diff --git a/cffu-core/src/main/java/io/foldright/cffu/Cffu.java b/cffu-core/src/main/java/io/foldright/cffu/Cffu.java
index 85d12275..16188d58 100644
--- a/cffu-core/src/main/java/io/foldright/cffu/Cffu.java
+++ b/cffu-core/src/main/java/io/foldright/cffu/Cffu.java
@@ -15,8 +15,8 @@
 import java.util.concurrent.*;
 import java.util.function.*;
 
-import static io.foldright.cffu.CffuFactoryBuilder.cffuScreenedExecutor;
-import static io.foldright.cffu.CffuFactoryBuilder.cffuUnscreenedExecutor;
+import static io.foldright.cffu.CffuFactoryBuilder.cffuScreened;
+import static io.foldright.cffu.CffuFactoryBuilder.cffuUnscreened;
 import static java.util.Objects.requireNonNull;
 
 
@@ -120,7 +120,7 @@ public <U> Cffu<U> thenApplyAsync(Function<? super T, ? extends U> fn) {
     @CheckReturnValue(explanation = "should use the returned Cffu; otherwise, prefer method `thenAcceptAsync`")
     @Override
     public <U> Cffu<U> thenApplyAsync(Function<? super T, ? extends U> fn, Executor executor) {
-        return resetCf(cf.thenApplyAsync(fn, cffuScreenedExecutor(executor)));
+        return resetCf(cf.thenApplyAsync(fn, cffuScreened(executor)));
     }
 
     /**
@@ -161,7 +161,7 @@ public Cffu<Void> thenAcceptAsync(Consumer<? super T> action) {
      */
     @Override
     public Cffu<Void> thenAcceptAsync(Consumer<? super T> action, Executor executor) {
-        return resetCf(cf.thenAcceptAsync(action, cffuScreenedExecutor(executor)));
+        return resetCf(cf.thenAcceptAsync(action, cffuScreened(executor)));
     }
 
     /**
@@ -199,7 +199,7 @@ public Cffu<Void> thenRunAsync(Runnable action) {
      */
     @Override
     public Cffu<Void> thenRunAsync(Runnable action, Executor executor) {
-        return resetCf(cf.thenRunAsync(action, cffuScreenedExecutor(executor)));
+        return resetCf(cf.thenRunAsync(action, cffuScreened(executor)));
     }
 
     // endregion
@@ -237,7 +237,7 @@ public final <U> Cffu<List<U>> thenMApplyFailFastAsync(Function<? super T, ? ext
      */
     @SafeVarargs
     public final <U> Cffu<List<U>> thenMApplyFailFastAsync(Executor executor, Function<? super T, ? extends U>... fns) {
-        return resetCf(CompletableFutureUtils.thenMApplyFailFastAsync(cf, cffuScreenedExecutor(executor), fns));
+        return resetCf(CompletableFutureUtils.thenMApplyFailFastAsync(cf, cffuScreened(executor), fns));
     }
 
     /**
@@ -268,7 +268,7 @@ public final <U> Cffu<List<U>> thenMApplyAllSuccessAsync(
     @SafeVarargs
     public final <U> Cffu<List<U>> thenMApplyAllSuccessAsync(
             Executor executor, @Nullable U valueIfFailed, Function<? super T, ? extends U>... fns) {
-        return resetCf(CompletableFutureUtils.thenMApplyAllSuccessAsync(cf, cffuScreenedExecutor(executor), valueIfFailed, fns));
+        return resetCf(CompletableFutureUtils.thenMApplyAllSuccessAsync(cf, cffuScreened(executor), valueIfFailed, fns));
     }
 
     /**
@@ -295,7 +295,8 @@ public final <U> Cffu<List<U>> thenMApplyMostSuccessAsync(
     public final <U> Cffu<List<U>> thenMApplyMostSuccessAsync(
             Executor executor, @Nullable U valueIfNotSuccess, long timeout, TimeUnit unit,
             Function<? super T, ? extends U>... fns) {
-        return resetCf(CompletableFutureUtils.thenMApplyMostSuccessAsync(cf, cffuScreenedExecutor(executor), valueIfNotSuccess, timeout, unit, fns));
+        return resetCf(CompletableFutureUtils.thenMApplyMostSuccessAsync(
+                cf, cffuScreened(executor), valueIfNotSuccess, timeout, unit, fns));
     }
 
     /**
@@ -322,7 +323,7 @@ public final <U> Cffu<List<U>> thenMApplyAsync(Function<? super T, ? extends U>.
      */
     @SafeVarargs
     public final <U> Cffu<List<U>> thenMApplyAsync(Executor executor, Function<? super T, ? extends U>... fns) {
-        return resetCf(CompletableFutureUtils.thenMApplyAsync(cf, cffuScreenedExecutor(executor), fns));
+        return resetCf(CompletableFutureUtils.thenMApplyAsync(cf, cffuScreened(executor), fns));
     }
 
     /**
@@ -349,7 +350,7 @@ public final <U> Cffu<U> thenMApplyAnySuccessAsync(Function<? super T, ? extends
      */
     @SafeVarargs
     public final <U> Cffu<U> thenMApplyAnySuccessAsync(Executor executor, Function<? super T, ? extends U>... fns) {
-        return resetCf(CompletableFutureUtils.thenMApplyAnySuccessAsync(cf, cffuScreenedExecutor(executor), fns));
+        return resetCf(CompletableFutureUtils.thenMApplyAnySuccessAsync(cf, cffuScreened(executor), fns));
     }
 
     /**
@@ -376,7 +377,7 @@ public final <U> Cffu<U> thenMApplyAnyAsync(Function<? super T, ? extends U>...
      */
     @SafeVarargs
     public final <U> Cffu<U> thenMApplyAnyAsync(Executor executor, Function<? super T, ? extends U>... fns) {
-        return resetCf(CompletableFutureUtils.thenMApplyAnyAsync(cf, cffuScreenedExecutor(executor), fns));
+        return resetCf(CompletableFutureUtils.thenMApplyAnyAsync(cf, cffuScreened(executor), fns));
     }
 
     /**
@@ -408,7 +409,7 @@ public final Cffu<Void> thenMAcceptFailFastAsync(Consumer<? super T>... actions)
      */
     @SafeVarargs
     public final Cffu<Void> thenMAcceptFailFastAsync(Executor executor, Consumer<? super T>... actions) {
-        return resetCf(CompletableFutureUtils.thenMAcceptFailFastAsync(cf, cffuScreenedExecutor(executor), actions));
+        return resetCf(CompletableFutureUtils.thenMAcceptFailFastAsync(cf, cffuScreened(executor), actions));
     }
 
     /**
@@ -440,7 +441,7 @@ public final Cffu<Void> thenMAcceptAsync(Consumer<? super T>... actions) {
      */
     @SafeVarargs
     public final Cffu<Void> thenMAcceptAsync(Executor executor, Consumer<? super T>... actions) {
-        return resetCf(CompletableFutureUtils.thenMAcceptAsync(cf, cffuScreenedExecutor(executor), actions));
+        return resetCf(CompletableFutureUtils.thenMAcceptAsync(cf, cffuScreened(executor), actions));
     }
 
     /**
@@ -472,7 +473,7 @@ public final Cffu<Void> thenMAcceptAnySuccessAsync(Consumer<? super T>... action
      */
     @SafeVarargs
     public final Cffu<Void> thenMAcceptAnySuccessAsync(Executor executor, Consumer<? super T>... actions) {
-        return resetCf(CompletableFutureUtils.thenMAcceptAnySuccessAsync(cf, cffuScreenedExecutor(executor), actions));
+        return resetCf(CompletableFutureUtils.thenMAcceptAnySuccessAsync(cf, cffuScreened(executor), actions));
     }
 
     /**
@@ -504,7 +505,7 @@ public final Cffu<Void> thenMAcceptAnyAsync(Consumer<? super T>... actions) {
      */
     @SafeVarargs
     public final Cffu<Void> thenMAcceptAnyAsync(Executor executor, Consumer<? super T>... actions) {
-        return resetCf(CompletableFutureUtils.thenMAcceptAnyAsync(cf, cffuScreenedExecutor(executor), actions));
+        return resetCf(CompletableFutureUtils.thenMAcceptAnyAsync(cf, cffuScreened(executor), actions));
     }
 
     /**
@@ -524,7 +525,7 @@ public Cffu<Void> thenMRunFailFastAsync(Runnable... actions) {
      * See the {@link CffuFactory#allFailFastOf allFailFastOf} documentation for the rules of result computation.
      */
     public Cffu<Void> thenMRunFailFastAsync(Executor executor, Runnable... actions) {
-        return resetCf(CompletableFutureUtils.thenMRunFailFastAsync(cf, cffuScreenedExecutor(executor), actions));
+        return resetCf(CompletableFutureUtils.thenMRunFailFastAsync(cf, cffuScreened(executor), actions));
     }
 
