diff --git a/test-solve/src/commonMain/kotlin/it/unibo/tuprolog/solve/SolverTest.kt b/test-solve/src/commonMain/kotlin/it/unibo/tuprolog/solve/SolverTest.kt
index 117b5de30..b306078e9 100644
--- a/test-solve/src/commonMain/kotlin/it/unibo/tuprolog/solve/SolverTest.kt
+++ b/test-solve/src/commonMain/kotlin/it/unibo/tuprolog/solve/SolverTest.kt
@@ -45,7 +45,7 @@ interface SolverTest {
 
     /** A long test max duration */
     val longDuration: TimeDuration
-        get() = 2 * mediumDuration
+        get() = 4 * mediumDuration
 
     /** Test presence of correct built-ins */
     fun testBuiltinApi()
diff --git a/test-solve/src/commonMain/kotlin/it/unibo/tuprolog/solve/SolverTestImpl.kt b/test-solve/src/commonMain/kotlin/it/unibo/tuprolog/solve/SolverTestImpl.kt
index 4c4a64bc7..b29408c5c 100644
--- a/test-solve/src/commonMain/kotlin/it/unibo/tuprolog/solve/SolverTestImpl.kt
+++ b/test-solve/src/commonMain/kotlin/it/unibo/tuprolog/solve/SolverTestImpl.kt
@@ -937,7 +937,7 @@ internal class SolverTestImpl(private val solverFactory: SolverFactory) : Solver
 
             val query = "retract"("f"("X"))
 
-            val solutions = solver.solve(query, mediumDuration).toList()
+            val solutions = solver.solve(query, longDuration).toList()
 
             assertSolutionEquals(
                 ktListOf(
@@ -1115,7 +1115,7 @@ internal class SolverTestImpl(private val solverFactory: SolverFactory) : Solver
 
             var query = "retractall"("f"("X"))
 
-            var solutions = solver.solve(query, mediumDuration).toList()
+            var solutions = solver.solve(query, longDuration).toList()
 
             assertSolutionEquals(
                 ktListOf(