diff --git a/demo/src/main/java/com/google/android/fhir/demo/HomeFragment.kt b/demo/src/main/java/com/google/android/fhir/demo/HomeFragment.kt
index f7b2a649c9..402a5e19ea 100644
--- a/demo/src/main/java/com/google/android/fhir/demo/HomeFragment.kt
+++ b/demo/src/main/java/com/google/android/fhir/demo/HomeFragment.kt
@@ -45,7 +45,7 @@ class HomeFragment : Fragment(R.layout.fragment_home) {
       findNavController().navigate(HomeFragmentDirections.actionHomeFragmentToPatientList())
     }
     requireView().findViewById<CardView>(R.id.item_sync).setOnClickListener {
-      findNavController().navigate(HomeFragmentDirections.actionHomeFragmentToManualSyncFragment())
+      findNavController().navigate(HomeFragmentDirections.actionHomeFragmentToSyncFragment())
     }
     requireView().findViewById<CardView>(R.id.item_periodic_sync).setOnClickListener {
       findNavController()
diff --git a/demo/src/main/java/com/google/android/fhir/demo/PeriodicSyncFragment.kt b/demo/src/main/java/com/google/android/fhir/demo/PeriodicSyncFragment.kt
index 3019cf136d..6e8e56de82 100644
--- a/demo/src/main/java/com/google/android/fhir/demo/PeriodicSyncFragment.kt
+++ b/demo/src/main/java/com/google/android/fhir/demo/PeriodicSyncFragment.kt
@@ -75,41 +75,48 @@ class PeriodicSyncFragment : Fragment() {
   private fun periodicSyncJobStatus(periodicSyncJobStatus: PeriodicSyncJobStatus) {
     // Handle last sync job status and update UI
     periodicSyncJobStatus.lastSyncJobStatus?.let { lastStatus ->
-      val lastSyncStatusValue = when (lastStatus) {
-        is LastSyncJobStatus.Succeeded -> getString(R.string.last_sync_status, LastSyncJobStatus.Succeeded::class.java.simpleName)
-        is LastSyncJobStatus.Failed -> getString(R.string.last_sync_status, LastSyncJobStatus.Failed::class.java.simpleName)
-        else -> null
-      }
+      val lastSyncStatusValue =
+        when (lastStatus) {
+          is LastSyncJobStatus.Succeeded ->
+            getString(R.string.last_sync_status, LastSyncJobStatus.Succeeded::class.java.simpleName)
+          is LastSyncJobStatus.Failed ->
+            getString(R.string.last_sync_status, LastSyncJobStatus.Failed::class.java.simpleName)
+          else -> null
+        }
 
       lastSyncStatusValue?.let { statusText ->
         requireView().findViewById<TextView>(R.id.last_sync_status).text = statusText
-        requireView().findViewById<TextView>(R.id.last_sync_time).text = getString(
-          R.string.last_sync_timestamp,
-          syncFragmentViewModel.formatSyncTimestamp(lastStatus.timestamp)
-        )
+        requireView().findViewById<TextView>(R.id.last_sync_time).text =
+          getString(
+            R.string.last_sync_timestamp,
+            syncFragmentViewModel.formatSyncTimestamp(lastStatus.timestamp),
+          )
       }
     }
 
     // Set current sync status
     val currentSyncStatusTextView = requireView().findViewById<TextView>(R.id.current_sync_status)
-    currentSyncStatusTextView.text = getString(
-      R.string.current_status,
-      periodicSyncJobStatus.currentSyncJobStatus::class.java.simpleName
-    )
+    currentSyncStatusTextView.text =
+      getString(
+        R.string.current_status,
+        periodicSyncJobStatus.currentSyncJobStatus::class.java.simpleName,
+      )
 
     // Update progress indicator visibility based on current sync status
     val syncIndicator = requireView().findViewById<ProgressBar>(R.id.sync_indicator)
-    syncIndicator.visibility = if (periodicSyncJobStatus.currentSyncJobStatus is CurrentSyncJobStatus.Running) {
-      View.VISIBLE
-    } else {
-      View.GONE
-    }
+    syncIndicator.visibility =
+      if (periodicSyncJobStatus.currentSyncJobStatus is CurrentSyncJobStatus.Running) {
+        View.VISIBLE
+      } else {
+        View.GONE
+      }
 
     // Control the visibility of the current sync status text view
-    currentSyncStatusTextView.visibility = when (periodicSyncJobStatus.currentSyncJobStatus) {
-      is CurrentSyncJobStatus.Failed, is CurrentSyncJobStatus.Succeeded -> View.GONE
-      else -> View.VISIBLE
-    }
+    currentSyncStatusTextView.visibility =
+      when (periodicSyncJobStatus.currentSyncJobStatus) {
+        is CurrentSyncJobStatus.Failed,
+        is CurrentSyncJobStatus.Succeeded, -> View.GONE
+        else -> View.VISIBLE
+      }
   }
-
 }
diff --git a/demo/src/main/res/navigation/reference_nav_graph.xml b/demo/src/main/res/navigation/reference_nav_graph.xml
index 08a6e8d8e2..e4e4d22e63 100644
--- a/demo/src/main/res/navigation/reference_nav_graph.xml
+++ b/demo/src/main/res/navigation/reference_nav_graph.xml
@@ -22,8 +22,8 @@
             app:destination="@id/patient_list"
         />
     <action
-            android:id="@+id/action_home_fragment_to_manual_sync_fragment"
-            app:destination="@id/manualSyncFragment"
+            android:id="@+id/action_home_fragment_to_sync_fragment"
+            app:destination="@id/syncFragment"
         />
     <action
             android:id="@+id/action_home_fragment_to_periodic_sync_fragment"
@@ -89,7 +89,7 @@
     </fragment>
 