     /**
@@ -544,7 +545,7 @@ public Cffu<Void> thenMRunAsync(Runnable... actions) {
      * See the {@link CffuFactory#allOf allOf} documentation for the rules of result computation.
      */
     public Cffu<Void> thenMRunAsync(Executor executor, Runnable... actions) {
-        return resetCf(CompletableFutureUtils.thenMRunAsync(cf, cffuScreenedExecutor(executor), actions));
+        return resetCf(CompletableFutureUtils.thenMRunAsync(cf, cffuScreened(executor), actions));
     }
 
     /**
@@ -564,7 +565,7 @@ public Cffu<Void> thenMRunAnySuccessAsync(Runnable... actions) {
      * See the {@link CffuFactory#anySuccessOf anySuccessOf} documentation for the rules of result computation.
      */
     public Cffu<Void> thenMRunAnySuccessAsync(Executor executor, Runnable... actions) {
-        return resetCf(CompletableFutureUtils.thenMRunAnySuccessAsync(cf, cffuScreenedExecutor(executor), actions));
+        return resetCf(CompletableFutureUtils.thenMRunAnySuccessAsync(cf, cffuScreened(executor), actions));
     }
 
     /**
@@ -584,7 +585,7 @@ public Cffu<Void> thenMRunAnyAsync(Runnable... actions) {
      * See the {@link CffuFactory#anyOf anyOf} documentation for the rules of result computation.
      */
     public Cffu<Void> thenMRunAnyAsync(Executor executor, Runnable... actions) {
-        return resetCf(CompletableFutureUtils.thenMRunAnyAsync(cf, cffuScreenedExecutor(executor), actions));
+        return resetCf(CompletableFutureUtils.thenMRunAnyAsync(cf, cffuScreened(executor), actions));
     }
 
     // endregion
@@ -605,7 +606,7 @@ public <U1, U2> Cffu<Tuple2<U1, U2>> thenMApplyTupleFailFastAsync(
      */
     public <U1, U2> Cffu<Tuple2<U1, U2>> thenMApplyTupleFailFastAsync(
             Executor executor, Function<? super T, ? extends U1> fn1, Function<? super T, ? extends U2> fn2) {
-        return resetCf(CompletableFutureUtils.thenMApplyTupleFailFastAsync(cf, cffuScreenedExecutor(executor), fn1, fn2));
+        return resetCf(CompletableFutureUtils.thenMApplyTupleFailFastAsync(cf, cffuScreened(executor), fn1, fn2));
     }
 
     /**
@@ -623,7 +624,7 @@ public <U1, U2, U3> Cffu<Tuple3<U1, U2, U3>> thenMApplyTupleFailFastAsync(
     public <U1, U2, U3> Cffu<Tuple3<U1, U2, U3>> thenMApplyTupleFailFastAsync(
             Executor executor, Function<? super T, ? extends U1> fn1,
             Function<? super T, ? extends U2> fn2, Function<? super T, ? extends U3> fn3) {
-        return resetCf(CompletableFutureUtils.thenMApplyTupleFailFastAsync(cf, cffuScreenedExecutor(executor), fn1, fn2, fn3));
+        return resetCf(CompletableFutureUtils.thenMApplyTupleFailFastAsync(cf, cffuScreened(executor), fn1, fn2, fn3));
     }
 
     /**
@@ -641,7 +642,7 @@ public <U1, U2, U3, U4> Cffu<Tuple4<U1, U2, U3, U4>> thenMApplyTupleFailFastAsyn
     public <U1, U2, U3, U4> Cffu<Tuple4<U1, U2, U3, U4>> thenMApplyTupleFailFastAsync(
             Executor executor, Function<? super T, ? extends U1> fn1, Function<? super T, ? extends U2> fn2,
             Function<? super T, ? extends U3> fn3, Function<? super T, ? extends U4> fn4) {
-        return resetCf(CompletableFutureUtils.thenMApplyTupleFailFastAsync(cf, cffuScreenedExecutor(executor), fn1, fn2, fn3, fn4));
+        return resetCf(CompletableFutureUtils.thenMApplyTupleFailFastAsync(cf, cffuScreened(executor), fn1, fn2, fn3, fn4));
     }
 
     /**
@@ -661,7 +662,7 @@ public <U1, U2, U3, U4, U5> Cffu<Tuple5<U1, U2, U3, U4, U5>> thenMApplyTupleFail
             Executor executor, Function<? super T, ? extends U1> fn1,
             Function<? super T, ? extends U2> fn2, Function<? super T, ? extends U3> fn3,
             Function<? super T, ? extends U4> fn4, Function<? super T, ? extends U5> fn5) {
-        return resetCf(CompletableFutureUtils.thenMApplyTupleFailFastAsync(cf, cffuScreenedExecutor(executor), fn1, fn2, fn3, fn4, fn5));
+        return resetCf(CompletableFutureUtils.thenMApplyTupleFailFastAsync(cf, cffuScreened(executor), fn1, fn2, fn3, fn4, fn5));
     }
 
     /**
@@ -683,7 +684,7 @@ public <U1, U2> Cffu<Tuple2<U1, U2>> thenMApplyAllSuccessTupleAsync(
      */
     public <U1, U2> Cffu<Tuple2<U1, U2>> thenMApplyAllSuccessTupleAsync(
             Executor executor, Function<? super T, ? extends U1> fn1, Function<? super T, ? extends U2> fn2) {
-        return resetCf(CompletableFutureUtils.thenMApplyAllSuccessTupleAsync(cf, cffuScreenedExecutor(executor), fn1, fn2));
+        return resetCf(CompletableFutureUtils.thenMApplyAllSuccessTupleAsync(cf, cffuScreened(executor), fn1, fn2));
     }
 
     /**
@@ -707,7 +708,7 @@ public <U1, U2, U3> Cffu<Tuple3<U1, U2, U3>> thenMApplyAllSuccessTupleAsync(
     public <U1, U2, U3> Cffu<Tuple3<U1, U2, U3>> thenMApplyAllSuccessTupleAsync(
             Executor executor, Function<? super T, ? extends U1> fn1,
             Function<? super T, ? extends U2> fn2, Function<? super T, ? extends U3> fn3) {
-        return resetCf(CompletableFutureUtils.thenMApplyAllSuccessTupleAsync(cf, cffuScreenedExecutor(executor), fn1, fn2, fn3));
+        return resetCf(CompletableFutureUtils.thenMApplyAllSuccessTupleAsync(cf, cffuScreened(executor), fn1, fn2, fn3));
     }
 
     /**
@@ -731,7 +732,7 @@ public <U1, U2, U3, U4> Cffu<Tuple4<U1, U2, U3, U4>> thenMApplyAllSuccessTupleAs
     public <U1, U2, U3, U4> Cffu<Tuple4<U1, U2, U3, U4>> thenMApplyAllSuccessTupleAsync(
             Executor executor, Function<? super T, ? extends U1> fn1, Function<? super T, ? extends U2> fn2,
             Function<? super T, ? extends U3> fn3, Function<? super T, ? extends U4> fn4) {
-        return resetCf(CompletableFutureUtils.thenMApplyAllSuccessTupleAsync(cf, cffuScreenedExecutor(executor), fn1, fn2, fn3, fn4));
+        return resetCf(CompletableFutureUtils.thenMApplyAllSuccessTupleAsync(cf, cffuScreened(executor), fn1, fn2, fn3, fn4));
     }
 
     /**
@@ -757,7 +758,7 @@ public <U1, U2, U3, U4, U5> Cffu<Tuple5<U1, U2, U3, U4, U5>> thenMApplyAllSucces
             Executor executor, Function<? super T, ? extends U1> fn1,
             Function<? super T, ? extends U2> fn2, Function<? super T, ? extends U3> fn3,
             Function<? super T, ? extends U4> fn4, Function<? super T, ? extends U5> fn5) {
-        return resetCf(CompletableFutureUtils.thenMApplyAllSuccessTupleAsync(cf, cffuScreenedExecutor(executor), fn1, fn2, fn3, fn4, fn5));
+        return resetCf(CompletableFutureUtils.thenMApplyAllSuccessTupleAsync(cf, cffuScreened(executor), fn1, fn2, fn3, fn4, fn5));
     }
 
     /**
@@ -782,7 +783,8 @@ public <U1, U2> Cffu<Tuple2<U1, U2>> thenMApplyMostSuccessTupleAsync(
     public <U1, U2> Cffu<Tuple2<U1, U2>> thenMApplyMostSuccessTupleAsync(
             Executor executor, long timeout, TimeUnit unit,
             Function<? super T, ? extends U1> fn1, Function<? super T, ? extends U2> fn2) {
-        return resetCf(CompletableFutureUtils.thenMApplyMostSuccessTupleAsync(cf, cffuScreenedExecutor(executor), timeout, unit, fn1, fn2));
+        return resetCf(CompletableFutureUtils.thenMApplyMostSuccessTupleAsync(
+                cf, cffuScreened(executor), timeout, unit, fn1, fn2));
     }
 
