diff --git a/src/main/java/puzzle/SwedishGenerator.java b/src/main/java/puzzle/SwedishGenerator.java
index f8986bc..6a2123b 100644
--- a/src/main/java/puzzle/SwedishGenerator.java
+++ b/src/main/java/puzzle/SwedishGenerator.java
@@ -286,19 +286,18 @@ public record SwedishGenerator(Rng rng, int[] stack, Clues cache) {
       }
    }
    
-   static record Grid(byte[] g, long lo, long hi) {
+   @AllArgsConstructor
+   static class Grid {
       
-      public Grid(byte[] g)            { this(g, 0, 0); }
-      static Grid createEmpty()        { return new Grid(new byte[SIZE], X, X); }
-      public static int r(int offset)  { return offset & 7; }
-      public static int c(int offset)  { return offset >>> 3; }
-      static int offset(int r, int c)  { return r | (c << 3); }
+      final  byte[] g;
+      public long   lo, hi;
+      public static int r(int offset) { return offset & 7; }
+      public static int c(int offset) { return offset >>> 3; }
+      static int offset(int r, int c) { return r | (c << 3); }
       /// the pos will never target a clue
-      public byte letter32At(int pos)  { return g[pos]; }
+      public byte letter32At(int pos) { return g[pos]; }
       void setLetter(int idx, byte ch) { g[idx] = ch; }
       void clearletter(int idx)        { g[idx] = DASH; }
-      boolean isClue(int index)        { return ((index & 64) == 0) ? ((lo >>> index) & 1L) != X : ((hi >>> (index & 63)) & 1L) != X; }
-      boolean notClue(int index)       { return ((index & 64) == 0) ? ((lo >>> index) & 1L) == X : ((hi >>> (index & 63)) & 1L) == X; }
       
       void undoPlace(long maskLo, long maskHi) {
          for (long b = maskLo; b != 0; b &= b - 1) clearletter(Long.numberOfTrailingZeros(b));
diff --git a/src/test/java/puzzle/MainTest.java b/src/test/java/puzzle/MainTest.java
index 5c3b5df..417726e 100644
--- a/src/test/java/puzzle/MainTest.java
+++ b/src/test/java/puzzle/MainTest.java
@@ -102,27 +102,27 @@ public class MainTest {
       grid.setLetter(OFF_2_3, LETTER_Z);
       
       Assertions.assertEquals(LETTER_A, grid.letter32At(OFF_0_0));
-      Assertions.assertEquals(CLUE_UP, grid.letter32At(OFF_1_2));
+      Assertions.assertEquals(CLUE_UP, clues.digitAt(OFF_1_2));
       Assertions.assertEquals(LETTER_Z, grid.letter32At(OFF_2_3));
       Assertions.assertEquals(DASH, grid.letter32At(OFF_1_1));
       
       // Test isLetterAt
-      Assertions.assertTrue(grid.notClue(OFF_0_0));
-      Assertions.assertFalse(grid.notClue(OFF_1_2));
-      Assertions.assertTrue(grid.notClue(OFF_2_3));
-      Assertions.assertFalse(grid.isClue(OFF_1_1));
+      Assertions.assertTrue(clues.notClue(OFF_0_0));
+      Assertions.assertFalse(clues.notClue(OFF_1_2));
+      Assertions.assertTrue(clues.notClue(OFF_2_3));
+      Assertions.assertFalse(clues.isClue(OFF_1_1));
       
       // Test isDigitAt
-      Assertions.assertFalse(grid.isClue(0));
-      Assertions.assertTrue(grid.isClue(OFF_1_2));
+      Assertions.assertFalse(clues.isClue(0));
+      Assertions.assertTrue(clues.isClue(OFF_1_2));
       Assertions.assertEquals(CLUE_UP, clues.digitAt(OFF_1_2));
-      Assertions.assertFalse(grid.isClue(OFF_2_3));
-      Assertions.assertFalse(grid.isClue(OFF_1_1));
+      Assertions.assertFalse(clues.isClue(OFF_2_3));
+      Assertions.assertFalse(clues.isClue(OFF_1_1));
       
       // Test isLettercell
-      Assertions.assertTrue(grid.notClue(OFF_0_0)); // 'A' is letter
-      Assertions.assertTrue(grid.isClue(OFF_1_2)); // digit
-      Assertions.assertTrue(grid.notClue(OFF_1_1)); // '#' is lettercell
+      Assertions.assertTrue(clues.notClue(OFF_0_0)); // 'A' is letter
+      Assertions.assertTrue(clues.isClue(OFF_1_2)); // digit
+      Assertions.assertTrue(clues.notClue(OFF_1_1)); // '#' is lettercell
    }
    @Test
    public void testCluesDeepCopy() {
@@ -144,8 +144,7 @@ public class MainTest {
       val idx   = OFF_1_1;
       var clues = Clues.createEmpty();
       clues.setClue(idx, CLUE_LEFT);
-      var grid = clues.toGrid();
-      Assertions.assertTrue(grid.isClue(idx));
+      Assertions.assertTrue(clues.isClue(idx));
    }
    @Test
    void testMaskerCreation() {
@@ -179,8 +178,8 @@ public class MainTest {
       Assertions.assertTrue(filled.ok(), "Puzzle generation failed (not ok)");
       Assertions.assertEquals(18, filled.wordCount(), "Number of assigned words changed");
       Assertions.assertEquals("SLEDE", Lemma.asWord(filled.clueMap()[282]));
-      Assertions.assertEquals(74732156493031040L, filled.grid().grid().lo());
-      Assertions.assertEquals(193L, filled.grid().grid().hi());
+      Assertions.assertEquals(74732156493031040L, filled.grid().grid().lo);
+      Assertions.assertEquals(193L, filled.grid().grid().hi);
       
       var aa = new PuzzleResult(new Clued(mask), filled).exportFormatFromFilled(1, new Rewards(1, 1, 1));