diff --git a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/CollectionReference.java b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/CollectionReference.java
index a1cf52ba10de..3db5347425d2 100644
--- a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/CollectionReference.java
+++ b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/CollectionReference.java
@@ -23,6 +23,7 @@
 import com.google.api.gax.rpc.ApiExceptions;
 import com.google.cloud.firestore.v1.FirestoreClient.ListDocumentsPagedResponse;
 import com.google.common.base.Preconditions;
+import com.google.common.util.concurrent.MoreExecutors;
 import com.google.firestore.v1.Document;
 import com.google.firestore.v1.DocumentMask;
 import com.google.firestore.v1.ListDocumentsRequest;
@@ -187,7 +188,8 @@ public ApiFuture<DocumentReference> add(@Nonnull final Map<String, Object> field
           public DocumentReference apply(WriteResult writeResult) {
             return documentReference;
           }
-        });
+        },
+        MoreExecutors.directExecutor());
   }
 
   /**
diff --git a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/DocumentReference.java b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/DocumentReference.java
index 26ee1cfee022..054fe5a1ab30 100644
--- a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/DocumentReference.java
+++ b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/DocumentReference.java
@@ -22,6 +22,7 @@
 import com.google.api.gax.rpc.ApiException;
 import com.google.api.gax.rpc.ApiExceptions;
 import com.google.cloud.firestore.v1.FirestoreClient.ListCollectionIdsPagedResponse;
+import com.google.common.util.concurrent.MoreExecutors;
 import com.google.firestore.v1.ListCollectionIdsRequest;
 import java.util.Iterator;
 import java.util.List;
@@ -130,7 +131,8 @@ private <T> ApiFuture<T> extractFirst(ApiFuture<List<T>> results) {
           public T apply(List<T> results) {
             return results.isEmpty() ? null : results.get(0);
           }
-        });
+        },
+        MoreExecutors.directExecutor());
   }
 
   /**
diff --git a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Transaction.java b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Transaction.java
index 5daf2ef89cc8..13f51c0c7aec 100644
--- a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Transaction.java
+++ b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/Transaction.java
@@ -20,6 +20,7 @@
 import com.google.api.core.ApiFuture;
 import com.google.api.core.ApiFutures;
 import com.google.common.base.Preconditions;
+import com.google.common.util.concurrent.MoreExecutors;
 import com.google.firestore.v1.BeginTransactionRequest;
 import com.google.firestore.v1.BeginTransactionResponse;
 import com.google.firestore.v1.RollbackRequest;
@@ -93,7 +94,8 @@ public Void apply(BeginTransactionResponse beginTransactionResponse) {
             pending = true;
             return null;
           }
-        });
+        },
+        MoreExecutors.directExecutor());
   }
 
   /** Commits a transaction. */
@@ -120,7 +122,8 @@ ApiFuture<Void> rollback() {
           public Void apply(Empty beginTransactionResponse) {
             return null;
           }
-        });
+        },
+        MoreExecutors.directExecutor());
   }
 
   /**
@@ -140,7 +143,8 @@ public ApiFuture<DocumentSnapshot> get(@Nonnull DocumentReference documentRef) {
           public DocumentSnapshot apply(List<DocumentSnapshot> snapshots) {
             return snapshots.isEmpty() ? null : snapshots.get(0);
           }
-        });
+        },
+        MoreExecutors.directExecutor());
   }
 
   /**
diff --git a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/UpdateBuilder.java b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/UpdateBuilder.java
index b9be38743fe1..f342ad5c625f 100644
--- a/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/UpdateBuilder.java
+++ b/google-cloud-clients/google-cloud-firestore/src/main/java/com/google/cloud/firestore/UpdateBuilder.java
@@ -22,6 +22,7 @@
 import com.google.cloud.firestore.UserDataConverter.EncodingOptions;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableMap;
+import com.google.common.util.concurrent.MoreExecutors;
 import com.google.firestore.v1.CommitRequest;
 import com.google.firestore.v1.CommitResponse;
 import com.google.firestore.v1.Write;
@@ -657,7 +658,8 @@ public List<WriteResult> apply(CommitResponse commitResponse) {
 
             return result;
           }
-        });
+        },
+        MoreExecutors.directExecutor());
   }
 
   /** Checks whether any updates have been queued. */
diff --git a/google-cloud-clients/google-cloud-firestore/src/test/java/com/google/cloud/firestore/conformance/TestDefinition.java b/google-cloud-clients/google-cloud-firestore/src/test/java/com/google/cloud/firestore/conformance/TestDefinition.java
index 51a3af426e4b..c477050f468f 100644
--- a/google-cloud-clients/google-cloud-firestore/src/test/java/com/google/cloud/firestore/conformance/TestDefinition.java
+++ b/google-cloud-clients/google-cloud-firestore/src/test/java/com/google/cloud/firestore/conformance/TestDefinition.java
@@ -23098,7 +23098,7 @@ public int getKindValue() {
     /** <code>.tests.DocChange.Kind kind = 1;</code> */
     public com.google.cloud.firestore.conformance.TestDefinition.DocChange.Kind getKind() {
       com.google.cloud.firestore.conformance.TestDefinition.DocChange.Kind result =
-          com.google.cloud.firestore.conformance.TestDefinition.DocChange.Kind.valueOf(kind_);
+          com.google.cloud.firestore.conformance.TestDefinition.DocChange.Kind.forNumber(kind_);
       return result == null
           ? com.google.cloud.firestore.conformance.TestDefinition.DocChange.Kind.UNRECOGNIZED
           : result;
@@ -23510,7 +23510,7 @@ public Builder setKindValue(int value) {
       /** <code>.tests.DocChange.Kind kind = 1;</code> */
       public com.google.cloud.firestore.conformance.TestDefinition.DocChange.Kind getKind() {
         com.google.cloud.firestore.conformance.TestDefinition.DocChange.Kind result =
-            com.google.cloud.firestore.conformance.TestDefinition.DocChange.Kind.valueOf(kind_);
+            com.google.cloud.firestore.conformance.TestDefinition.DocChange.Kind.forNumber(kind_);
         return result == null
             ? com.google.cloud.firestore.conformance.TestDefinition.DocChange.Kind.UNRECOGNIZED
             : result;