     /**
@@ -808,7 +810,8 @@ public <U1, U2, U3> Cffu<Tuple3<U1, U2, U3>> thenMApplyMostSuccessTupleAsync(
     public <U1, U2, U3> Cffu<Tuple3<U1, U2, U3>> thenMApplyMostSuccessTupleAsync(
             Executor executor, long timeout, TimeUnit unit, Function<? super T, ? extends U1> fn1,
             Function<? super T, ? extends U2> fn2, Function<? super T, ? extends U3> fn3) {
-        return resetCf(CompletableFutureUtils.thenMApplyMostSuccessTupleAsync(cf, cffuScreenedExecutor(executor), timeout, unit, fn1, fn2, fn3));
+        return resetCf(CompletableFutureUtils.thenMApplyMostSuccessTupleAsync(
+                cf, cffuScreened(executor), timeout, unit, fn1, fn2, fn3));
     }
 
     /**
@@ -836,7 +839,8 @@ public <U1, U2, U3, U4> Cffu<Tuple4<U1, U2, U3, U4>> thenMApplyMostSuccessTupleA
             Executor executor, long timeout, TimeUnit unit,
             Function<? super T, ? extends U1> fn1, Function<? super T, ? extends U2> fn2,
             Function<? super T, ? extends U3> fn3, Function<? super T, ? extends U4> fn4) {
-        return resetCf(CompletableFutureUtils.thenMApplyMostSuccessTupleAsync(cf, cffuScreenedExecutor(executor), timeout, unit, fn1, fn2, fn3, fn4));
+        return resetCf(CompletableFutureUtils.thenMApplyMostSuccessTupleAsync(
+                cf, cffuScreened(executor), timeout, unit, fn1, fn2, fn3, fn4));
     }
 
     /**
@@ -865,7 +869,7 @@ public <U1, U2, U3, U4, U5> Cffu<Tuple5<U1, U2, U3, U4, U5>> thenMApplyMostSucce
             Function<? super T, ? extends U2> fn2, Function<? super T, ? extends U3> fn3,
             Function<? super T, ? extends U4> fn4, Function<? super T, ? extends U5> fn5) {
         return resetCf(CompletableFutureUtils.thenMApplyMostSuccessTupleAsync(
-                cf, cffuScreenedExecutor(executor), timeout, unit, fn1, fn2, fn3, fn4, fn5));
+                cf, cffuScreened(executor), timeout, unit, fn1, fn2, fn3, fn4, fn5));
     }
 
     /**
@@ -881,7 +885,7 @@ public <U1, U2> Cffu<Tuple2<U1, U2>> thenMApplyTupleAsync(
      */
     public <U1, U2> Cffu<Tuple2<U1, U2>> thenMApplyTupleAsync(
             Executor executor, Function<? super T, ? extends U1> fn1, Function<? super T, ? extends U2> fn2) {
-        return resetCf(CompletableFutureUtils.thenMApplyTupleAsync(cf, cffuScreenedExecutor(executor), fn1, fn2));
+        return resetCf(CompletableFutureUtils.thenMApplyTupleAsync(cf, cffuScreened(executor), fn1, fn2));
     }
 
     /**
@@ -899,7 +903,7 @@ public <U1, U2, U3> Cffu<Tuple3<U1, U2, U3>> thenMApplyTupleAsync(
     public <U1, U2, U3> Cffu<Tuple3<U1, U2, U3>> thenMApplyTupleAsync(
             Executor executor, Function<? super T, ? extends U1> fn1, Function<? super T, ? extends U2> fn2,
             Function<? super T, ? extends U3> fn3) {
-        return resetCf(CompletableFutureUtils.thenMApplyTupleAsync(cf, cffuScreenedExecutor(executor), fn1, fn2, fn3));
+        return resetCf(CompletableFutureUtils.thenMApplyTupleAsync(cf, cffuScreened(executor), fn1, fn2, fn3));
     }
 
     /**
@@ -917,7 +921,7 @@ public <U1, U2, U3, U4> Cffu<Tuple4<U1, U2, U3, U4>> thenMApplyTupleAsync(
     public <U1, U2, U3, U4> Cffu<Tuple4<U1, U2, U3, U4>> thenMApplyTupleAsync(
             Executor executor, Function<? super T, ? extends U1> fn1, Function<? super T, ? extends U2> fn2,
             Function<? super T, ? extends U3> fn3, Function<? super T, ? extends U4> fn4) {
-        return resetCf(CompletableFutureUtils.thenMApplyTupleAsync(cf, cffuScreenedExecutor(executor), fn1, fn2, fn3, fn4));
+        return resetCf(CompletableFutureUtils.thenMApplyTupleAsync(cf, cffuScreened(executor), fn1, fn2, fn3, fn4));
     }
 
     /**
@@ -937,7 +941,7 @@ public <U1, U2, U3, U4, U5> Cffu<Tuple5<U1, U2, U3, U4, U5>> thenMApplyTupleAsyn
             Executor executor, Function<? super T, ? extends U1> fn1, Function<? super T, ? extends U2> fn2,
             Function<? super T, ? extends U3> fn3, Function<? super T, ? extends U4> fn4,
             Function<? super T, ? extends U5> fn5) {
-        return resetCf(CompletableFutureUtils.thenMApplyTupleAsync(cf, cffuScreenedExecutor(executor), fn1, fn2, fn3, fn4, fn5));
+        return resetCf(CompletableFutureUtils.thenMApplyTupleAsync(cf, cffuScreened(executor), fn1, fn2, fn3, fn4, fn5));
     }
 
     // endregion
@@ -1001,7 +1005,7 @@ public <U, V> Cffu<V> thenCombineFailFastAsync(
     @CheckReturnValue(explanation = "should use the returned Cffu; otherwise, prefer method `thenAcceptBothFailFastAsync`")
     public <U, V> Cffu<V> thenCombineFailFastAsync(
             CompletionStage<? extends U> other, BiFunction<? super T, ? super U, ? extends V> fn, Executor executor) {
-        return resetCf(CompletableFutureUtils.thenCombineFailFastAsync(cf, other, fn, cffuScreenedExecutor(executor)));
+        return resetCf(CompletableFutureUtils.thenCombineFailFastAsync(cf, other, fn, cffuScreened(executor)));
     }
 
     /**
@@ -1050,7 +1054,7 @@ public <U> Cffu<Void> thenAcceptBothFailFastAsync(
      */
     public <U> Cffu<Void> thenAcceptBothFailFastAsync(
             CompletionStage<? extends U> other, BiConsumer<? super T, ? super U> action, Executor executor) {
-        return resetCf(CompletableFutureUtils.thenAcceptBothFailFastAsync(cf, other, action, cffuScreenedExecutor(executor)));
+        return resetCf(CompletableFutureUtils.thenAcceptBothFailFastAsync(cf, other, action, cffuScreened(executor)));
     }
 
     /**
@@ -1092,7 +1096,7 @@ public Cffu<Void> runAfterBothFailFastAsync(CompletionStage<?> other, Runnable a
      * @param executor the executor to use for asynchronous execution
      */
     public Cffu<Void> runAfterBothFailFastAsync(CompletionStage<?> other, Runnable action, Executor executor) {
-        return resetCf(CompletableFutureUtils.runAfterBothFailFastAsync(cf, other, action, cffuScreenedExecutor(executor)));
+        return resetCf(CompletableFutureUtils.runAfterBothFailFastAsync(cf, other, action, cffuScreened(executor)));
     }
 
     /**
@@ -1147,7 +1151,7 @@ public <U, V> Cffu<V> thenCombineAsync(
     @Override
     public <U, V> Cffu<V> thenCombineAsync(
             CompletionStage<? extends U> other, BiFunction<? super T, ? super U, ? extends V> fn, Executor executor) {
-        return resetCf(cf.thenCombineAsync(other, fn, cffuScreenedExecutor(executor)));
+        return resetCf(cf.thenCombineAsync(other, fn, cffuScreened(executor)));
     }
 
     /**
@@ -1196,7 +1200,7 @@ public <U> Cffu<Void> thenAcceptBothAsync(
     @Override
     public <U> Cffu<Void> thenAcceptBothAsync(
             CompletionStage<? extends U> other, BiConsumer<? super T, ? super U> action, Executor executor) {
-        return resetCf(cf.thenAcceptBothAsync(other, action, cffuScreenedExecutor(executor)));
+        return resetCf(cf.thenAcceptBothAsync(other, action, cffuScreened(executor)));
     }
 
     /**
@@ -1239,7 +1243,7 @@ public Cffu<Void> runAfterBothAsync(CompletionStage<?> other, Runnable action) {
      */
     @Override
     public Cffu<Void> runAfterBothAsync(CompletionStage<?> other, Runnable action, Executor executor) {
-        return resetCf(cf.runAfterBothAsync(other, action, cffuScreenedExecutor(executor)));
+        return resetCf(cf.runAfterBothAsync(other, action, cffuScreened(executor)));
     }
 
