diff --git a/project.clj b/project.clj
index 0f8c5c1..5f96cf8 100644
--- a/project.clj
+++ b/project.clj
@@ -1,4 +1,5 @@
 (defproject hulkure "1.0.0-SNAPSHOT"
   :description "FIXME: write description"
+  :main hulkure.editor
   :dependencies [[org.clojure/clojure "1.4.0"]
                  [org.clojure/data.json "0.2.0"]])
diff --git a/src/hulkure/board.clj b/src/hulkure/board.clj
index 98d4f64..0fcbe44 100644
--- a/src/hulkure/board.clj
+++ b/src/hulkure/board.clj
@@ -1,6 +1,7 @@
 (ns hulkure.board
   (:require [clojure.data.json :as json])
-  (:use [hulkure.utils :only [filter-first]]))
+  (:use [hulkure.utils :only [filter-first
+                              removev]]))
 
 (defn make-board []
   {:fields [], ; contains fields. The keys :x and :y are handled like unique keys
@@ -15,16 +16,30 @@
 
 (defn- get-field-with-index [board x y]
   "returns [index field]"
-  (or (filter-first #(and (= x (% :x))
-                          (= y (% :y)))
+  (or (filter-first #(and (= x ((second %) :x))
+                          (= y ((second %) :y)))
                     (map-indexed vector (board :fields)))
       [nil nil]))
 
 (defn- get-field-index [board x y]
   (first (get-field-with-index board x y)))
 
-(defn get-field [board x y]
-  (last (get-field-with-index board x y)))
+(defn get-field
+  ([board xy]
+     (get-field board (xy :x) (xy :y)))
+  ([board x y]
+     (last (get-field-with-index board x y))))
+
+(defn remove-field
+  "remove field at coordinates x and y. Warning: does not handle figures at specified coordinates."
+  ([board xy]
+     (remove-field board (xy :x) (xy :y)))
+  ([board x y]
+     (let [[index field] (get-field-with-index board x y)]
+       (if index
+         (assoc board :fields (removev (board :fields)
+                                       index))
+         board))))
 
 (defn set-field [board field]
   "Update or add field if it does not exist"
diff --git a/src/hulkure/editor.clj b/src/hulkure/editor.clj
index 05a2f1a..0259a1f 100644
--- a/src/hulkure/editor.clj
+++ b/src/hulkure/editor.clj
@@ -1,27 +1,78 @@
 (ns hulkure.editor
+  (:require [hulkure.board :as board])
   (:import [javax.swing JFrame JPanel JMenuBar JMenu JMenuItem KeyStroke AbstractAction]
            [java.awt Graphics Color]
-           [java.awt.event KeyEvent ActionEvent ActionListener]))
+           [java.awt.event KeyEvent ActionEvent ActionListener MouseAdapter MouseEvent]))
 
-(defn start-editor []
+(defn reset-board! [state]
+  (swap! state assoc :board (board/make-board)))
+
+(defn paint [#^Graphics this state g]
+  (.setColor g Color/BLACK)
+  (.fillRect g 0 0 (.getWidth this) (.getHeight this))
+  (.setColor g Color/GRAY)
+  (dorun (map #(.fillRect g (inc (* 20 (% :x))) (inc (* 20 (% :y))) (- 20 2) (- 20 2))
+              (get-in @state [:board :fields])))
+  (when-let [mouse (@state :mouse-over)]
+    (do
+     (.setColor g Color/RED)
+     (.drawRect g (* 20 (mouse :x)) (* 20 (mouse :y)) 20 20))))
+
+(defn translate-screen-to-board [x y]
+  {:x (int (/ x 20))
+   :y (int (/ y 20))})
+
+(defn make-mouse-adapter [state]
+  (proxy [MouseAdapter] []
+    (mouseMoved [#^MouseEvent event]
+      (swap! state assoc :mouse-over (translate-screen-to-board(.getX event) (.getY event)))
+      (.repaint (@state :panel)))
+    (mouseClicked [#^MouseEvent event]
+      (let [coords (translate-screen-to-board (.getX event) (.getY event))]
+        (swap! state assoc :board (if (board/get-field (@state :board) coords)
+                                    (board/remove-field (@state :board) coords)
+                                    (board/set-field (@state :board) coords)))
+        (.repaint (@state :panel))))))
+
+(defn make-content-pane [state]
+  (proxy [JPanel] []
+    (paintComponent [#^Graphics g]
+      (paint this state g))))
+
+(defn make-action-new [state]
+  (proxy [AbstractAction] ["New"]
+    (actionPerformed [e]
+      (reset-board! state)
+      (.repaint (@state :panel)))))
+
+(defn make-action-exit []
+  (proxy [AbstractAction] ["Exit"]
+    (actionPerformed [e]
+      (System/exit 0))))
+
+(defn start-editor [state]
   (let [frame (JFrame. "Editor")
-        actionListener (proxy [AbstractAction ActionListener] []
-                         (actionPerformed [e]
-                           (prn e)))]
+        mouse-adapter (make-mouse-adapter state)
+        content-pane (make-content-pane state)]
+    (swap! state assoc :panel content-pane)
     (.setDefaultCloseOperation frame JFrame/DISPOSE_ON_CLOSE)
-    (.setContentPane frame (proxy [JPanel] []
-                             (paintComponent [#^Graphics g]
-                               (.setColor g Color/BLACK)
-                               (.fillRect g 0 0 (.getWidth this) (.getHeight this)))))
+    (.setContentPane frame content-pane)
     (.setJMenuBar frame (doto (JMenuBar.)
-                    (.add (doto (JMenu. "File")
-                            (.add (doto (JMenuItem. "New")
-                                    (.setAccelerator (KeyStroke/getKeyStroke KeyEvent/VK_N ActionEvent/CTRL_MASK))
-                                    (.addActionListener actionListener)))
-                            (.addSeparator)
-                            (.add (doto (JMenuItem. "Exit")
-                                    (.setAccelerator (KeyStroke/getKeyStroke KeyEvent/VK_Q, ActionEvent/CTRL_MASK))
-                                    (.addActionListener actionListener)))))))
+                          (.add (doto (JMenu. "File")
+                                  (.add (doto (JMenuItem. (make-action-new state))
+                                          (.setAccelerator (KeyStroke/getKeyStroke KeyEvent/VK_N ActionEvent/CTRL_MASK))))
+                                  (.addSeparator)
+                                  (.add (doto (JMenuItem. (make-action-exit))
+                                          (.setAccelerator (KeyStroke/getKeyStroke KeyEvent/VK_Q, ActionEvent/CTRL_MASK))))))))
+    (.addMouseListener content-pane mouse-adapter)
+    (.addMouseMotionListener content-pane mouse-adapter)
+    (.addMouseWheelListener content-pane mouse-adapter)
     (.setSize frame 800 800)
     (.setVisible frame true)
    ))
+
+
+(defn -main [& args]
+  (let [state (atom {})]
+    (reset-board! state)
+    (start-editor state)))
diff --git a/src/hulkure/utils.clj b/src/hulkure/utils.clj
index ab63b6e..4672a7f 100644
--- a/src/hulkure/utils.clj
+++ b/src/hulkure/utils.clj
@@ -1,4 +1,8 @@
 (ns hulkure.utils)
 
 (defn filter-first [pred coll]
-  (first (filter pred coll)))
\ No newline at end of file
+  (first (filter pred coll)))
+
+(defn removev [v index]
+  (vec (concat (subvec v 0 index)
+               (subvec v (inc index)))))
\ No newline at end of file