diff --git a/akka-javasdk/src/main/scala/akka/javasdk/impl/consumer/ConsumerEffectImpl.scala b/akka-javasdk/src/main/scala/akka/javasdk/impl/consumer/ConsumerEffectImpl.scala
index 9f424fa5e..0b5da20fb 100644
--- a/akka-javasdk/src/main/scala/akka/javasdk/impl/consumer/ConsumerEffectImpl.scala
+++ b/akka-javasdk/src/main/scala/akka/javasdk/impl/consumer/ConsumerEffectImpl.scala
@@ -20,7 +20,7 @@ import akka.javasdk.consumer.Consumer
 private[impl] object ConsumerEffectImpl {
   sealed abstract class PrimaryEffect extends Consumer.Effect {}
 
-  final case class ReplyEffect[T](msg: T, metadata: Option[Metadata]) extends PrimaryEffect {
+  final case class ProduceEffect[T](msg: T, metadata: Option[Metadata]) extends PrimaryEffect {
     def isEmpty: Boolean = false
   }
 
@@ -33,10 +33,10 @@ private[impl] object ConsumerEffectImpl {
   }
 
   object Builder extends Consumer.Effect.Builder {
-    def produce[S](message: S): Consumer.Effect = ReplyEffect(message, None)
+    def produce[S](message: S): Consumer.Effect = ProduceEffect(message, None)
 
     def produce[S](message: S, metadata: Metadata): Consumer.Effect =
-      ReplyEffect(message, Some(metadata))
+      ProduceEffect(message, Some(metadata))
 
     def asyncProduce[S](futureMessage: CompletionStage[S]): Consumer.Effect =
       asyncProduce(futureMessage, Metadata.EMPTY)
@@ -48,7 +48,7 @@ private[impl] object ConsumerEffectImpl {
       IgnoreEffect
 
     override def done(): Consumer.Effect =
-      ReplyEffect(Done, None)
+      ProduceEffect(Done, None)
 
     override def asyncDone(futureMessage: CompletionStage[Done]): Consumer.Effect =
       AsyncEffect(futureMessage.asScala.map(done => Builder.produce(done))(ExecutionContext.parasitic))
diff --git a/akka-javasdk/src/main/scala/akka/javasdk/impl/consumer/ConsumerImpl.scala b/akka-javasdk/src/main/scala/akka/javasdk/impl/consumer/ConsumerImpl.scala
index 620a01d44..cd0a99032 100644
--- a/akka-javasdk/src/main/scala/akka/javasdk/impl/consumer/ConsumerImpl.scala
+++ b/akka-javasdk/src/main/scala/akka/javasdk/impl/consumer/ConsumerImpl.scala
@@ -23,7 +23,7 @@ import akka.javasdk.impl.ErrorHandling
 import akka.javasdk.impl.MetadataImpl
 import akka.javasdk.impl.consumer.ConsumerEffectImpl.AsyncEffect
 import akka.javasdk.impl.consumer.ConsumerEffectImpl.IgnoreEffect
-import akka.javasdk.impl.consumer.ConsumerEffectImpl.ReplyEffect
+import akka.javasdk.impl.consumer.ConsumerEffectImpl.ProduceEffect
 import akka.javasdk.impl.serialization.JsonSerializer
 import akka.javasdk.impl.telemetry.SpanTracingImpl
 import akka.javasdk.impl.telemetry.Telemetry
@@ -33,7 +33,6 @@ import akka.runtime.sdk.spi.BytesPayload
 import akka.runtime.sdk.spi.SpiConsumer
 import akka.runtime.sdk.spi.SpiConsumer.Effect
 import akka.runtime.sdk.spi.SpiConsumer.Message
-import akka.runtime.sdk.spi.SpiMetadata
 import akka.runtime.sdk.spi.SpiMetadataEntry
 import akka.runtime.sdk.spi.TimerClient
 import io.opentelemetry.api.trace.Span
@@ -101,13 +100,11 @@ private[impl] final class ConsumerImpl[C <: Consumer](
 
