diff --git a/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/fuzzer/fuzzer.go b/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/fuzzer/fuzzer.go
index fcde569686c..a7cfb0ae7cb 100644
--- a/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/fuzzer/fuzzer.go
+++ b/staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/fuzzer/fuzzer.go
@@ -60,22 +60,6 @@ func Funcs(codecs runtimeserializer.CodecFactory) []interface{} {
 					}
 					if isValue || c.Intn(10) == 0 {
 						c.Fuzz(vobj.Field(i).Addr().Interface())
-
-						// JSON keys must not contain escape char with our JSON codec (jsoniter)
-						// TODO: remove this when/if we moved from jsoniter.ConfigFastest to ConfigCompatibleWithStandardLibrary
-						if field.Type.Kind() == reflect.Map {
-							keys := append([]reflect.Value(nil), vobj.Field(i).MapKeys()...)
-							for _, k := range keys {
-								stripped := toJSONString(k.String())
-								if stripped == k.String() {
-									continue
-								}
-								// set new key
-								vobj.Field(i).SetMapIndex(reflect.ValueOf(stripped), vobj.Field(i).MapIndex(k))
-								// remove old
-								vobj.Field(i).SetMapIndex(k, reflect.Value{})
-							}
-						}
 					}
 				}
 			}
@@ -125,13 +109,3 @@ func Funcs(codecs runtimeserializer.CodecFactory) []interface{} {
 		},
 	}
 }
-
-func toJSONString(s string) string {
-	return strings.Map(func(r rune) rune {
-		// replace chars which are not supported in keys by jsoniter.ConfigFastest
-		if r == '\\' || r == '"' {
-			return 'x'
-		}
-		return r
-	}, s)
-}
diff --git a/staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/group_version_test.go b/staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/group_version_test.go
index 2217aa293d4..1f7f07e81d0 100644
--- a/staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/group_version_test.go
+++ b/staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/group_version_test.go
@@ -47,7 +47,7 @@ func TestGroupVersionUnmarshalJSON(t *testing.T) {
 			t.Errorf("JSON codec failed to unmarshal input '%s': expected %+v, got %+v", c.input, c.expect, result.GV)
 		}
 		// test the json-iterator codec
-		if err := jsoniter.ConfigFastest.Unmarshal(c.input, &result); err != nil {
+		if err := jsoniter.ConfigCompatibleWithStandardLibrary.Unmarshal(c.input, &result); err != nil {
 			t.Errorf("json-iterator codec failed to unmarshal input '%v': %v", c.input, err)
 		}
 		if !reflect.DeepEqual(result.GV, c.expect) {
diff --git a/staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/types_test.go b/staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/types_test.go
index 21aa9560e92..116f7505a42 100644
--- a/staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/types_test.go
+++ b/staging/src/k8s.io/apimachinery/pkg/apis/meta/v1/types_test.go
@@ -58,7 +58,7 @@ func TestVerbsUgorjiUnmarshalJSON(t *testing.T) {
 
 	for i, c := range cases {
 		var result APIResource
-		if err := jsoniter.ConfigFastest.Unmarshal([]byte(c.input), &result); err != nil {
+		if err := jsoniter.ConfigCompatibleWithStandardLibrary.Unmarshal([]byte(c.input), &result); err != nil {
 			t.Errorf("[%d] Failed to unmarshal input '%v': %v", i, c.input, err)
 		}
 		if !reflect.DeepEqual(result, c.result) {
diff --git a/staging/src/k8s.io/apimachinery/pkg/runtime/serializer/json/json.go b/staging/src/k8s.io/apimachinery/pkg/runtime/serializer/json/json.go
index 8a217f32e31..d3b37c75e3b 100644
--- a/staging/src/k8s.io/apimachinery/pkg/runtime/serializer/json/json.go
+++ b/staging/src/k8s.io/apimachinery/pkg/runtime/serializer/json/json.go
@@ -154,7 +154,7 @@ func (s *Serializer) Decode(originalData []byte, gvk *schema.GroupVersionKind, i
 		types, _, err := s.typer.ObjectKinds(into)
 		switch {
 		case runtime.IsNotRegisteredError(err), isUnstructured:
-			if err := jsoniter.ConfigFastest.Unmarshal(data, into); err != nil {
+			if err := jsoniter.ConfigCompatibleWithStandardLibrary.Unmarshal(data, into); err != nil {
 				return nil, actual, err
 			}
 			return into, actual, nil
@@ -188,7 +188,7 @@ func (s *Serializer) Decode(originalData []byte, gvk *schema.GroupVersionKind, i
 		return nil, actual, err
 	}
 
-	if err := jsoniter.ConfigFastest.Unmarshal(data, obj); err != nil {
+	if err := jsoniter.ConfigCompatibleWithStandardLibrary.Unmarshal(data, obj); err != nil {
 		return nil, actual, err
 	}
 	return obj, actual, nil
@@ -197,7 +197,7 @@ func (s *Serializer) Decode(originalData []byte, gvk *schema.GroupVersionKind, i
 // Encode serializes the provided object to the given writer.
 func (s *Serializer) Encode(obj runtime.Object, w io.Writer) error {
 	if s.yaml {
-		json, err := jsoniter.ConfigFastest.Marshal(obj)
+		json, err := jsoniter.ConfigCompatibleWithStandardLibrary.Marshal(obj)
 		if err != nil {
 			return err
 		}
@@ -210,7 +210,7 @@ func (s *Serializer) Encode(obj runtime.Object, w io.Writer) error {
 	}
 
 	if s.pretty {
-		data, err := jsoniter.ConfigFastest.MarshalIndent(obj, "", "  ")
+		data, err := jsoniter.ConfigCompatibleWithStandardLibrary.MarshalIndent(obj, "", "  ")
 		if err != nil {
 			return err
 		}