   <fragment
-        android:id="@+id/manualSyncFragment"
+        android:id="@+id/syncFragment"
         android:name="com.google.android.fhir.demo.SyncFragment"
         android:label="fragment_manual_sync"
         tools:layout="@layout/sync"
@@ -101,5 +101,4 @@
         android:label="fragment_periodic_sync"
         tools:layout="@layout/periodic_sync"
     />
-
 </navigation>
diff --git a/engine/src/androidTest/java/com/google/android/fhir/db/impl/DatabaseImplTest.kt b/engine/src/androidTest/java/com/google/android/fhir/db/impl/DatabaseImplTest.kt
index 123c474cc5..ec85746b4a 100644
--- a/engine/src/androidTest/java/com/google/android/fhir/db/impl/DatabaseImplTest.kt
+++ b/engine/src/androidTest/java/com/google/android/fhir/db/impl/DatabaseImplTest.kt
@@ -559,8 +559,8 @@ class DatabaseImplTest {
     // Delete the patient created in setup as we only want to upload the patient in this test
     database.deleteUpdates(listOf(TEST_PATIENT_1))
     services.fhirEngine
-      .syncUpload(AllChangesSquashedBundlePut) {
-        it
+      .syncUpload(AllChangesSquashedBundlePut) { lcs, _ ->
+        lcs
           .first { it.resourceId == "remote-patient-3" }
           .let {
             flowOf(
diff --git a/engine/src/main/java/com/google/android/fhir/FhirEngine.kt b/engine/src/main/java/com/google/android/fhir/FhirEngine.kt
index bb4dfb0241..d03645c530 100644
--- a/engine/src/main/java/com/google/android/fhir/FhirEngine.kt
+++ b/engine/src/main/java/com/google/android/fhir/FhirEngine.kt
@@ -16,6 +16,7 @@
 
 package com.google.android.fhir
 
+import com.google.android.fhir.db.LocalChangeResourceReference
 import com.google.android.fhir.db.ResourceNotFoundException
 import com.google.android.fhir.search.Search
 import com.google.android.fhir.sync.ConflictResolver
@@ -121,7 +122,10 @@ interface FhirEngine {
   @Deprecated("To be deprecated.")
   suspend fun syncUpload(
     uploadStrategy: UploadStrategy,
-    upload: (suspend (List<LocalChange>) -> Flow<UploadRequestResult>),
+    upload:
+      (suspend (List<LocalChange>, List<LocalChangeResourceReference>) -> Flow<
+          UploadRequestResult,
+        >),
   ): Flow<SyncUploadProgress>
 
   /**
diff --git a/engine/src/main/java/com/google/android/fhir/db/Database.kt b/engine/src/main/java/com/google/android/fhir/db/Database.kt
index 7f321ae712..24e5c300f0 100644
--- a/engine/src/main/java/com/google/android/fhir/db/Database.kt
+++ b/engine/src/main/java/com/google/android/fhir/db/Database.kt
@@ -215,7 +215,7 @@ internal data class ResourceWithUUID<R>(
   val resource: R,
 )
 
-internal data class LocalChangeResourceReference(
+data class LocalChangeResourceReference(
   val localChangeId: Long,
   val resourceReferenceValue: String,
   val resourceReferencePath: String?,
diff --git a/engine/src/main/java/com/google/android/fhir/impl/FhirEngineImpl.kt b/engine/src/main/java/com/google/android/fhir/impl/FhirEngineImpl.kt
index fe5331bd73..faef0c90ac 100644
--- a/engine/src/main/java/com/google/android/fhir/impl/FhirEngineImpl.kt
+++ b/engine/src/main/java/com/google/android/fhir/impl/FhirEngineImpl.kt
@@ -22,6 +22,7 @@ import com.google.android.fhir.FhirEngineProvider
 import com.google.android.fhir.LocalChange
 import com.google.android.fhir.SearchResult
 import com.google.android.fhir.db.Database
+import com.google.android.fhir.db.LocalChangeResourceReference
 import com.google.android.fhir.logicalId
 import com.google.android.fhir.search.Search
 import com.google.android.fhir.search.count
@@ -124,7 +125,10 @@ internal class FhirEngineImpl(private val database: Database, private val contex
 
   override suspend fun syncUpload(
     uploadStrategy: UploadStrategy,
-    upload: (suspend (List<LocalChange>) -> Flow<UploadRequestResult>),
+    upload:
+      (suspend (List<LocalChange>, List<LocalChangeResourceReference>) -> Flow<
+          UploadRequestResult,
+        >),
   ): Flow<SyncUploadProgress> = flow {
     val resourceConsolidator =
       ResourceConsolidatorFactory.byHttpVerb(uploadStrategy.requestGeneratorMode, database)
@@ -140,8 +144,10 @@ internal class FhirEngineImpl(private val database: Database, private val contex
 
