diff --git a/src/main/java/graphql/incremental/IncrementalPayload.java b/src/main/java/graphql/incremental/IncrementalPayload.java
index 76b1fbb405..78f918fcf2 100644
--- a/src/main/java/graphql/incremental/IncrementalPayload.java
+++ b/src/main/java/graphql/incremental/IncrementalPayload.java
@@ -1,6 +1,5 @@
 package graphql.incremental;
 
-import graphql.ExecutionResult;
 import graphql.ExperimentalApi;
 import graphql.GraphQLError;
 import graphql.execution.ResultPath;
@@ -61,7 +60,7 @@ public Map<Object, Object> getExtensions() {
         return this.extensions;
     }
 
-    protected Map<String, Object> toSpecification() {
+    public Map<String, Object> toSpecification() {
         Map<String, Object> result = new LinkedHashMap<>();
 
         result.put("path", path);
@@ -122,25 +121,25 @@ public T errors(List<GraphQLError> errors) {
             return (T) this;
         }
 
-        public Builder<T> addErrors(List<GraphQLError> errors) {
+        public T addErrors(List<GraphQLError> errors) {
             this.errors.addAll(errors);
-            return this;
+            return (T) this;
         }
 
-        public Builder<T> addError(GraphQLError error) {
+        public T addError(GraphQLError error) {
             this.errors.add(error);
-            return this;
+            return (T) this;
         }
 
-        public Builder<T> extensions(Map<Object, Object> extensions) {
+        public T extensions(Map<Object, Object> extensions) {
             this.extensions = extensions;
-            return this;
+            return (T) this;
         }
 
-        public Builder<T> addExtension(String key, Object value) {
+        public T addExtension(String key, Object value) {
             this.extensions = (this.extensions == null ? new LinkedHashMap<>() : this.extensions);
             this.extensions.put(key, value);
-            return this;
+            return (T) this;
         }
     }
 }
diff --git a/src/test/groovy/graphql/incremental/DeferPayloadTest.groovy b/src/test/groovy/graphql/incremental/DeferPayloadTest.groovy
index 90d6a0899c..a37fa3ca71 100644
--- a/src/test/groovy/graphql/incremental/DeferPayloadTest.groovy
+++ b/src/test/groovy/graphql/incremental/DeferPayloadTest.groovy
@@ -1,6 +1,7 @@
 package graphql.incremental
 
-
+import graphql.GraphqlErrorBuilder
+import graphql.execution.ResultPath
 import spock.lang.Specification
 
 class DeferPayloadTest extends Specification {
@@ -14,8 +15,85 @@ class DeferPayloadTest extends Specification {
 
         then:
         spec == [
-                data      : null,
-                path      : null,
+                data: null,
+                path: null,
+        ]
+    }
+
+    def "can construct an instance using builder"() {
+        def payload = DeferPayload.newDeferredItem()
+                .data("twow is that a bee")
+                .path(["hello"])
+                .errors([])
+                .addError(GraphqlErrorBuilder.newError()
+                        .message("wow")
+                        .build())
+                .addErrors([
+                        GraphqlErrorBuilder.newError()
+                                .message("yep")
+                                .build(),
+                ])
+                .extensions([echo: "Hello world"])
+                .build()
+
+        when:
+        def serialized = payload.toSpecification()
+
+        then:
+        serialized == [
+                data      : "twow is that a bee",
+                path      : ["hello"],
+                errors    : [
+                        [
+                                message   : "wow",
+                                locations : [],
+                                extensions: [classification: "DataFetchingException"],
+                        ],
+                        [
+                                message   : "yep",
+                                locations : [],
+                                extensions: [classification: "DataFetchingException"],
+                        ],
+                ],
+                extensions: [
+                        echo: "Hello world",
+                ],
+        ]
+    }
+
+    def "errors replaces existing errors"() {
+        def payload = DeferPayload.newDeferredItem()
+                .data("twow is that a bee")
+                .path(ResultPath.fromList(["test", "echo"]))
+                .addError(GraphqlErrorBuilder.newError()
+                        .message("wow")
+                        .build())
+                .addErrors([])
+                .errors([
+                        GraphqlErrorBuilder.newError()
+                                .message("yep")
+                                .build(),
+                ])
+                .extensions([echo: "Hello world"])
+                .build()
+
+        when:
+        def serialized = payload.toSpecification()
+
+        then:
+        serialized == [
+                data      : "twow is that a bee",
+                errors    : [
+                        [
+                                message   : "yep",
+                                locations : [],
+                                extensions: [classification: "DataFetchingException"],
+                        ],
+                ],
+                extensions: [
+                        echo: "Hello world",
+                ],
+                path      : ["test", "echo"],
         ]
     }
 }
diff --git a/src/test/groovy/graphql/incremental/StreamPayloadTest.groovy b/src/test/groovy/graphql/incremental/StreamPayloadTest.groovy
index bee0d88631..7386cb8efd 100644
--- a/src/test/groovy/graphql/incremental/StreamPayloadTest.groovy
+++ b/src/test/groovy/graphql/incremental/StreamPayloadTest.groovy
@@ -1,5 +1,7 @@
 package graphql.incremental
 
+import graphql.GraphqlErrorBuilder
+import graphql.execution.ResultPath
 import spock.lang.Specification
 
 class StreamPayloadTest extends Specification {
@@ -17,4 +19,81 @@ class StreamPayloadTest extends Specification {
                 path : null,
         ]
     }
+
+    def "can construct an instance using builder"() {
+        def payload = StreamPayload.newStreamedItem()
+                .items(["twow is that a bee"])
+                .path(["hello"])
+                .errors([])
+                .addError(GraphqlErrorBuilder.newError()
+                        .message("wow")
+                        .build())
+                .addErrors([
+                        GraphqlErrorBuilder.newError()
+                                .message("yep")
+                                .build(),
+                ])
+                .extensions([echo: "Hello world"])
+                .build()
+
+        when:
+        def serialized = payload.toSpecification()
+
+        then:
+        serialized == [
+                items     : ["twow is that a bee"],
+                path      : ["hello"],
+                errors    : [
+                        [
+                                message   : "wow",
+                                locations : [],
+                                extensions: [classification: "DataFetchingException"],
+                        ],
+                        [
+                                message   : "yep",
+                                locations : [],
+                                extensions: [classification: "DataFetchingException"],
+                        ],
+                ],
+                extensions: [
+                        echo: "Hello world",
+                ],
+        ]
+    }
+
+    def "errors replaces existing errors"() {
+        def payload = StreamPayload.newStreamedItem()
+                .items(["twow is that a bee"])
+                .path(ResultPath.fromList(["test", "echo"]))
+                .addError(GraphqlErrorBuilder.newError()
+                        .message("wow")
+                        .build())
+                .addErrors([])
+                .errors([
+                        GraphqlErrorBuilder.newError()
+                                .message("yep")
+                                .build(),
+                ])
+                .extensions([echo: "Hello world"])
+                .build()
+
+        when:
+        def serialized = payload.toSpecification()
+
+        then:
+        serialized == [
+                items     : ["twow is that a bee"],
+                errors    : [
+                        [
+                                message   : "yep",
+                                locations : [],
+                                extensions: [classification: "DataFetchingException"],
+                        ],
+                ],
+                extensions: [
+                        echo: "Hello world",
+                ],
+                path      : ["test", "echo"],
+        ]
+    }
 }