diff --git a/app/src/main/java/sudoku/App.java b/app/src/main/java/sudoku/App.java
deleted file mode 100644
index 6aa33d4..0000000
--- a/app/src/main/java/sudoku/App.java
+++ /dev/null
@@ -1,14 +0,0 @@
-/*
- * This Java source file was generated by the Gradle 'init' task.
- */
-package sudoku;
-
-public class App {
-    public String getGreeting() {
-        return "Hello World!";
-    }
-
-    public static void main(String[] args) {
-        System.out.println(new App().getGreeting());
-    }
-}
diff --git a/app/src/main/java/sudoku/Solver.java b/app/src/main/java/sudoku/Solver.java
new file mode 100644
index 0000000..bfc1d7c
--- /dev/null
+++ b/app/src/main/java/sudoku/Solver.java
@@ -0,0 +1,32 @@
+package sudoku;
+
+public class Solver implements SudokuSolver {
+    private int[][] board;
+
+    public Solver() {
+        board = new int[9][9];
+    }
+
+    public void setBoard(int[][] board) {
+        this.board = board;
+    }
+
+    public int[][] getBoard() {
+        return board;
+    }
+
+    public boolean solve() {
+    }
+
+    public Boolean isSolved() {
+    }
+
+    private boolean solve(int row, int col) {
+    }
+
+    public boolean legal(int row, int col, int nbr) {
+    }
+
+    public String toString() {
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/sudoku/SolverMain.java b/app/src/main/java/sudoku/SolverMain.java
new file mode 100644
index 0000000..76acdf9
--- /dev/null
+++ b/app/src/main/java/sudoku/SolverMain.java
@@ -0,0 +1,7 @@
+package sudoku;
+
+public class SolverMain {
+    public static void main(String[] args) {
+        System.out.println("Hello world!");
+    }
+}
diff --git a/app/src/main/java/sudoku/SudokuSolver.java b/app/src/main/java/sudoku/SudokuSolver.java
index 8f33998..2500328 100644
--- a/app/src/main/java/sudoku/SudokuSolver.java
+++ b/app/src/main/java/sudoku/SudokuSolver.java
@@ -1,14 +1,11 @@
 package sudoku;
 
-public interface SudokuSolver{
-    
-    // Work in progress
-
+public interface SudokuSolver {
     /**
-     * Set sudoku board, numbers 1-9 are fixed values, 0 is unsolved. 
+     * Set sudoku board, numbers 1-9 are fixed values, 0 is unsolved.
      */
     void setBoard(int[][] board);
-    
+
     /**
      * Get the sudoku board
      */
@@ -16,12 +13,14 @@ public interface SudokuSolver{
 
     /**
      * Solve soduko
+     * 
      * @return true if solution could be found
      */
     boolean solve();
 
     /**
      * Check if digit is legal on the current board
+     * 
      * @param row
      * @param col
      * @param nbr
diff --git a/app/src/test/java/sudoku/AppTest.java b/app/src/test/java/sudoku/AppTest.java
deleted file mode 100644
index d687b40..0000000
--- a/app/src/test/java/sudoku/AppTest.java
+++ /dev/null
@@ -1,14 +0,0 @@
-/*
- * This Java source file was generated by the Gradle 'init' task.
- */
-package sudoku;
-
-import org.junit.jupiter.api.Test;
-import static org.junit.jupiter.api.Assertions.*;
-
-class AppTest {
-    @Test void appHasAGreeting() {
-        App classUnderTest = new App();
-        assertNotNull(classUnderTest.getGreeting(), "app should have a greeting");
-    }
-}
diff --git a/app/src/test/java/sudoku/SolverTest.java b/app/src/test/java/sudoku/SolverTest.java
new file mode 100644
index 0000000..ae16b4b
--- /dev/null
+++ b/app/src/test/java/sudoku/SolverTest.java
@@ -0,0 +1,12 @@
+package sudoku;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+class SolverTest {
+    @Test void boardTest() {
+        Solver solver = new Solver();
+        solver.solve();
+        assertTrue(solver.isSolved());
+    }
+}