     while (localChangeFetcher.hasNext()) {
       val localChanges = localChangeFetcher.next()
+      val localChangeReferences =
+        database.getLocalChangeResourceReferences(localChanges.flatMap { it.token.ids })
       val uploadRequestResult =
-        upload(localChanges)
+        upload(localChanges, localChangeReferences)
           .onEach { result ->
             resourceConsolidator.consolidate(result)
             val newProgress =
diff --git a/engine/src/main/java/com/google/android/fhir/sync/FhirSyncWorker.kt b/engine/src/main/java/com/google/android/fhir/sync/FhirSyncWorker.kt
index afb43458be..45320ce810 100644
--- a/engine/src/main/java/com/google/android/fhir/sync/FhirSyncWorker.kt
+++ b/engine/src/main/java/com/google/android/fhir/sync/FhirSyncWorker.kt
@@ -94,11 +94,7 @@ abstract class FhirSyncWorker(appContext: Context, workerParams: WorkerParameter
           uploader =
             Uploader(
               dataSource = dataSource,
-              patchGenerator =
-                PatchGeneratorFactory.byMode(
-                  getUploadStrategy().patchGeneratorMode,
-                  FhirEngineProvider.getFhirDatabase(applicationContext),
-                ),
+              patchGenerator = PatchGeneratorFactory.byMode(getUploadStrategy().patchGeneratorMode),
               requestGenerator =
                 UploadRequestGeneratorFactory.byMode(getUploadStrategy().requestGeneratorMode),
             ),
diff --git a/engine/src/main/java/com/google/android/fhir/sync/upload/Uploader.kt b/engine/src/main/java/com/google/android/fhir/sync/upload/Uploader.kt
index 83e8f0d345..4802efd75c 100644
--- a/engine/src/main/java/com/google/android/fhir/sync/upload/Uploader.kt
+++ b/engine/src/main/java/com/google/android/fhir/sync/upload/Uploader.kt
@@ -17,6 +17,7 @@
 package com.google.android.fhir.sync.upload
 
 import com.google.android.fhir.LocalChange
+import com.google.android.fhir.db.LocalChangeResourceReference
 import com.google.android.fhir.sync.DataSource
 import com.google.android.fhir.sync.ResourceSyncException
 import com.google.android.fhir.sync.upload.patch.PatchGenerator
@@ -49,9 +50,12 @@ internal class Uploader(
   private val patchGenerator: PatchGenerator,
   private val requestGenerator: UploadRequestGenerator,
 ) {
-  suspend fun upload(localChanges: List<LocalChange>) =
+  suspend fun upload(
+    localChanges: List<LocalChange>,
+    localChangesReferences: List<LocalChangeResourceReference>,
+  ) =
     localChanges
-      .let { patchGenerator.generate(it) }
+      .let { patchGenerator.generate(it, localChangesReferences) }
       .let { requestGenerator.generateUploadRequests(it) }
       .asFlow()
       .transformWhile {
diff --git a/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PatchGenerator.kt b/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PatchGenerator.kt
index 6dfda6e191..fc13dedb3b 100644
--- a/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PatchGenerator.kt
+++ b/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PatchGenerator.kt
@@ -17,7 +17,7 @@
 package com.google.android.fhir.sync.upload.patch
 
 import com.google.android.fhir.LocalChange
-import com.google.android.fhir.db.Database
+import com.google.android.fhir.db.LocalChangeResourceReference
 
 /**
  * Generates [Patch]es from [LocalChange]s and output [List<[StronglyConnectedPatchMappings]>] to
@@ -35,17 +35,17 @@ internal interface PatchGenerator {
    * NOTE: different implementations may have requirements on the size of [localChanges] and output
    * certain numbers of [Patch]es.
    */
-  suspend fun generate(localChanges: List<LocalChange>): List<StronglyConnectedPatchMappings>
+  suspend fun generate(
+    localChanges: List<LocalChange>,
+    localChangesReferences: List<LocalChangeResourceReference>,
+  ): List<StronglyConnectedPatchMappings>
 }
 
 internal object PatchGeneratorFactory {
-  fun byMode(
-    mode: PatchGeneratorMode,
-    database: Database,
-  ): PatchGenerator =
+  fun byMode(mode: PatchGeneratorMode): PatchGenerator =
     when (mode) {
       is PatchGeneratorMode.PerChange -> PerChangePatchGenerator
-      is PatchGeneratorMode.PerResource -> PerResourcePatchGenerator.with(database)
+      is PatchGeneratorMode.PerResource -> PerResourcePatchGenerator
     }
 }
 
diff --git a/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PatchOrdering.kt b/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PatchOrdering.kt
index d0bfb5f364..e0d0dab3bb 100644
--- a/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PatchOrdering.kt
+++ b/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PatchOrdering.kt
@@ -17,7 +17,6 @@
 package com.google.android.fhir.sync.upload.patch
 
 import androidx.annotation.VisibleForTesting
-import com.google.android.fhir.db.Database
 import com.google.android.fhir.db.LocalChangeResourceReference
 
 /** Represents a resource e.g. 'Patient/123' , 'Encounter/123'. */
@@ -68,27 +67,27 @@ internal object PatchOrdering {
     get() = "${generatedPatch.resourceType}/${generatedPatch.resourceId}"
 