     // endregion
@@ -1290,7 +1294,7 @@ public <U> Cffu<U> applyToEitherSuccessAsync(CompletionStage<? extends T> other,
     @CheckReturnValue(explanation = "should use the returned Cffu; otherwise, prefer method `acceptEitherSuccessAsync`")
     public <U> Cffu<U> applyToEitherSuccessAsync(
             CompletionStage<? extends T> other, Function<? super T, U> fn, Executor executor) {
-        return resetCf(CompletableFutureUtils.applyToEitherSuccessAsync(cf, other, fn, cffuScreenedExecutor(executor)));
+        return resetCf(CompletableFutureUtils.applyToEitherSuccessAsync(cf, other, fn, cffuScreened(executor)));
     }
 
     /**
@@ -1326,7 +1330,7 @@ public Cffu<Void> acceptEitherSuccessAsync(CompletionStage<? extends T> other, C
      */
     public Cffu<Void> acceptEitherSuccessAsync(
             CompletionStage<? extends T> other, Consumer<? super T> action, Executor executor) {
-        return resetCf(CompletableFutureUtils.acceptEitherSuccessAsync(cf, other, action, cffuScreenedExecutor(executor)));
+        return resetCf(CompletableFutureUtils.acceptEitherSuccessAsync(cf, other, action, cffuScreened(executor)));
     }
 
     /**
@@ -1365,7 +1369,7 @@ public Cffu<Void> runAfterEitherSuccessAsync(CompletionStage<?> other, Runnable
      * @param executor the executor to use for asynchronous execution
      */
     public Cffu<Void> runAfterEitherSuccessAsync(CompletionStage<?> other, Runnable action, Executor executor) {
-        return resetCf(CompletableFutureUtils.runAfterEitherSuccessAsync(cf, other, action, cffuScreenedExecutor(executor)));
+        return resetCf(CompletableFutureUtils.runAfterEitherSuccessAsync(cf, other, action, cffuScreened(executor)));
     }
 
     /**
@@ -1416,7 +1420,7 @@ public <U> Cffu<U> applyToEitherAsync(CompletionStage<? extends T> other, Functi
     @Override
     public <U> Cffu<U> applyToEitherAsync(
             CompletionStage<? extends T> other, Function<? super T, U> fn, Executor executor) {
-        return resetCf(cf.applyToEitherAsync(other, fn, cffuScreenedExecutor(executor)));
+        return resetCf(cf.applyToEitherAsync(other, fn, cffuScreened(executor)));
     }
 
     /**
@@ -1461,7 +1465,7 @@ public Cffu<Void> acceptEitherAsync(CompletionStage<? extends T> other, Consumer
     @Override
     public Cffu<Void> acceptEitherAsync(
             CompletionStage<? extends T> other, Consumer<? super T> action, Executor executor) {
-        return resetCf(cf.acceptEitherAsync(other, action, cffuScreenedExecutor(executor)));
+        return resetCf(cf.acceptEitherAsync(other, action, cffuScreened(executor)));
     }
 
     /**
@@ -1504,7 +1508,7 @@ public Cffu<Void> runAfterEitherAsync(CompletionStage<?> other, Runnable action)
      */
     @Override
     public Cffu<Void> runAfterEitherAsync(CompletionStage<?> other, Runnable action, Executor executor) {
-        return resetCf(cf.runAfterEitherAsync(other, action, cffuScreenedExecutor(executor)));
+        return resetCf(cf.runAfterEitherAsync(other, action, cffuScreened(executor)));
     }
 
     // endregion
@@ -1575,7 +1579,7 @@ public <X extends Throwable> Cffu<T> catchingAsync(
      */
     public <X extends Throwable> Cffu<T> catchingAsync(
             Class<X> exceptionType, Function<? super X, ? extends T> fallback, Executor executor) {
-        return resetCf(CompletableFutureUtils.catchingAsync(cf, exceptionType, fallback, cffuScreenedExecutor(executor)));
+        return resetCf(CompletableFutureUtils.catchingAsync(cf, exceptionType, fallback, cffuScreened(executor)));
     }
 
     /**
@@ -1634,7 +1638,7 @@ public Cffu<T> exceptionallyAsync(Function<Throwable, ? extends T> fn) {
      */
     @Override
     public Cffu<T> exceptionallyAsync(Function<Throwable, ? extends T> fn, Executor executor) {
-        return resetCf(CompletableFutureUtils.exceptionallyAsync(cf, fn, cffuScreenedExecutor(executor)));
+        return resetCf(CompletableFutureUtils.exceptionallyAsync(cf, fn, cffuScreened(executor)));
     }
 
     // endregion
@@ -1660,7 +1664,7 @@ public Cffu<T> exceptionallyAsync(Function<Throwable, ? extends T> fn, Executor
      */
     public Cffu<T> orTimeout(long timeout, TimeUnit unit) {
         checkMinimalStage();
-        return resetCf(CompletableFutureUtils.cffuOrTimeout(cf, timeout, unit, cffuScreenedExecutor(fac.cffuExecutor)));
+        return resetCf(CompletableFutureUtils.cffuOrTimeout(cf, timeout, unit, cffuScreened(fac.cffuExecutor)));
     }
 
     /**
@@ -1717,7 +1721,7 @@ public Cffu<T> unsafeOrTimeout(long timeout, TimeUnit unit) {
      */
     public Cffu<T> completeOnTimeout(@Nullable T value, long timeout, TimeUnit unit) {
         checkMinimalStage();
-        return resetCf(CompletableFutureUtils.cffuCompleteOnTimeout(cf, value, timeout, unit, cffuScreenedExecutor(fac.cffuExecutor)));
+        return resetCf(CompletableFutureUtils.cffuCompleteOnTimeout(cf, value, timeout, unit, cffuScreened(fac.cffuExecutor)));
     }
 
     /**
@@ -1819,7 +1823,7 @@ public <U> Cffu<U> thenComposeAsync(Function<? super T, ? extends CompletionStag
      */
     @Override
     public <U> Cffu<U> thenComposeAsync(Function<? super T, ? extends CompletionStage<U>> fn, Executor executor) {
-        return resetCf(cf.thenComposeAsync(fn, cffuScreenedExecutor(executor)));
+        return resetCf(cf.thenComposeAsync(fn, cffuScreened(executor)));
     }
 
     /**
@@ -1883,7 +1887,7 @@ public <X extends Throwable> Cffu<T> catchingComposeAsync(
      */
     public <X extends Throwable> Cffu<T> catchingComposeAsync(
             Class<X> exceptionType, Function<? super X, ? extends CompletionStage<T>> fallback, Executor executor) {
-        return resetCf(CompletableFutureUtils.catchingComposeAsync(cf, exceptionType, fallback, cffuScreenedExecutor(executor)));
+        return resetCf(CompletableFutureUtils.catchingComposeAsync(cf, exceptionType, fallback, cffuScreened(executor)));
     }
 
     /**
@@ -1937,7 +1941,7 @@ public Cffu<T> exceptionallyComposeAsync(Function<Throwable, ? extends Completio
      */
     @Override
     public Cffu<T> exceptionallyComposeAsync(Function<Throwable, ? extends CompletionStage<T>> fn, Executor executor) {
-        return resetCf(CompletableFutureUtils.exceptionallyComposeAsync(cf, fn, cffuScreenedExecutor(executor)));
+        return resetCf(CompletableFutureUtils.exceptionallyComposeAsync(cf, fn, cffuScreened(executor)));
     }
 
     /**
@@ -1991,7 +1995,7 @@ public <U> Cffu<U> handleAsync(BiFunction<? super T, Throwable, ? extends U> fn)
     @CheckReturnValue(explanation = "should use the returned Cffu; otherwise, prefer method `peekAsync`")
     @Override
     public <U> Cffu<U> handleAsync(BiFunction<? super T, Throwable, ? extends U> fn, Executor executor) {
-        return resetCf(cf.handleAsync(fn, cffuScreenedExecutor(executor)));
+        return resetCf(cf.handleAsync(fn, cffuScreened(executor)));
     }
 
     /**
@@ -2064,7 +2068,7 @@ public Cffu<T> whenCompleteAsync(BiConsumer<? super T, ? super Throwable> action
     @CheckReturnValue(explanation = "should use the returned Cffu; otherwise, prefer method `peekAsync`")
     @Override
     public Cffu<T> whenCompleteAsync(BiConsumer<? super T, ? super Throwable> action, Executor executor) {
-        return resetCf(cf.whenCompleteAsync(action, cffuScreenedExecutor(executor)));
+        return resetCf(cf.whenCompleteAsync(action, cffuScreened(executor)));
     }
 
     /**
@@ -2145,7 +2149,7 @@ public Cffu<T> peekAsync(BiConsumer<? super T, ? super Throwable> action) {
      */
     @Contract("_, _ -> this")
     public Cffu<T> peekAsync(BiConsumer<? super T, ? super Throwable> action, Executor executor) {
-        CompletableFutureUtils.peekAsync(cf, action, cffuScreenedExecutor(executor));
+        CompletableFutureUtils.peekAsync(cf, action, cffuScreened(executor));
         return this;
     }
 
