diff --git a/domain/src/main/kotlin/ch/dissem/yaep/domain/generator.kt b/domain/src/main/kotlin/ch/dissem/yaep/domain/generator.kt
index 6660440..d4c0822 100644
--- a/domain/src/main/kotlin/ch/dissem/yaep/domain/generator.kt
+++ b/domain/src/main/kotlin/ch/dissem/yaep/domain/generator.kt
@@ -60,7 +60,20 @@ internal fun solve(
         } catch (e: UnsolvablePuzzleException) {
             return NO_SOLUTION
         }
-        // TODO clean up groups in rows (?)
+        // TODO: this breaks stuff and is probably unnecessary, but further tests might be needed
+//        grid.forEach { row -> row.forEach { cell -> row.cleanupOptions(cell) } }
+//        grid.forEach { row ->
+//            row.filter { it.selection == null && it.options.size in 2..row.size / 2 }
+//                .groupBy { cell -> cell.options }
+//                .filter { it.value.size == it.key.size }
+//                .forEach { entry ->
+//                    val groupOptions = entry.key
+//                    val group = entry.value
+//                    println("removing options for group ${groupOptions.map { it.symbol }}")
+//                    row.filter { !group.contains(it) }
+//                        .forEach { it.options.removeAll(groupOptions) }
+//                }
+//        }
         grid.forEach { row -> row.forEach { cell -> row.cleanupOptions(cell) } }
     } while (removedOptions)
 
diff --git a/domain/src/test/kotlin/ch/dissem/yaep/domain/GameTest.kt b/domain/src/test/kotlin/ch/dissem/yaep/domain/GameTest.kt
index fd2f23c..7baa59c 100644
--- a/domain/src/test/kotlin/ch/dissem/yaep/domain/GameTest.kt
+++ b/domain/src/test/kotlin/ch/dissem/yaep/domain/GameTest.kt
@@ -15,6 +15,47 @@ import kotlin.time.measureTime
 
 class GameTest {
 
+    @Test
+    fun `ensure generated games are solvable`() {
+        val tries = 2000
+        var fastest = 500.milliseconds
+        var slowest = 0.milliseconds
+        var total = 0.milliseconds
+        var most = 0
+        var least = 1000
+        var totalClues = 0
+        for (i in 1..tries) {
+            val game: Game
+            val time = measureTime {
+                game = generateGame()
+            }
+            expect(solve(game.grid, game.clues)).toEqual(SOLVABLE)
+            expect(time).toBeLessThan(500.milliseconds)
+            if (time < fastest) {
+                fastest = time
+            }
+            if (time > slowest) {
+                slowest = time
+            }
+            total += time
+            if (game.clues.size > most){
+                most = game.clues.size
+            }
+            if (game.clues.size < least){
+                least = game.clues.size
+            }
+            totalClues += game.clues.size
+        }
+
+        println("Slowest: $slowest")
+        println("Fastest: $fastest")
+        println("Average: ${total / tries}")
+        println("Clues:")
+        println("Most: $most")
+        println("Least: $least")
+        println("Average: ${totalClues / tries}")
+    }
+
     @Test
     fun `ensure generated game is valid`() {
         val game: Game