   /**
-   * Order the [PatchMapping] so that if the resource A has outgoing references {B,C} (CREATE) and
-   * {D} (UPDATE), then B,C needs to go before the resource A so that referential integrity is
-   * retained. Order of D shouldn't matter for the purpose of referential integrity.
+   * Orders the list of [PatchMapping]s to maintain referential integrity.
    *
-   * @return A ordered list of the [StronglyConnectedPatchMappings] containing:
-   * - [StronglyConnectedPatchMappings] with single value for the [PatchMapping] based on the
-   *   references to other [PatchMapping] if the mappings are acyclic
-   * - [StronglyConnectedPatchMappings] with multiple values for [PatchMapping]s based on the
-   *   references to other [PatchMapping]s if the mappings are cyclic.
+   * This function ensures that if resource A has a CREATE reference to resources B and C, then B
+   * and C appear before A in the ordered list. UPDATE references are not considered as they do not
+   * impact referential integrity.
+   *
+   * The function uses Strongly Connected Components (SCC) to handle cyclic dependencies.
+   *
+   * @return A list of [StronglyConnectedPatchMappings]:
+   *     - Each [StronglyConnectedPatchMappings] object represents an SCC.
+   *     - If the graph of references is acyclic, each [StronglyConnectedPatchMappings] will contain
+   *       a single [PatchMapping].
+   *     - If the graph has cycles, a [StronglyConnectedPatchMappings] object will contain multiple
+   *       [PatchMapping]s involved in the cycle.
    */
-  suspend fun List<PatchMapping>.sccOrderByReferences(
-    database: Database,
+  fun List<PatchMapping>.sccOrderByReferences(
+    localChangeResourceReferences: List<LocalChangeResourceReference>,
   ): List<StronglyConnectedPatchMappings> {
     val resourceIdToPatchMapping = associateBy { patchMapping -> patchMapping.resourceTypeAndId }
-    /* Get LocalChangeResourceReferences for all the local changes. A single LocalChange may have
-    multiple LocalChangeResourceReference, one for each resource reference in the
-    LocalChange.payload.*/
-    val localChangeIdToResourceReferenceMap: Map<Long, List<LocalChangeResourceReference>> =
-      database
-        .getLocalChangeResourceReferences(flatMap { it.localChanges.flatMap { it.token.ids } })
-        .groupBy { it.localChangeId }
+    val localChangeIdToResourceReferenceMap =
+      localChangeResourceReferences.groupBy { it.localChangeId }
 
     val adjacencyList = createAdjacencyListForCreateReferences(localChangeIdToResourceReferenceMap)
 
diff --git a/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PerChangePatchGenerator.kt b/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PerChangePatchGenerator.kt
index c208e8c6ea..8be3b21dc6 100644
--- a/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PerChangePatchGenerator.kt
+++ b/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PerChangePatchGenerator.kt
@@ -17,6 +17,7 @@
 package com.google.android.fhir.sync.upload.patch
 
 import com.google.android.fhir.LocalChange
+import com.google.android.fhir.db.LocalChangeResourceReference
 
 /**
  * Generates a [Patch] for each [LocalChange].
@@ -27,6 +28,7 @@ import com.google.android.fhir.LocalChange
 internal object PerChangePatchGenerator : PatchGenerator {
   override suspend fun generate(
     localChanges: List<LocalChange>,
+    localChangesReferences: List<LocalChangeResourceReference>,
   ): List<StronglyConnectedPatchMappings> =
     localChanges
       .map {
diff --git a/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PerResourcePatchGenerator.kt b/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PerResourcePatchGenerator.kt
index c524b32302..5579da3237 100644
--- a/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PerResourcePatchGenerator.kt
+++ b/engine/src/main/java/com/google/android/fhir/sync/upload/patch/PerResourcePatchGenerator.kt
@@ -22,7 +22,7 @@ import com.github.fge.jackson.JsonLoader
 import com.github.fge.jsonpatch.JsonPatch
 import com.google.android.fhir.LocalChange
 import com.google.android.fhir.LocalChange.Type
-import com.google.android.fhir.db.Database
+import com.google.android.fhir.db.LocalChangeResourceReference
 import com.google.android.fhir.sync.upload.patch.PatchOrdering.sccOrderByReferences
 
 /**
@@ -32,13 +32,13 @@ import com.google.android.fhir.sync.upload.patch.PatchOrdering.sccOrderByReferen
  * maintain an audit trail, but instead, multiple changes made to the same FHIR resource on the
  * client can be recorded as a single change on the server.
  */
-internal class PerResourcePatchGenerator private constructor(val database: Database) :
-  PatchGenerator {
+internal object PerResourcePatchGenerator : PatchGenerator {
 
   override suspend fun generate(
     localChanges: List<LocalChange>,
+    localChangesReferences: List<LocalChangeResourceReference>,
   ): List<StronglyConnectedPatchMappings> {
-    return generateSquashedChangesMapping(localChanges).sccOrderByReferences(database)
+    return generateSquashedChangesMapping(localChanges).sccOrderByReferences(localChangesReferences)
   }
 
   @androidx.annotation.VisibleForTesting
@@ -147,20 +147,4 @@ internal class PerResourcePatchGenerator private constructor(val database: Datab
     mergedOperations.values.flatten().forEach(mergedNode::add)
     return objectMapper.writeValueAsString(mergedNode)
   }
-
-  companion object {
-
-    @Volatile private lateinit var _instance: PerResourcePatchGenerator
-
-    @Synchronized
-    fun with(database: Database): PerResourcePatchGenerator {
-      if (!::_instance.isInitialized) {
-        _instance = PerResourcePatchGenerator(database)
-      } else if (_instance.database != database) {
-        _instance = PerResourcePatchGenerator(database)
-      }
-
-      return _instance
-    }
-  }
 }
diff --git a/engine/src/main/java/com/google/android/fhir/testing/Utilities.kt b/engine/src/main/java/com/google/android/fhir/testing/Utilities.kt
index c99e17be73..0c5f80a1bf 100644
--- a/engine/src/main/java/com/google/android/fhir/testing/Utilities.kt
+++ b/engine/src/main/java/com/google/android/fhir/testing/Utilities.kt
@@ -24,6 +24,7 @@ import com.google.android.fhir.FhirEngine
 import com.google.android.fhir.LocalChange
 import com.google.android.fhir.LocalChangeToken
 import com.google.android.fhir.SearchResult
+import com.google.android.fhir.db.LocalChangeResourceReference
 import com.google.android.fhir.search.Search
 import com.google.android.fhir.sync.ConflictResolver
 import com.google.android.fhir.sync.DataSource
@@ -158,10 +159,11 @@ internal object TestFhirEngineImpl : FhirEngine {
 