@@ -2451,7 +2455,7 @@ public Cffu<T> completeAsync(Supplier<? extends T> supplier) {
     public Cffu<T> completeAsync(Supplier<? extends T> supplier, Executor executor) {
         checkMinimalStage();
         // NOTE: do NOT translate executor to screened executor; same as CompletableFuture.completeAsync
-        CompletableFutureUtils.completeAsync(cf, supplier, cffuUnscreenedExecutor(executor));
+        CompletableFutureUtils.completeAsync(cf, supplier, cffuUnscreened(executor));
         return this;
     }
 
@@ -2490,7 +2494,7 @@ public Cffu<T> completeExceptionallyAsync(Supplier<? extends Throwable> supplier
     public Cffu<T> completeExceptionallyAsync(Supplier<? extends Throwable> supplier, Executor executor) {
         checkMinimalStage();
         // NOTE: do NOT translate executor to screened executor; same as CompletableFuture.completeAsync
-        CompletableFutureUtils.completeExceptionallyAsync(cf, supplier, cffuUnscreenedExecutor(executor));
+        CompletableFutureUtils.completeExceptionallyAsync(cf, supplier, cffuUnscreened(executor));
         return this;
     }
 
diff --git a/cffu-core/src/main/java/io/foldright/cffu/CffuFactory.java b/cffu-core/src/main/java/io/foldright/cffu/CffuFactory.java
index 471e6d42..317e405f 100644
--- a/cffu-core/src/main/java/io/foldright/cffu/CffuFactory.java
+++ b/cffu-core/src/main/java/io/foldright/cffu/CffuFactory.java
@@ -18,8 +18,8 @@
 import java.util.concurrent.TimeUnit;
 import java.util.function.Supplier;
 
-import static io.foldright.cffu.CffuFactoryBuilder.cffuScreenedExecutor;
-import static io.foldright.cffu.CffuFactoryBuilder.cffuUnscreenedExecutor;
+import static io.foldright.cffu.CffuFactoryBuilder.cffuScreened;
+import static io.foldright.cffu.CffuFactoryBuilder.cffuUnscreened;
 import static java.util.Objects.requireNonNull;
 
 
@@ -134,7 +134,7 @@ public <T> Cffu<T> supplyAsync(Supplier<T> supplier) {
      */
     @CheckReturnValue(explanation = "should use the returned Cffu; otherwise, prefer method `runAsync`")
     public <T> Cffu<T> supplyAsync(Supplier<T> supplier, Executor executor) {
-        return create(CompletableFuture.supplyAsync(supplier, cffuScreenedExecutor(executor)));
+        return create(CompletableFuture.supplyAsync(supplier, cffuScreened(executor)));
     }
 
     /**
@@ -155,7 +155,7 @@ public Cffu<Void> runAsync(Runnable action) {
      * @param executor the executor to use for asynchronous execution
      */
     public Cffu<Void> runAsync(Runnable action, Executor executor) {
-        return create(CompletableFuture.runAsync(action, cffuScreenedExecutor(executor)));
+        return create(CompletableFuture.runAsync(action, cffuScreened(executor)));
     }
 
     // endregion
@@ -185,7 +185,7 @@ public final <T> Cffu<List<T>> mSupplyFailFastAsync(Supplier<? extends T>... sup
      */
     @SafeVarargs
     public final <T> Cffu<List<T>> mSupplyFailFastAsync(Executor executor, Supplier<? extends T>... suppliers) {
-        return create(CompletableFutureUtils.mSupplyFailFastAsync(cffuScreenedExecutor(executor), suppliers));
+        return create(CompletableFutureUtils.mSupplyFailFastAsync(cffuScreened(executor), suppliers));
     }
 
     /**
@@ -209,7 +209,7 @@ public final <T> Cffu<List<T>> mSupplyAllSuccessAsync(
     @SafeVarargs
     public final <T> Cffu<List<T>> mSupplyAllSuccessAsync(
             Executor executor, @Nullable T valueIfFailed, Supplier<? extends T>... suppliers) {
-        return create(CompletableFutureUtils.mSupplyAllSuccessAsync(cffuScreenedExecutor(executor), valueIfFailed, suppliers));
+        return create(CompletableFutureUtils.mSupplyAllSuccessAsync(cffuScreened(executor), valueIfFailed, suppliers));
     }
 
     /**
@@ -236,7 +236,8 @@ public final <T> Cffu<List<T>> mSupplyMostSuccessAsync(
     public final <T> Cffu<List<T>> mSupplyMostSuccessAsync(
             Executor executor, @Nullable T valueIfNotSuccess, long timeout, TimeUnit unit,
             Supplier<? extends T>... suppliers) {
-        return create(CompletableFutureUtils.mSupplyMostSuccessAsync(cffuScreenedExecutor(executor), valueIfNotSuccess, timeout, unit, suppliers));
+        return create(CompletableFutureUtils.mSupplyMostSuccessAsync(
+                cffuScreened(executor), valueIfNotSuccess, timeout, unit, suppliers));
     }
 
     /**
@@ -258,7 +259,7 @@ public final <T> Cffu<List<T>> mSupplyAsync(Supplier<? extends T>... suppliers)
     @SafeVarargs
     public final <T> Cffu<List<T>> mSupplyAsync(
             Executor executor, Supplier<? extends T>... suppliers) {
-        return create(CompletableFutureUtils.mSupplyAsync(cffuScreenedExecutor(executor), suppliers));
+        return create(CompletableFutureUtils.mSupplyAsync(cffuScreened(executor), suppliers));
     }
 
     /**
@@ -279,7 +280,7 @@ public final <T> Cffu<T> mSupplyAnySuccessAsync(Supplier<? extends T>... supplie
      */
     @SafeVarargs
     public final <T> Cffu<T> mSupplyAnySuccessAsync(Executor executor, Supplier<? extends T>... suppliers) {
-        return create(CompletableFutureUtils.mSupplyAnySuccessAsync(cffuScreenedExecutor(executor), suppliers));
+        return create(CompletableFutureUtils.mSupplyAnySuccessAsync(cffuScreened(executor), suppliers));
     }
 
     /**
@@ -300,7 +301,7 @@ public final <T> Cffu<T> mSupplyAnyAsync(Supplier<? extends T>... suppliers) {
      */
     @SafeVarargs
     public final <T> Cffu<T> mSupplyAnyAsync(Executor executor, Supplier<? extends T>... suppliers) {
-        return create(CompletableFutureUtils.mSupplyAnyAsync(cffuScreenedExecutor(executor), suppliers));
+        return create(CompletableFutureUtils.mSupplyAnyAsync(cffuScreened(executor), suppliers));
     }
 
     /**
@@ -319,7 +320,7 @@ public Cffu<Void> mRunFailFastAsync(Runnable... actions) {
      * See the {@link #allFailFastOf allFailFastOf} documentation for the rules of result computation.
      */
     public Cffu<Void> mRunFailFastAsync(Executor executor, Runnable... actions) {
-        return create(CompletableFutureUtils.mRunFailFastAsync(cffuScreenedExecutor(executor), actions));
+        return create(CompletableFutureUtils.mRunFailFastAsync(cffuScreened(executor), actions));
     }
 
     /**
@@ -337,7 +338,7 @@ public Cffu<Void> mRunAsync(Runnable... actions) {
      * See the {@link #allOf allOf} documentation for the rules of result computation.
      */
     public Cffu<Void> mRunAsync(Executor executor, Runnable... actions) {
-        return create(CompletableFutureUtils.mRunAsync(cffuScreenedExecutor(executor), actions));
+        return create(CompletableFutureUtils.mRunAsync(cffuScreened(executor), actions));
     }
 
     /**
@@ -356,7 +357,7 @@ public Cffu<Void> mRunAnySuccessAsync(Runnable... actions) {
      * See the {@link #anySuccessOf anySuccessOf} documentation for the rules of result computation.
      */
     public Cffu<Void> mRunAnySuccessAsync(Executor executor, Runnable... actions) {
-        return create(CompletableFutureUtils.mRunAnySuccessAsync(cffuScreenedExecutor(executor), actions));
+        return create(CompletableFutureUtils.mRunAnySuccessAsync(cffuScreened(executor), actions));
     }
 
     /**
@@ -374,7 +375,7 @@ public Cffu<Void> mRunAnyAsync(Runnable... actions) {
      * See the {@link #anyOf anyOf} documentation for the rules of result computation.
      */
     public Cffu<Void> mRunAnyAsync(Executor executor, Runnable... actions) {
-        return create(CompletableFutureUtils.mRunAnyAsync(cffuScreenedExecutor(executor), actions));
+        return create(CompletableFutureUtils.mRunAnyAsync(cffuScreened(executor), actions));
     }
 
