diff --git a/core/amber/src/main/scala/edu/uci/ics/amber/engine/architecture/scheduling/ScheduleGenerator.scala b/core/amber/src/main/scala/edu/uci/ics/amber/engine/architecture/scheduling/ScheduleGenerator.scala
index 217d77aa14e..8da5d420142 100644
--- a/core/amber/src/main/scala/edu/uci/ics/amber/engine/architecture/scheduling/ScheduleGenerator.scala
+++ b/core/amber/src/main/scala/edu/uci/ics/amber/engine/architecture/scheduling/ScheduleGenerator.scala
@@ -1,17 +1,15 @@
 package edu.uci.ics.amber.engine.architecture.scheduling
 
+import edu.uci.ics.amber.core.executor.OpExecInitInfo
 import edu.uci.ics.amber.core.storage.result.{OpResultStorage, ResultStorage}
 import edu.uci.ics.amber.core.tuple.Schema
-import edu.uci.ics.amber.core.workflow.{PhysicalOp, PhysicalPlan, WorkflowContext}
+import edu.uci.ics.amber.core.workflow.{PhysicalOp, PhysicalPlan, SchemaPropagationFunc, WorkflowContext}
 import edu.uci.ics.amber.engine.architecture.scheduling.ScheduleGenerator.replaceVertex
-import edu.uci.ics.amber.engine.architecture.scheduling.resourcePolicies.{
-  DefaultResourceAllocator,
-  ExecutionClusterInfo
-}
+import edu.uci.ics.amber.engine.architecture.scheduling.resourcePolicies.{DefaultResourceAllocator, ExecutionClusterInfo}
 import edu.uci.ics.amber.operator.sink.managed.ProgressiveSinkOpDesc
-import edu.uci.ics.amber.operator.source.cache.CacheSourceOpDesc
+import edu.uci.ics.amber.operator.source.cache.CacheSourceOpExec
 import edu.uci.ics.amber.virtualidentity.{OperatorIdentity, PhysicalOpIdentity, WorkflowIdentity}
-import edu.uci.ics.amber.workflow.PhysicalLink
+import edu.uci.ics.amber.workflow.{OutputPort, PhysicalLink}
 import org.jgrapht.graph.DirectedAcyclicGraph
 import org.jgrapht.traverse.TopologicalOrderIterator
 
@@ -169,7 +167,7 @@ abstract class ScheduleGenerator(
 
     // create cache reader and link
     val matReaderPhysicalOp: PhysicalOp =
-      createMatReader(matWriterPhysicalOp.id.logicalOpId, physicalLink, workflowContext.workflowId)
+      createMatReader(matWriterPhysicalOp.id.logicalOpId, physicalLink)
     val readerToDestLink =
       PhysicalLink(
         matReaderPhysicalOp.id,
@@ -186,20 +184,31 @@ abstract class ScheduleGenerator(
 
   private def createMatReader(
       matWriterLogicalOpId: OperatorIdentity,
-      physicalLink: PhysicalLink,
-      workflowIdentity: WorkflowIdentity
+      physicalLink: PhysicalLink
   ): PhysicalOp = {
-    val matReader = new CacheSourceOpDesc(
-      matWriterLogicalOpId,
-      ResultStorage.getOpResultStorage(workflowIdentity)
-    )
-    matReader.setContext(workflowContext)
-    matReader.setOperatorId(s"cacheSource_${getMatIdFromPhysicalLink(physicalLink)}")
-
-    matReader
-      .getPhysicalOp(
+    println("Creating mat reader!!!")
+    PhysicalOp
+      .sourcePhysicalOp(
         workflowContext.workflowId,
-        workflowContext.executionId
+        workflowContext.executionId,
+        OperatorIdentity(s"cacheSource_${getMatIdFromPhysicalLink(physicalLink)}"),
+        OpExecInitInfo((_, _) =>
+          new CacheSourceOpExec(
+            ResultStorage.getOpResultStorage(workflowContext.workflowId).get(matWriterLogicalOpId)
+          )
+        )
+      )
+      .withInputPorts(List.empty)
+      .withOutputPorts(List(OutputPort()))
+      .withPropagateSchema(
+        SchemaPropagationFunc(_ =>
+          Map(
+            OutputPort().id -> ResultStorage
+              .getOpResultStorage(workflowContext.workflowId)
+              .getSchema(matWriterLogicalOpId)
+              .get
+          )
+        )
       )
       .propagateSchema()