   override suspend fun syncUpload(
     uploadStrategy: UploadStrategy,
-    upload: suspend (List<LocalChange>) -> Flow<UploadRequestResult>,
+    upload:
+      suspend (List<LocalChange>, List<LocalChangeResourceReference>) -> Flow<UploadRequestResult>,
   ): Flow<SyncUploadProgress> = flow {
     emit(SyncUploadProgress(1, 1))
-    upload(getLocalChanges(ResourceType.Patient, "123")).collect {
+    upload(getLocalChanges(ResourceType.Patient, "123"), emptyList()).collect {
       when (it) {
         is UploadRequestResult.Success -> emit(SyncUploadProgress(0, 1))
         is UploadRequestResult.Failure -> emit(SyncUploadProgress(1, 1, it.uploadError))
diff --git a/engine/src/test/java/com/google/android/fhir/impl/FhirEngineImplTest.kt b/engine/src/test/java/com/google/android/fhir/impl/FhirEngineImplTest.kt
index 48be1a491b..f767675ed1 100644
--- a/engine/src/test/java/com/google/android/fhir/impl/FhirEngineImplTest.kt
+++ b/engine/src/test/java/com/google/android/fhir/impl/FhirEngineImplTest.kt
@@ -323,13 +323,13 @@ class FhirEngineImplTest {
     val emittedProgress = mutableListOf<SyncUploadProgress>()
 
     fhirEngine
-      .syncUpload(UploadStrategy.AllChangesSquashedBundlePut) {
-        localChanges.addAll(it)
+      .syncUpload(UploadStrategy.AllChangesSquashedBundlePut) { lcs, _ ->
+        localChanges.addAll(lcs)
         flowOf(
           UploadRequestResult.Success(
             listOf(
               ResourceUploadResponseMapping(
-                it,
+                lcs,
                 TEST_PATIENT_1,
               ),
             ),
@@ -356,10 +356,10 @@ class FhirEngineImplTest {
     val emittedProgress = mutableListOf<SyncUploadProgress>()
     val uploadError = ResourceSyncException(ResourceType.Patient, FHIRException("Did not work"))
     fhirEngine
-      .syncUpload(UploadStrategy.AllChangesSquashedBundlePut) {
+      .syncUpload(UploadStrategy.AllChangesSquashedBundlePut) { lcs, _ ->
         flowOf(
           UploadRequestResult.Failure(
-            it,
+            lcs,
             uploadError,
           ),
         )
@@ -767,12 +767,12 @@ class FhirEngineImplTest {
   fun `test local changes are consumed when using POST upload strategy`() = runBlocking {
     assertThat(services.database.getLocalChangesCount()).isEqualTo(1)
     fhirEngine
-      .syncUpload(UploadStrategy.SingleResourcePost) {
+      .syncUpload(UploadStrategy.SingleResourcePost) { lcs, _ ->
         flowOf(
           UploadRequestResult.Success(
             listOf(
               ResourceUploadResponseMapping(
-                it,
+                lcs,
                 TEST_PATIENT_1,
               ),
             ),
diff --git a/engine/src/test/java/com/google/android/fhir/sync/FhirSynchronizerTest.kt b/engine/src/test/java/com/google/android/fhir/sync/FhirSynchronizerTest.kt
index 22c6fb6709..5967e05742 100644
--- a/engine/src/test/java/com/google/android/fhir/sync/FhirSynchronizerTest.kt
+++ b/engine/src/test/java/com/google/android/fhir/sync/FhirSynchronizerTest.kt
@@ -70,7 +70,7 @@ class FhirSynchronizerTest {
   fun `synchronize should return Success on successful download and upload`() =
     runTest(UnconfinedTestDispatcher()) {
       `when`(downloader.download()).thenReturn(flowOf(DownloadState.Success(listOf(), 10, 10)))
-      `when`(uploader.upload(any()))
+      `when`(uploader.upload(any(), any()))
         .thenReturn(
           flowOf(UploadRequestResult.Success(listOf())),
         )
@@ -97,7 +97,7 @@ class FhirSynchronizerTest {
     runTest(UnconfinedTestDispatcher()) {
       val error = ResourceSyncException(ResourceType.Patient, Exception("Download error"))
       `when`(downloader.download()).thenReturn(flowOf(DownloadState.Failure(error)))
-      `when`(uploader.upload(any()))
+      `when`(uploader.upload(any(), any()))
         .thenReturn(
           flowOf(UploadRequestResult.Success(listOf())),
         )
@@ -122,7 +122,7 @@ class FhirSynchronizerTest {
     runTest(UnconfinedTestDispatcher()) {
       `when`(downloader.download()).thenReturn(flowOf(DownloadState.Success(listOf(), 10, 10)))
       val error = ResourceSyncException(ResourceType.Patient, Exception("Upload error"))
-      `when`(uploader.upload(any()))
+      `when`(uploader.upload(any(), any()))
         .thenReturn(flowOf(UploadRequestResult.Failure(listOf(), error)))
 