     // endregion
@@ -395,7 +396,7 @@ public <T1, T2> Cffu<Tuple2<T1, T2>> mSupplyTupleFailFastAsync(
      */
     public <T1, T2> Cffu<Tuple2<T1, T2>> mSupplyTupleFailFastAsync(
             Executor executor, Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2) {
-        return create(CompletableFutureUtils.mSupplyTupleFailFastAsync(cffuScreenedExecutor(executor), supplier1, supplier2));
+        return create(CompletableFutureUtils.mSupplyTupleFailFastAsync(cffuScreened(executor), supplier1, supplier2));
     }
 
     /**
@@ -412,7 +413,7 @@ public <T1, T2, T3> Cffu<Tuple3<T1, T2, T3>> mSupplyTupleFailFastAsync(
     public <T1, T2, T3> Cffu<Tuple3<T1, T2, T3>> mSupplyTupleFailFastAsync(
             Executor executor, Supplier<? extends T1> supplier1,
             Supplier<? extends T2> supplier2, Supplier<? extends T3> supplier3) {
-        return create(CompletableFutureUtils.mSupplyTupleFailFastAsync(cffuScreenedExecutor(executor), supplier1, supplier2, supplier3));
+        return create(CompletableFutureUtils.mSupplyTupleFailFastAsync(cffuScreened(executor), supplier1, supplier2, supplier3));
     }
 
     /**
@@ -430,7 +431,8 @@ public <T1, T2, T3, T4> Cffu<Tuple4<T1, T2, T3, T4>> mSupplyTupleFailFastAsync(
     public <T1, T2, T3, T4> Cffu<Tuple4<T1, T2, T3, T4>> mSupplyTupleFailFastAsync(
             Executor executor, Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2,
             Supplier<? extends T3> supplier3, Supplier<? extends T4> supplier4) {
-        return create(CompletableFutureUtils.mSupplyTupleFailFastAsync(cffuScreenedExecutor(executor), supplier1, supplier2, supplier3, supplier4));
+        return create(CompletableFutureUtils.mSupplyTupleFailFastAsync(
+                cffuScreened(executor), supplier1, supplier2, supplier3, supplier4));
     }
 
     /**
@@ -449,7 +451,7 @@ public <T1, T2, T3, T4, T5> Cffu<Tuple5<T1, T2, T3, T4, T5>> mSupplyTupleFailFas
             Executor executor, Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2,
             Supplier<? extends T3> supplier3, Supplier<? extends T4> supplier4, Supplier<? extends T5> supplier5) {
         return create(CompletableFutureUtils.mSupplyTupleFailFastAsync(
-                cffuScreenedExecutor(executor), supplier1, supplier2, supplier3, supplier4, supplier5));
+                cffuScreened(executor), supplier1, supplier2, supplier3, supplier4, supplier5));
     }
 
     /**
@@ -471,7 +473,7 @@ public <T1, T2> Cffu<Tuple2<T1, T2>> mSupplyAllSuccessTupleAsync(
      */
     public <T1, T2> Cffu<Tuple2<T1, T2>> mSupplyAllSuccessTupleAsync(
             Executor executor, Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2) {
-        return create(CompletableFutureUtils.mSupplyAllSuccessTupleAsync(cffuScreenedExecutor(executor), supplier1, supplier2));
+        return create(CompletableFutureUtils.mSupplyAllSuccessTupleAsync(cffuScreened(executor), supplier1, supplier2));
     }
 
     /**
@@ -494,7 +496,7 @@ public <T1, T2, T3> Cffu<Tuple3<T1, T2, T3>> mSupplyAllSuccessTupleAsync(
     public <T1, T2, T3> Cffu<Tuple3<T1, T2, T3>> mSupplyAllSuccessTupleAsync(
             Executor executor, Supplier<? extends T1> supplier1,
             Supplier<? extends T2> supplier2, Supplier<? extends T3> supplier3) {
-        return create(CompletableFutureUtils.mSupplyAllSuccessTupleAsync(cffuScreenedExecutor(executor), supplier1, supplier2, supplier3));
+        return create(CompletableFutureUtils.mSupplyAllSuccessTupleAsync(cffuScreened(executor), supplier1, supplier2, supplier3));
     }
 
     /**
@@ -518,7 +520,8 @@ public <T1, T2, T3, T4> Cffu<Tuple4<T1, T2, T3, T4>> mSupplyAllSuccessTupleAsync
     public <T1, T2, T3, T4> Cffu<Tuple4<T1, T2, T3, T4>> mSupplyAllSuccessTupleAsync(
             Executor executor, Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2,
             Supplier<? extends T3> supplier3, Supplier<? extends T4> supplier4) {
-        return create(CompletableFutureUtils.mSupplyAllSuccessTupleAsync(cffuScreenedExecutor(executor), supplier1, supplier2, supplier3, supplier4));
+        return create(CompletableFutureUtils.mSupplyAllSuccessTupleAsync(
+                cffuScreened(executor), supplier1, supplier2, supplier3, supplier4));
     }
 
     /**
@@ -543,7 +546,7 @@ public <T1, T2, T3, T4, T5> Cffu<Tuple5<T1, T2, T3, T4, T5>> mSupplyAllSuccessTu
             Executor executor, Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2,
             Supplier<? extends T3> supplier3, Supplier<? extends T4> supplier4, Supplier<? extends T5> supplier5) {
         return create(CompletableFutureUtils.mSupplyAllSuccessTupleAsync(
-                cffuScreenedExecutor(executor), supplier1, supplier2, supplier3, supplier4, supplier5));
+                cffuScreened(executor), supplier1, supplier2, supplier3, supplier4, supplier5));
     }
 
     /**
@@ -567,7 +570,8 @@ public <T1, T2> Cffu<Tuple2<T1, T2>> mSupplyMostSuccessTupleAsync(
     public <T1, T2> Cffu<Tuple2<T1, T2>> mSupplyMostSuccessTupleAsync(
             Executor executor, long timeout, TimeUnit unit,
             Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2) {
-        return create(CompletableFutureUtils.mSupplyMostSuccessTupleAsync(cffuScreenedExecutor(executor), timeout, unit, supplier1, supplier2));
+        return create(CompletableFutureUtils.mSupplyMostSuccessTupleAsync(
+                cffuScreened(executor), timeout, unit, supplier1, supplier2));
     }
 
     /**
@@ -593,7 +597,7 @@ public <T1, T2, T3> Cffu<Tuple3<T1, T2, T3>> mSupplyMostSuccessTupleAsync(
             Executor executor, long timeout, TimeUnit unit,
             Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2, Supplier<? extends T3> supplier3) {
         return create(CompletableFutureUtils.mSupplyMostSuccessTupleAsync(
-                cffuScreenedExecutor(executor), timeout, unit, supplier1, supplier2, supplier3));
+                cffuScreened(executor), timeout, unit, supplier1, supplier2, supplier3));
     }
 
     /**
@@ -619,7 +623,7 @@ public <T1, T2, T3, T4> Cffu<Tuple4<T1, T2, T3, T4>> mSupplyMostSuccessTupleAsyn
             Executor executor, long timeout, TimeUnit unit, Supplier<? extends T1> supplier1,
             Supplier<? extends T2> supplier2, Supplier<? extends T3> supplier3, Supplier<? extends T4> supplier4) {
         return create(CompletableFutureUtils.mSupplyMostSuccessTupleAsync(
-                cffuScreenedExecutor(executor), timeout, unit, supplier1, supplier2, supplier3, supplier4));
+                cffuScreened(executor), timeout, unit, supplier1, supplier2, supplier3, supplier4));
     }
 
     /**
@@ -647,7 +651,7 @@ public <T1, T2, T3, T4, T5> Cffu<Tuple5<T1, T2, T3, T4, T5>> mSupplyMostSuccessT
             Supplier<? extends T2> supplier2, Supplier<? extends T3> supplier3,
             Supplier<? extends T4> supplier4, Supplier<? extends T5> supplier5) {
         return create(CompletableFutureUtils.mSupplyMostSuccessTupleAsync(
-                cffuScreenedExecutor(executor), timeout, unit, supplier1, supplier2, supplier3, supplier4, supplier5));
+                cffuScreened(executor), timeout, unit, supplier1, supplier2, supplier3, supplier4, supplier5));
     }
 
     /**
@@ -663,7 +667,7 @@ public <T1, T2> Cffu<Tuple2<T1, T2>> mSupplyTupleAsync(
      */
     public <T1, T2> Cffu<Tuple2<T1, T2>> mSupplyTupleAsync(
             Executor executor, Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2) {
-        return create(CompletableFutureUtils.mSupplyTupleAsync(cffuScreenedExecutor(executor), supplier1, supplier2));
+        return create(CompletableFutureUtils.mSupplyTupleAsync(cffuScreened(executor), supplier1, supplier2));
     }
 
