED = 0;
-  static final int RUNNER_FINISHED = 1;
-  static final int RUNNER_ERROR = -1;
-  static final int RUNNER_STOPPED = 2;
-  int state = RUNNER_FINISHED;
-
-  Thread thread;
-  boolean forceStop;
-
-
-  public PdeRunner(PdeEditor editor) {
-    this(editor, "");
-  }
-
-  public PdeRunner(PdeEditor editor, String program) { 
-    this.program = program;
-    this.editor = editor;
-  }
-
-
-  public void setProgram(String program) {
-    this.program = program;
-  }
-
-
-  public void start() {
-    run(); 
-    /*
-    if (thread != null) {
-      try { 
-	thread.stop(); 
-      } catch (Exception e) { }
-      thread = null;
-    }
-    thread = new Thread(this, "PdeRunner");
-    thread.start();
-    */
-  }
-
-
-  public void run() {
-    state = RUNNER_STARTED;
-    //graphics.reset();  // remove for pde
-    //System.out.println("running");
-
-    try {
-      if (program.length() == 0) {
-	// hotspot vm or jikes 1.16 requires something
-	// to be here.. bad code getting compiled somewhere
-	System.out.println("no program");
-
-	/*
-      } else if (program.indexOf('#') < 2) { //charAt(0) == '#') {
-#ifdef PYTHON
-
-#ifdef OPENGL
-	program = "#\r\n" + 
-	  "import DbnEditorGraphics3D\r\n" +
-	  "import ExperimentalCanvas\r\n" +
-	  "g = DbnEditorGraphics3D.getCurrentGraphics()\r\n" +
-	  "glc = g.canvas\r\n" +
-	  "gl = glc.getGL()\r\n" +
-	  "glj = glc.getGLJ()\r\n" + program;
-#endif
-
-	forceStop = true;
-	engine = new PythonEngine(program);
-	engine.start();
-	forceStop = false;
-#else
-	throw new Exception("python support not included");
-#endif
-	*/
-
-	//      } else if (program.indexOf("extends ProcessingApplet") != -1) {
-	//#ifdef JAVAC
-	//	engine = new JavacEngine(program, graphics);
-	//	engine.start();
-	//#else
-	//	throw new Exception("javac support not included");
-	//#endif
-
-      } else {
-	/*
-	forceStop = true;
-	engine = new PythonEngine(program);
-	engine.start();
-	forceStop = false;
-	*/
-	//System.out.println("over here");
-
-	//engine = new KjcEngine(program, "lib", editor);
-	//this.buildPath = "lib" + File.separator + "build";  // TEMPORARY
-	//String buildPath = 
-	//editor.sketchFile.getParent() + File.separator + "build";
-	String buildPath = "lib" + File.separator + "build";  // TEMPORARY
-	File buildDir = new File(buildPath);
-	if (!buildDir.exists()) buildDir.mkdirs();
-
-	String dataPath = 
-	  editor.sketchFile.getParent() + File.separator + "data";
-
-	/*
-	Properties props = System.getProperties();
-	String cp = props.getProperty("java.class.path");
-	System.out.println("in: " + cp);
-	props.put("java.class.path", 
-		  cp + File.pathSeparator + buildPath);
-	String cp2 = props.getProperty("java.class.path");
-	System.out.println("out: " + cp2);
-	System.setProperties(props);
-	*/
-	//System.out.println("over here2");
-
-	engine = new KjcEngine(program, buildPath, dataPath, editor);
-	//System.out.println("over here3");
-
-	engine.start();
-
-	/*
-	while (!((KjcEngine)engine).applet.finished) { 
-	  System.out.println("waiting");
-	  try {
-	    Thread.sleep(500);
-	  } catch (InterruptedException e) { }
-	}
-	*/
-      }
-
-      // maybe this code shouldn't be called automatically, 
-      // and instead ProcessingApplet and the others 
-      // must call it explicitly
-      //System.out.println("finished");
-      /*
-      state = RUNNER_FINISHED;
-      System.out.println("finishing");
-      env.finished();
-      */
-      //graphics.update();  // removed for pde
-
-    } catch (PdeException e) { 
-      state = RUNNER_ERROR;
-      forceStop = false;
-      this.stop();
-      e.printStackTrace();
-      editor.error(e);
-
-    } catch (Exception e) {
-      e.printStackTrace();
-      this.stop();
-    }	
-  }
-
-
-  public void finished() {  // called by KjcProcessingApplet or something
-    state = RUNNER_FINISHED;
-    editor.finished();
-  }
-
-
-  public void stop() {
-    if (engine != null) {
-      engine.stop();
-      ((KjcEngine)engine).cleanup();
-      /*
-      if (forceStop) {
-	thread.stop();
-	thread = null;
-      }
-      */
-      // is this necessary [fry]
-      //engine = null;
-    }
-  }
-}
diff --git a/processing/todo.txt b/processing/todo.txt
index 80ff25d0d..b9532cfdb 100644
--- a/processing/todo.txt
+++ b/processing/todo.txt
@@ -23,12 +23,11 @@ o background() not working
 X   checked but couldn't duplicate
 X change editorlistener properties to use underscores
 X imageMode() was gone.. now replaced
-
-_ collapse pdeengine/pderunner/kjcengine
-_   remove 'extends' from kjcengine, make an instance of Main
-_     may need to subclass at.dms.kjc.Main to override the exit()
-_   make pdeengine a class
-_   remove pderunner, collapse into pdeengine
+X collapse pdeengine/pderunner/kjcengine
+X   remove 'extends' from kjcengine, make an instance of Main
+X     may need to subclass at.dms.kjc.Main to override the exit()
+X   make pdeengine a class
+X   remove pderunner, collapse into pdeengine
 
 _ save window position (only during session) of sketch run window
 _ present mode should hide editor frame