       val emittedValues = mutableListOf<SyncJobStatus>()
@@ -148,7 +148,7 @@ class FhirSynchronizerTest {
   fun `synchronize multiple invocations should execute in order`() =
     runTest(UnconfinedTestDispatcher()) {
       `when`(downloader.download()).thenReturn(flowOf(DownloadState.Success(listOf(), 0, 0)))
-      `when`(uploader.upload(any()))
+      `when`(uploader.upload(any(), any()))
         .thenReturn(
           flowOf(
             UploadRequestResult.Success(
diff --git a/engine/src/test/java/com/google/android/fhir/sync/upload/UploaderTest.kt b/engine/src/test/java/com/google/android/fhir/sync/upload/UploaderTest.kt
index feffe91d7c..f71df803a1 100644
--- a/engine/src/test/java/com/google/android/fhir/sync/upload/UploaderTest.kt
+++ b/engine/src/test/java/com/google/android/fhir/sync/upload/UploaderTest.kt
@@ -65,9 +65,8 @@ class UploaderTest {
     MockitoAnnotations.openMocks(this)
     runTest { whenever(database.getLocalChangeResourceReferences(any())).thenReturn(emptyList()) }
 
-    perResourcePatchGenerator =
-      PatchGeneratorFactory.byMode(PatchGeneratorMode.PerResource, database)
-    perChangePatchGenerator = PatchGeneratorFactory.byMode(PatchGeneratorMode.PerChange, database)
+    perResourcePatchGenerator = PatchGeneratorFactory.byMode(PatchGeneratorMode.PerResource)
+    perChangePatchGenerator = PatchGeneratorFactory.byMode(PatchGeneratorMode.PerChange)
   }
 
   @Test
@@ -98,7 +97,7 @@ class UploaderTest {
             perResourcePatchGenerator,
             bundleUploadRequestGenerator,
           )
-          .upload(localChangesToTestSuccess)
+          .upload(localChangesToTestSuccess, emptyList())
           .toList()
 
       // With BundleUploadRequestGenerator, all patches will be squashed into 1 request (default
@@ -156,7 +155,7 @@ class UploaderTest {
             perChangePatchGenerator,
             bundleUploadRequestGenerator,
           )
-          .upload(localChangesToTestSuccess)
+          .upload(localChangesToTestSuccess, emptyList())
           .toList()
 
       // With BundleUploadRequestGenerator, all patches will be squashed into 1 request (default
@@ -196,7 +195,7 @@ class UploaderTest {
           perResourcePatchGenerator,
           bundleUploadRequestGenerator,
         )
-        .upload(localChangesToTestFail)
+        .upload(localChangesToTestFail, emptyList())
         .toList()
 
     assertThat(result).hasSize(1)
@@ -221,7 +220,7 @@ class UploaderTest {
           perResourcePatchGenerator,
           bundleUploadRequestGenerator,
         )
-        .upload(localChangesToTestFail)
+        .upload(localChangesToTestFail, emptyList())
         .toList()
 
     assertThat(result).hasSize(1)
@@ -236,7 +235,7 @@ class UploaderTest {
           perResourcePatchGenerator,
           bundleUploadRequestGenerator,
         )
-        .upload(localChangesToTestFail)
+        .upload(localChangesToTestFail, emptyList())
         .toList()
 
     assertThat(result).hasSize(1)
@@ -252,7 +251,7 @@ class UploaderTest {
             perResourcePatchGenerator,
             bundleUploadRequestGenerator,
           )
-          .upload(localChangesToTestFail)
+          .upload(localChangesToTestFail, emptyList())
           .toList()
 
       assertThat(result).hasSize(1)
@@ -267,7 +266,7 @@ class UploaderTest {
           perResourcePatchGenerator,
           bundleUploadRequestGenerator,
         )
-        .upload(localChangesToTestFail)
+        .upload(localChangesToTestFail, emptyList())
         .toList()
 
     assertThat(result).hasSize(1)
@@ -299,7 +298,7 @@ class UploaderTest {
             perResourcePatchGenerator,
             urlUploadRequestGenerator,
           )
-          .upload(localChangesToTestSuccess)
+          .upload(localChangesToTestSuccess, emptyList())
           .toList()
 
       // With UrlUploadRequestGenerator, patch-per-resource is mapped to one url request. So total
@@ -359,7 +358,7 @@ class UploaderTest {
             perChangePatchGenerator,
             urlUploadRequestGenerator,
           )
-          .upload(localChangesToTestSuccess)
+          .upload(localChangesToTestSuccess, emptyList())
           .toList()
 
       // With UrlUploadRequestGenerator, patch-per-resource is mapped to one url request. So total
@@ -405,7 +404,7 @@ class UploaderTest {
           perResourcePatchGenerator,
           urlUploadRequestGenerator,
         )
-        .upload(localChangesToTestFail)
+        .upload(localChangesToTestFail, emptyList())
         .toList()
 
     assertThat(result).hasSize(1)
@@ -430,7 +429,7 @@ class UploaderTest {
           perResourcePatchGenerator,
           urlUploadRequestGenerator,
         )
-        .upload(localChangesToTestFail)
+        .upload(localChangesToTestFail, emptyList())
         .toList()
 
     assertThat(result).hasSize(1)
@@ -445,7 +444,7 @@ class UploaderTest {
           perResourcePatchGenerator,
           urlUploadRequestGenerator,
         )
-        .upload(localChangesToTestFail)
+        .upload(localChangesToTestFail, emptyList())
         .toList()
 
     assertThat(result).hasSize(1)
@@ -460,7 +459,7 @@ class UploaderTest {
           perResourcePatchGenerator,
           urlUploadRequestGenerator,
         )
-        .upload(localChangesToTestFail)
+        .upload(localChangesToTestFail, emptyList())
         .toList()
 
     assertThat(result).hasSize(1)
@@ -504,7 +503,7 @@ class UploaderTest {
             perResourcePatchGenerator,
             bundleUploadRequestGeneratorWithUnityBundleSize,
           )
-          .upload(localChangesToTestSuccess)
+          .upload(localChangesToTestSuccess, emptyList())
           .toList()
 