     /**
@@ -680,7 +684,7 @@ public <T1, T2, T3> Cffu<Tuple3<T1, T2, T3>> mSupplyTupleAsync(
     public <T1, T2, T3> Cffu<Tuple3<T1, T2, T3>> mSupplyTupleAsync(
             Executor executor, Supplier<? extends T1> supplier1,
             Supplier<? extends T2> supplier2, Supplier<? extends T3> supplier3) {
-        return create(CompletableFutureUtils.mSupplyTupleAsync(cffuScreenedExecutor(executor), supplier1, supplier2, supplier3));
+        return create(CompletableFutureUtils.mSupplyTupleAsync(cffuScreened(executor), supplier1, supplier2, supplier3));
     }
 
     /**
@@ -698,7 +702,8 @@ public <T1, T2, T3, T4> Cffu<Tuple4<T1, T2, T3, T4>> mSupplyTupleAsync(
     public <T1, T2, T3, T4> Cffu<Tuple4<T1, T2, T3, T4>> mSupplyTupleAsync(
             Executor executor, Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2,
             Supplier<? extends T3> supplier3, Supplier<? extends T4> supplier4) {
-        return create(CompletableFutureUtils.mSupplyTupleAsync(cffuScreenedExecutor(executor), supplier1, supplier2, supplier3, supplier4));
+        return create(CompletableFutureUtils.mSupplyTupleAsync(
+                cffuScreened(executor), supplier1, supplier2, supplier3, supplier4));
     }
 
     /**
@@ -717,7 +722,7 @@ public <T1, T2, T3, T4, T5> Cffu<Tuple5<T1, T2, T3, T4, T5>> mSupplyTupleAsync(
             Executor executor, Supplier<? extends T1> supplier1, Supplier<? extends T2> supplier2,
             Supplier<? extends T3> supplier3, Supplier<? extends T4> supplier4, Supplier<? extends T5> supplier5) {
         return create(CompletableFutureUtils.mSupplyTupleAsync(
-                cffuScreenedExecutor(executor), supplier1, supplier2, supplier3, supplier4, supplier5));
+                cffuScreened(executor), supplier1, supplier2, supplier3, supplier4, supplier5));
     }
 
     // endregion
@@ -795,7 +800,7 @@ public final <T> Cffu<List<T>> allSuccessResultsOf(
     public final <T> Cffu<List<T>> mostSuccessResultsOf(
             @Nullable T valueIfNotSuccess, long timeout, TimeUnit unit, CompletionStage<? extends T>... cfs) {
         return create(CompletableFutureUtils.mostSuccessResultsOf(
-                cffuScreenedExecutor(cffuExecutor), valueIfNotSuccess, timeout, unit, cfs));
+                cffuScreened(cffuExecutor), valueIfNotSuccess, timeout, unit, cfs));
     }
 
     /**
@@ -1018,7 +1023,7 @@ public <T1, T2, T3, T4, T5> Cffu<Tuple5<T1, T2, T3, T4, T5>> allSuccessTupleOf(
     @Contract(pure = true)
     public <T1, T2> Cffu<Tuple2<T1, T2>> mostSuccessTupleOf(
             long timeout, TimeUnit unit, CompletionStage<? extends T1> cf1, CompletionStage<? extends T2> cf2) {
-        return create(CompletableFutureUtils.mostSuccessTupleOf(cffuScreenedExecutor(cffuExecutor), timeout, unit, cf1, cf2));
+        return create(CompletableFutureUtils.mostSuccessTupleOf(cffuScreened(cffuExecutor), timeout, unit, cf1, cf2));
     }
 
     /**
@@ -1032,7 +1037,8 @@ public <T1, T2> Cffu<Tuple2<T1, T2>> mostSuccessTupleOf(
     public <T1, T2, T3> Cffu<Tuple3<T1, T2, T3>> mostSuccessTupleOf(
             long timeout, TimeUnit unit,
             CompletionStage<? extends T1> cf1, CompletionStage<? extends T2> cf2, CompletionStage<? extends T3> cf3) {
-        return create(CompletableFutureUtils.mostSuccessTupleOf(cffuScreenedExecutor(cffuExecutor), timeout, unit, cf1, cf2, cf3));
+        return create(CompletableFutureUtils.mostSuccessTupleOf(
+                cffuScreened(cffuExecutor), timeout, unit, cf1, cf2, cf3));
     }
 
     /**
@@ -1047,7 +1053,8 @@ public <T1, T2, T3, T4> Cffu<Tuple4<T1, T2, T3, T4>> mostSuccessTupleOf(
             long timeout, TimeUnit unit,
             CompletionStage<? extends T1> cf1, CompletionStage<? extends T2> cf2,
             CompletionStage<? extends T3> cf3, CompletionStage<? extends T4> cf4) {
-        return create(CompletableFutureUtils.mostSuccessTupleOf(cffuScreenedExecutor(cffuExecutor), timeout, unit, cf1, cf2, cf3, cf4));
+        return create(CompletableFutureUtils.mostSuccessTupleOf(
+                cffuScreened(cffuExecutor), timeout, unit, cf1, cf2, cf3, cf4));
     }
 
     /**
@@ -1062,7 +1069,8 @@ public <T1, T2, T3, T4, T5> Cffu<Tuple5<T1, T2, T3, T4, T5>> mostSuccessTupleOf(
             long timeout, TimeUnit unit,
             CompletionStage<? extends T1> cf1, CompletionStage<? extends T2> cf2, CompletionStage<? extends T3> cf3,
             CompletionStage<? extends T4> cf4, CompletionStage<? extends T5> cf5) {
-        return create(CompletableFutureUtils.mostSuccessTupleOf(cffuScreenedExecutor(cffuExecutor), timeout, unit, cf1, cf2, cf3, cf4, cf5));
+        return create(CompletableFutureUtils.mostSuccessTupleOf(
+                cffuScreened(cffuExecutor), timeout, unit, cf1, cf2, cf3, cf4, cf5));
     }
 
     /**
@@ -1244,7 +1252,7 @@ public Executor delayedExecutor(long delay, TimeUnit unit) {
     @Contract(pure = true)
     public Executor delayedExecutor(long delay, TimeUnit unit, Executor executor) {
         // NOTE: do NOT translate executor to screened executor; same as CompletableFuture.delayedExecutor
-        return CompletableFutureUtils.delayedExecutor(delay, unit, cffuUnscreenedExecutor(executor));
+        return CompletableFutureUtils.delayedExecutor(delay, unit, cffuUnscreened(executor));
     }
 
     // endregion
diff --git a/cffu-core/src/main/java/io/foldright/cffu/CffuFactoryBuilder.java b/cffu-core/src/main/java/io/foldright/cffu/CffuFactoryBuilder.java
index 338803fb..7c9183ab 100644
--- a/cffu-core/src/main/java/io/foldright/cffu/CffuFactoryBuilder.java
+++ b/cffu-core/src/main/java/io/foldright/cffu/CffuFactoryBuilder.java
@@ -3,7 +3,6 @@
 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import io.foldright.cffu.spi.ExecutorWrapperProvider;
 import org.jetbrains.annotations.Contract;
-import org.jetbrains.annotations.VisibleForTesting;
 
 import javax.annotation.concurrent.ThreadSafe;
 import java.util.List;
@@ -34,7 +33,7 @@ public final class CffuFactoryBuilder {
     private volatile boolean forbidObtrudeMethods = false;
 
     CffuFactoryBuilder(Executor defaultExecutor) {
-        this.cffuExecutor = makeCffuExecutorWrapper(defaultExecutor);
+        this.cffuExecutor = new CffuExecutorWrapper(defaultExecutor);
     }
 
     // endregion
@@ -85,27 +84,24 @@ private static CffuFactory _poisonObject() {
     @Contract(pure = true)
     static CffuFactory withDefaultExecutor(CffuFactory fac, Executor defaultExecutor) {
         if (fac.cffuExecutor.original == defaultExecutor) return fac;
-        else return new CffuFactory(makeCffuExecutorWrapper(defaultExecutor), fac.forbidObtrudeMethods());
-    }
-
-    private static CffuExecutorWrapper makeCffuExecutorWrapper(final Executor defaultExecutor) {
-        assert !(defaultExecutor instanceof CffuExecutorWrapper) : "input defaultExecutor should never be a CffuExecutorWrapper";
-        assert !(defaultExecutor instanceof CffuMadeExecutor) : "input defaultExecutor should never be a CffuMadeExecutor";
-
-        requireNonNull(defaultExecutor, "defaultExecutor is null");
-        return new CffuExecutorWrapper(defaultExecutor);
+        else return new CffuFactory(new CffuExecutorWrapper(defaultExecutor), fac.forbidObtrudeMethods());
     }
 
     static class CffuExecutorWrapper implements Executor {
         final Executor original;
-        @VisibleForTesting
         final Executor unscreened;
-        @VisibleForTesting
         final Executor screened;
 