   private def toSpiEffect(message: Message, effect: Consumer.Effect): Future[Effect] = {
     effect match {
-      case ReplyEffect(msg, metadata) =>
+      case ProduceEffect(msg, metadata) =>
         Future.successful(
-          new Effect(
-            ignore = false,
-            reply = Some(serializer.toBytes(msg)),
-            metadata = MetadataImpl.toSpi(metadata),
-            error = None))
+          new SpiConsumer.ProduceEffect(
+            payload = Some(serializer.toBytes(msg)),
+            metadata = MetadataImpl.toSpi(metadata)))
       case AsyncEffect(futureEffect) =>
         futureEffect
           .flatMap { effect => toSpiEffect(message, effect) }
@@ -115,7 +112,7 @@ private[impl] final class ConsumerImpl[C <: Consumer](
             handleUnexpectedException(message, ex)
           }
       case IgnoreEffect =>
-        Future.successful(new Effect(ignore = true, reply = None, metadata = SpiMetadata.empty, error = None))
+        Future.successful(SpiConsumer.IgnoreEffect)
       case unknown =>
         throw new IllegalArgumentException(s"Unknown TimedAction.Effect type ${unknown.getClass}")
     }
@@ -134,11 +131,7 @@ private[impl] final class ConsumerImpl[C <: Consumer](
   }
 
   private def protocolFailure(correlationId: String): Effect = {
-    new Effect(
-      ignore = false,
-      reply = None,
-      metadata = SpiMetadata.empty,
-      error = Some(new SpiConsumer.Error(s"Unexpected error [$correlationId]")))
+    new SpiConsumer.ErrorEffect(error = new SpiConsumer.Error(s"Unexpected error [$correlationId]"))
   }
 
 }
diff --git a/akka-javasdk/src/main/scala/akka/javasdk/impl/timedaction/TimedActionImpl.scala b/akka-javasdk/src/main/scala/akka/javasdk/impl/timedaction/TimedActionImpl.scala
index 40bb92e19..a12624d4f 100644
--- a/akka-javasdk/src/main/scala/akka/javasdk/impl/timedaction/TimedActionImpl.scala
+++ b/akka-javasdk/src/main/scala/akka/javasdk/impl/timedaction/TimedActionImpl.scala
@@ -125,7 +125,7 @@ private[impl] final class TimedActionImpl[TA <: TimedAction](
   private def toSpiEffect(command: Command, effect: TimedAction.Effect): Future[Effect] = {
     effect match {
       case ReplyEffect(_) => //FIXME remove meta, not used in the reply
-        Future.successful(new Effect(None))
+        Future.successful(SpiTimedAction.SuccessEffect)
       case AsyncEffect(futureEffect) =>
         futureEffect
           .flatMap { effect => toSpiEffect(command, effect) }
@@ -133,7 +133,7 @@ private[impl] final class TimedActionImpl[TA <: TimedAction](
             handleUnexpectedException(command, ex)
           }
       case ErrorEffect(description) =>
-        Future.successful(new Effect(Some(new SpiTimedAction.Error(description))))
+        Future.successful(new SpiTimedAction.ErrorEffect(new SpiTimedAction.Error(description)))
       case unknown =>
         throw new IllegalArgumentException(s"Unknown TimedAction.Effect type ${unknown.getClass}")
     }
@@ -152,7 +152,7 @@ private[impl] final class TimedActionImpl[TA <: TimedAction](
   }
 
   private def protocolFailure(correlationId: String): Effect = {
-    new Effect(Some(new SpiTimedAction.Error(s"Unexpected error [$correlationId]")))
+    new SpiTimedAction.ErrorEffect(new SpiTimedAction.Error(s"Unexpected error [$correlationId]"))
   }
 
 }
diff --git a/akka-javasdk/src/test/scala/akka/javasdk/impl/timedaction/TimedActionImplSpec.scala b/akka-javasdk/src/test/scala/akka/javasdk/impl/timedaction/TimedActionImplSpec.scala
index fb66e0583..6c9daa327 100644
--- a/akka-javasdk/src/test/scala/akka/javasdk/impl/timedaction/TimedActionImplSpec.scala
+++ b/akka-javasdk/src/test/scala/akka/javasdk/impl/timedaction/TimedActionImplSpec.scala
@@ -87,7 +87,7 @@ class TimedActionImplSpec
             new SpiTimedAction.Command("MyMethod", Some(new BytesPayload(ByteString.empty, "")), SpiMetadata.empty))
           .futureValue
 
-      reply.error shouldBe empty
+      reply shouldBe an[SpiTimedAction.SuccessEffect.type]
     }
 
     "turn thrown command handler exceptions into failure responses" in {
@@ -104,9 +104,10 @@ class TimedActionImplSpec
                   Some(new BytesPayload(ByteString.empty, "")),
                   SpiMetadata.empty))
               .futureValue
+              .asInstanceOf[SpiTimedAction.ErrorEffect]
           }
 
-      reply.error.value.description should startWith("Unexpected error")
+      reply.error.description should startWith("Unexpected error")
     }
 
   }