       // With BundleUploadRequestGenerator and bundleSize=1, each patch is mapped to a bundle
diff --git a/engine/src/test/java/com/google/android/fhir/sync/upload/patch/PatchOrderingTest.kt b/engine/src/test/java/com/google/android/fhir/sync/upload/patch/PatchOrderingTest.kt
index f6bcae7883..2ccadfd464 100644
--- a/engine/src/test/java/com/google/android/fhir/sync/upload/patch/PatchOrderingTest.kt
+++ b/engine/src/test/java/com/google/android/fhir/sync/upload/patch/PatchOrderingTest.kt
@@ -18,7 +18,6 @@ package com.google.android.fhir.sync.upload.patch
 
 import com.google.android.fhir.LocalChange
 import com.google.android.fhir.LocalChangeToken
-import com.google.android.fhir.db.Database
 import com.google.android.fhir.db.LocalChangeResourceReference
 import com.google.android.fhir.db.impl.dao.diff
 import com.google.android.fhir.logicalId
@@ -36,26 +35,14 @@ import org.hl7.fhir.r4.model.Patient
 import org.hl7.fhir.r4.model.Reference
 import org.hl7.fhir.r4.model.RelatedPerson
 import org.hl7.fhir.r4.model.Resource
-import org.junit.Before
 import org.junit.Test
 import org.junit.runner.RunWith
-import org.mockito.Mock
-import org.mockito.MockitoAnnotations
-import org.mockito.kotlin.any
-import org.mockito.kotlin.whenever
 import org.robolectric.RobolectricTestRunner
 
 @RunWith(RobolectricTestRunner::class)
 class PatchOrderingTest {
 
-  @Mock private lateinit var database: Database
-  private lateinit var patchGenerator: PerResourcePatchGenerator
-
-  @Before
-  fun setUp() {
-    MockitoAnnotations.openMocks(this)
-    patchGenerator = PerResourcePatchGenerator.with(database)
-  }
+  private val patchGenerator = PerResourcePatchGenerator
 
   @Test
   fun `createReferenceAdjacencyList with local changes for only new resources should only have edges to inserted resources`() =
@@ -77,8 +64,6 @@ class PatchOrderingTest {
       helper.createEncounter("encounter-3", 11, "Patient/patient-3")
       helper.createObservation("observation-3", 12, "Patient/patient-3", "Encounter/encounter-3")
       group = helper.updateGroup(group, 13, "Patient/patient-3")
-      whenever(database.getLocalChangeResourceReferences(any()))
-        .thenReturn(helper.localChangeResourceReferences)
 
       val result =
         patchGenerator
@@ -175,10 +160,7 @@ class PatchOrderingTest {
     helper.createEncounter("encounter-3", 12, "Patient/patient-3")
     helper.createPatient("patient-3", 13)
 
-    whenever(database.getLocalChangeResourceReferences(any()))
-      .thenReturn(helper.localChangeResourceReferences)
-
-    val result = patchGenerator.generate(helper.localChanges)
+    val result = patchGenerator.generate(helper.localChanges, helper.localChangeResourceReferences)
 
     // This order is based on the current implementation of the topological sort in [PatchOrdering],
     // it's entirely possible to generate different order here which is acceptable/correct, should
@@ -221,10 +203,8 @@ class PatchOrderingTest {
       helper.createEncounter("encounter-2", 8, "Patient/patient-3")
       helper.createPatient("patient-3", 9)
 
-      whenever(database.getLocalChangeResourceReferences(any()))
-        .thenReturn(helper.localChangeResourceReferences)
-
-      val result = patchGenerator.generate(helper.localChanges)
+      val result =
+        patchGenerator.generate(helper.localChanges, helper.localChangeResourceReferences)
 
       assertThat(
           result.map { it.patchMappings.map { it.generatedPatch.resourceId } },
diff --git a/engine/src/test/java/com/google/android/fhir/sync/upload/patch/PerResourcePatchGeneratorTest.kt b/engine/src/test/java/com/google/android/fhir/sync/upload/patch/PerResourcePatchGeneratorTest.kt
index 38811c581d..11fb7b0979 100644
--- a/engine/src/test/java/com/google/android/fhir/sync/upload/patch/PerResourcePatchGeneratorTest.kt
+++ b/engine/src/test/java/com/google/android/fhir/sync/upload/patch/PerResourcePatchGeneratorTest.kt
@@ -20,7 +20,6 @@ import ca.uhn.fhir.context.FhirContext
 import ca.uhn.fhir.context.FhirVersionEnum
 import com.google.android.fhir.LocalChange
 import com.google.android.fhir.LocalChangeToken
-import com.google.android.fhir.db.Database
 import com.google.android.fhir.db.impl.dao.diff
 import com.google.android.fhir.db.impl.entities.LocalChangeEntity
 import com.google.android.fhir.logicalId
@@ -42,27 +41,14 @@ import org.hl7.fhir.r4.model.Patient
 import org.hl7.fhir.r4.model.Resource
 import org.hl7.fhir.r4.model.ResourceType
 import org.json.JSONArray
-import org.junit.Before
 import org.junit.Test
 import org.junit.runner.RunWith
-import org.mockito.Mock
-import org.mockito.MockitoAnnotations
-import org.mockito.kotlin.any
-import org.mockito.kotlin.whenever
 import org.robolectric.RobolectricTestRunner
 