+        @SuppressFBWarnings("CT_CONSTRUCTOR_THROW")
         private CffuExecutorWrapper(Executor defaultExecutor) {
+            requireNonNull(defaultExecutor, "defaultExecutor is null");
+            if (defaultExecutor instanceof CffuExecutorWrapper)
+                throw new IllegalArgumentException("input defaultExecutor should never be a CffuExecutorWrapper");
+            if (defaultExecutor instanceof CffuMadeExecutor)
+                throw new IllegalArgumentException("input defaultExecutor should never be a CffuMadeExecutor");
+
             original = defaultExecutor;
-            unscreened = wrapExecutorWithProviders(defaultExecutor, defaultExecutor);;
+            unscreened = wrapExecutorWithProviders(defaultExecutor, defaultExecutor);
 
             Executor screenedExecutor = LLCF.screenExecutor(defaultExecutor);
             if (screenedExecutor == defaultExecutor) screened = unscreened;
@@ -114,7 +110,7 @@ private CffuExecutorWrapper(Executor defaultExecutor) {
 
         /**
          * This method is never called directly. Instead, use the related {@link #screened}/{@link #unscreened} executor
-         * from method {@link #cffuScreenedExecutor(Executor)}/{@link #cffuUnscreenedExecutor(Executor)} respectively.
+         * from method {@link #cffuScreened(Executor)}/{@link #cffuUnscreened(Executor)} respectively.
          */
         @Override
         public void execute(Runnable command) {
@@ -127,21 +123,24 @@ public String toString() {
         }
     }
 
-    static Executor cffuScreenedExecutor(Executor executor) {
-        assert !(executor instanceof CffuMadeExecutor) : "input executor should never be a CffuMadeExecutor";
-
+    @SuppressWarnings("ConstantValue")
+    static Executor cffuScreened(Executor executor) {
+        if (executor == null) return null;
         if (executor instanceof CffuExecutorWrapper) return ((CffuExecutorWrapper) executor).screened;
         return wrapExecutorWithProviders(LLCF.screenExecutor(executor), executor);
     }
 
-    static Executor cffuUnscreenedExecutor(Executor executor) {
-        assert !(executor instanceof CffuMadeExecutor) : "input executor should never be a CffuMadeExecutor";
-
+    @SuppressWarnings("ConstantValue")
+    static Executor cffuUnscreened(Executor executor) {
+        if (executor == null) return null;
         if (executor instanceof CffuExecutorWrapper) return ((CffuExecutorWrapper) executor).unscreened;
         return wrapExecutorWithProviders(executor, executor);
     }
 
     private static CffuMadeExecutor wrapExecutorWithProviders(Executor executor, Executor original) {
+        if (executor instanceof CffuMadeExecutor)
+            throw new IllegalArgumentException("input executor should never be a CffuMadeExecutor");
+
         for (ExecutorWrapperProvider provider : EXECUTOR_WRAPPER_PROVIDERS) {
             Supplier<String> msg = () -> provider + "(class: " + provider.getClass().getName() + ") return null";
             executor = requireNonNull(provider.wrap(executor), msg);
@@ -157,9 +156,9 @@ private static List<ExecutorWrapperProvider> loadExecutorWrapperProviders() {
     }
 
     /**
-     * A class for avoiding re-wrapping.
+     * A little class to prevent duplicate wrapping of executors.
      */
-    private static class CffuMadeExecutor implements Executor {
+    private static final class CffuMadeExecutor implements Executor {
         final Executor wrappedExecutor;
         final Executor original;
 
diff --git a/cffu-core/src/test/java/io/foldright/cffu/CffuFactoryBuilderTest.kt b/cffu-core/src/test/java/io/foldright/cffu/CffuFactoryBuilderTest.kt
new file mode 100644
index 00000000..15e946be
--- /dev/null
+++ b/cffu-core/src/test/java/io/foldright/cffu/CffuFactoryBuilderTest.kt
@@ -0,0 +1,33 @@
+package io.foldright.cffu
+
+import io.foldright.test_utils.testCffuFac
+import io.kotest.assertions.throwables.shouldThrowExactly
+import io.kotest.core.spec.style.FunSpec
+import io.kotest.matchers.nulls.shouldBeNull
+import io.kotest.matchers.shouldBe
+import io.kotest.matchers.string.shouldContain
+import io.kotest.matchers.string.shouldStartWith
+
+@Suppress("NULLABILITY_MISMATCH_BASED_ON_JAVA_ANNOTATIONS")
+class CffuFactoryBuilderTest : FunSpec({
+    test("cffu (un)screened") {
+        CffuFactoryBuilder.cffuScreened(null).shouldBeNull()
+        CffuFactoryBuilder.cffuUnscreened(null).shouldBeNull()
+
+        shouldThrowExactly<IllegalArgumentException> {
+            CffuFactoryBuilder.cffuScreened(testCffuFac.cffuExecutor.screened)
+        }.message shouldBe "input executor should never be a CffuMadeExecutor"
+        shouldThrowExactly<IllegalArgumentException> {
+            CffuFactoryBuilder.cffuUnscreened(testCffuFac.cffuExecutor.screened)
+        }.message shouldBe "input executor should never be a CffuMadeExecutor"
+
+        testCffuFac.cffuExecutor.screened.toString().shouldStartWith("CffuMadeExecutor, wrappedExecutor: ")
+            .shouldContain(" original: ")
+        testCffuFac.cffuExecutor.unscreened.toString().shouldStartWith("CffuMadeExecutor, wrappedExecutor: ")
+            .shouldContain(" original: ")
+
+        shouldThrowExactly<UnsupportedOperationException> {
+            testCffuFac.cffuExecutor.execute(null)
+        }
+    }
+})
diff --git a/cffu-core/src/test/java/io/foldright/cffu/CffuFactoryTest.java b/cffu-core/src/test/java/io/foldright/cffu/CffuFactoryTest.java
index d4a963ad..4bbe956b 100644
--- a/cffu-core/src/test/java/io/foldright/cffu/CffuFactoryTest.java
+++ b/cffu-core/src/test/java/io/foldright/cffu/CffuFactoryTest.java
@@ -877,6 +877,7 @@ void test_cffuListToArray() {
     void test_getter() {
         assertSame(testExecutor, testCffuFac.defaultExecutor());
         assertThat(testCffuFac.cffuExecutor.toString()).startsWith("CffuExecutorWrapper, original: ");
+        assertSame(testCffuFac.cffuExecutor.screened, testCffuFac.cffuExecutor.unscreened);
 
         assertSame(testExecutor, testCffuFac.defaultExecutor());
         assertFalse(testCffuFac.forbidObtrudeMethods());
@@ -889,9 +890,16 @@ void test_getter() {
         assertSame(dummyExecutor, fac2.defaultExecutor());
         assertEquals(testCffuFac.forbidObtrudeMethods(), fac2.forbidObtrudeMethods());
 
-        final CffuFactory fac3 = testCffuFac.withDefaultExecutor(fac2.defaultExecutor());
-        assertSame(fac2.defaultExecutor(), fac3.defaultExecutor());
-        assertEquals(fac2.forbidObtrudeMethods(), fac3.forbidObtrudeMethods());
+        assertSame(fac2, fac2.withDefaultExecutor(fac2.defaultExecutor()));
+
+        final CffuFactory facCp = CffuFactory.builder(commonPool()).forbidObtrudeMethods(false).build();
+        if (CffuTestHelper.useCommonPool()) assertSame(facCp.cffuExecutor.screened, facCp.cffuExecutor.unscreened);
+        else assertNotSame(facCp.cffuExecutor.screened, facCp.cffuExecutor.unscreened);
+
+        assertEquals("input defaultExecutor should never be a CffuExecutorWrapper", assertThrowsExactly(
+                IllegalArgumentException.class, () -> fac2.withDefaultExecutor(fac2.cffuExecutor)).getMessage());
+        assertEquals("input defaultExecutor should never be a CffuMadeExecutor", assertThrowsExactly(
+                IllegalArgumentException.class, () -> fac2.withDefaultExecutor(fac2.cffuExecutor.screened)).getMessage());
     }
 
     @Test
diff --git a/cffu-core/src/test/java/io/foldright/cffu/CffuTestHelper.kt b/cffu-core/src/test/java/io/foldright/cffu/CffuTestHelper.kt
index 2640c099..c57645c7 100644
--- a/cffu-core/src/test/java/io/foldright/cffu/CffuTestHelper.kt
+++ b/cffu-core/src/test/java/io/foldright/cffu/CffuTestHelper.kt
@@ -21,9 +21,10 @@ fun CffuFactory.getUnscreenedExecutor(): Executor = cffuExecutor.unscreened
 
 class FooCs<T>(cf: CompletableFuture<T>) : CompletionStage<T> by cf
 
+fun useCommonPool() = ForkJoinPool.getCommonPoolParallelism() > 1
+
 fun assertIsCfDefaultExecutor(executor: Executor) {
-    val useCommonPool = ForkJoinPool.getCommonPoolParallelism() > 1
-    if (useCommonPool) {
+    if (useCommonPool()) {
         executor shouldBeSameInstanceAs ForkJoinPool.commonPool()
     } else {
         executor.javaClass.name shouldEndWith "\$ThreadPerTaskExecutor"