 @RunWith(RobolectricTestRunner::class)
 class PerResourcePatchGeneratorTest {
 
-  @Mock private lateinit var database: Database
-  private lateinit var patchGenerator: PerResourcePatchGenerator
-
-  @Before
-  fun setUp() {
-    MockitoAnnotations.openMocks(this)
-    runTest { whenever(database.getLocalChangeResourceReferences(any())).thenReturn(emptyList()) }
-    patchGenerator = PerResourcePatchGenerator.with(database)
-  }
+  private val patchGenerator = PerResourcePatchGenerator
 
   @Test
   fun `should generate a single insert patch if the resource is inserted`() = runTest {
@@ -70,7 +56,9 @@ class PerResourcePatchGeneratorTest {
     val insertionLocalChange = createInsertLocalChange(patient)
 
     val patches =
-      patchGenerator.generate(listOf(insertionLocalChange)).map { it.patchMappings.single() }
+      patchGenerator.generate(listOf(insertionLocalChange), emptyList()).map {
+        it.patchMappings.single()
+      }
 
     with(patches.single()) {
       with(generatedPatch) {
@@ -102,7 +90,9 @@ class PerResourcePatchGeneratorTest {
     val updatePatch = readJsonArrayFromFile("/update_patch_1.json")
 
     val patches =
-      patchGenerator.generate(listOf(updateLocalChange1)).map { it.patchMappings.single() }
+      patchGenerator.generate(listOf(updateLocalChange1), emptyList()).map {
+        it.patchMappings.single()
+      }
 
     with(patches.single()) {
       with(generatedPatch) {
@@ -132,7 +122,9 @@ class PerResourcePatchGeneratorTest {
     val deleteLocalChange = createDeleteLocalChange(remotePatient, 3L)
 
     val patches =
-      patchGenerator.generate(listOf(deleteLocalChange)).map { it.patchMappings.single() }
+      patchGenerator.generate(listOf(deleteLocalChange), emptyList()).map {
+        it.patchMappings.single()
+      }
 
     with(patches.single()) {
       with(generatedPatch) {
@@ -159,7 +151,7 @@ class PerResourcePatchGeneratorTest {
     val patientString = jsonParser.encodeResourceToString(updatedPatient)
 
     val patches =
-      patchGenerator.generate(listOf(insertionLocalChange, updateLocalChange)).map {
+      patchGenerator.generate(listOf(insertionLocalChange, updateLocalChange), emptyList()).map {
         it.patchMappings.single()
       }
 
@@ -218,7 +210,7 @@ class PerResourcePatchGeneratorTest {
           .toLocalChange()
           .apply { LocalChangeToken(listOf(2)) },
       )
-    val patchToUpload = patchGenerator.generate(changes)
+    val patchToUpload = patchGenerator.generate(changes, emptyList())
 
     assertThat(patchToUpload).isEmpty()
   }
@@ -296,7 +288,7 @@ class PerResourcePatchGeneratorTest {
           .toLocalChange()
           .apply { LocalChangeToken(listOf(3)) },
       )
-    val patchToUpload = patchGenerator.generate(changes)
+    val patchToUpload = patchGenerator.generate(changes, emptyList())
 
     assertThat(patchToUpload).isEmpty()
   }
@@ -319,7 +311,7 @@ class PerResourcePatchGeneratorTest {
     val updatePatch = readJsonArrayFromFile("/update_patch_2.json")
 
     val patches =
-      patchGenerator.generate(listOf(updateLocalChange1, updateLocalChange2)).map {
+      patchGenerator.generate(listOf(updateLocalChange1, updateLocalChange2), emptyList()).map {
         it.patchMappings.single()
       }
 
@@ -367,7 +359,7 @@ class PerResourcePatchGeneratorTest {
         )
 
       val patches =
-        patchGenerator.generate(listOf(updatedLocalChange1, updatedLocalChange2)).map {
+        patchGenerator.generate(listOf(updatedLocalChange1, updatedLocalChange2), emptyList()).map {
           it.patchMappings.single()
         }
 
@@ -400,6 +392,7 @@ class PerResourcePatchGeneratorTest {
       patchGenerator
         .generate(
           listOf(updateLocalChange1, updateLocalChange2, deleteLocalChange),
+          emptyList(),
         )
         .map { it.patchMappings.single() }
 
@@ -448,7 +441,7 @@ class PerResourcePatchGeneratorTest {
       )
 
     val errorMessage =
-      assertFailsWith<IllegalArgumentException> { patchGenerator.generate(changes) }
+      assertFailsWith<IllegalArgumentException> { patchGenerator.generate(changes, emptyList()) }
         .localizedMessage
 
     assertThat(errorMessage).isEqualTo("Changes after deletion of resource are not permitted")
@@ -495,7 +488,7 @@ class PerResourcePatchGeneratorTest {
           .apply { LocalChangeToken(listOf(2)) },
       )
     val errorMessage =
-      assertFailsWith<IllegalArgumentException> { patchGenerator.generate(changes) }
+      assertFailsWith<IllegalArgumentException> { patchGenerator.generate(changes, emptyList()) }
         .localizedMessage
 
     assertThat(errorMessage).isEqualTo("Changes before creation of resource are not permitted")