diff --git a/library/macos/FLEBasicMessageChannel.h b/library/macos/FLEBasicMessageChannel.h
new file mode 100644
index 000000000..7a2462437
--- /dev/null
+++ b/library/macos/FLEBasicMessageChannel.h
@@ -0,0 +1,70 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import <Foundation/Foundation.h>
+
+#import "FLEBinaryMessenger.h"
+#import "FLEMessageCodec.h"
+
+/**
+ * A message response callback. Used for sending a message's reply back to the Flutter engine.
+ * The reply must be serializable by the codec used to encode the message.
+ */
+typedef void (^FLEMessageReply)(id _Nullable reply);
+
+/**
+ * A handler for receiving a message. Implementations should asynchronously call |callback|
+ * exactly once with the reply to the message (or nil if there is none).
+ */
+typedef void (^FLEMessageHandler)(id _Nullable message, FLEMessageReply _Nonnull callback);
+
+/**
+ * A channel for communicating with the Flutter engine by sending asynchronous messages.
+ */
+@interface FLEBasicMessageChannel : NSObject
+
+// TODO: support +messageChannelWithName:binaryMessenger: once the standard codec is supported
+// (Issue #67).
+
+/**
+ * Returns a new channel that sends and receives messages on the channel named |name|, encoded
+ * with |codec| and dispatched via |messenger|.
+ */
++ (nonnull instancetype)messageChannelWithName:(nonnull NSString *)name
+                               binaryMessenger:(nonnull NSObject<FLEBinaryMessenger> *)messenger
+                                         codec:(nonnull NSObject<FLEMessageCodec> *)codec;
+
+/**
+ * Initializes a channel to send and receive messages on the channel named |name|, encoded
+ * with |codec| and dispatched via |messenger|.
+ */
+- (nonnull instancetype)initWithName:(nonnull NSString *)name
+                     binaryMessenger:(nonnull NSObject<FLEBinaryMessenger> *)messenger
+                               codec:(nonnull NSObject<FLEMessageCodec> *)codec;
+
+/**
+ * Sends a message to the Flutter engine on this channel.
+ *
+ * The message must be encodable using this channel's codec.
+ */
+- (void)sendMessage:(nullable id)message;
+
+// TODO: Support sendMessage:result: once
+// https://github.com/flutter/flutter/issues/18852 is resolved
+
+/**
+ * Registers a handler that should be called any time a message is received on this channel.
+ */
+- (void)setMessageHandler:(nullable FLEMessageHandler)handler;
+@end
diff --git a/library/macos/FLEBasicMessageChannel.m b/library/macos/FLEBasicMessageChannel.m
new file mode 100644
index 000000000..a20718caa
--- /dev/null
+++ b/library/macos/FLEBasicMessageChannel.m
@@ -0,0 +1,62 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import "FLEBasicMessageChannel.h"
+
+@implementation FLEBasicMessageChannel {
+  NSString *_name;
+  __weak id<FLEBinaryMessenger> _messenger;
+  id<FLEMessageCodec> _codec;
+}
++ (instancetype)messageChannelWithName:(NSString *)name
+                       binaryMessenger:(NSObject<FLEBinaryMessenger> *)messenger
+                                 codec:(NSObject<FLEMessageCodec> *)codec {
+  return [[[self class] alloc] initWithName:name binaryMessenger:messenger codec:codec];
+}
+
+- (instancetype)initWithName:(NSString *)name
+             binaryMessenger:(NSObject<FLEBinaryMessenger> *)messenger
+                       codec:(NSObject<FLEMessageCodec> *)codec {
+  self = [super init];
+  if (self) {
+    _name = [name copy];
+    _messenger = messenger;
+    _codec = codec;
+  }
+  return self;
+}
+
+- (void)sendMessage:(id)message {
+  [_messenger sendOnChannel:_name message:[_codec encode:message]];
+}
+
+- (void)setMessageHandler:(FLEMessageHandler)handler {
+  if (!handler) {
+    [_messenger setMessageHandlerOnChannel:_name binaryMessageHandler:nil];
+    return;
+  }
+
+  // Don't capture the channel in the callback, since that makes lifetimes harder to reason about.
+  id<FLEMessageCodec> codec = _codec;
+
+  FLEBinaryMessageHandler messageHandler = ^(NSData *message, FLEBinaryReply callback) {
+    handler([codec decode:message], ^(id reply) {
+      callback([codec encode:reply]);
+    });
+  };
+
+  [_messenger setMessageHandlerOnChannel:_name binaryMessageHandler:messageHandler];
+}
+
+@end
diff --git a/library/macos/FLEJSONMessageCodec.h b/library/macos/FLEJSONMessageCodec.h
new file mode 100644
index 000000000..ba5a50eec
--- /dev/null
+++ b/library/macos/FLEJSONMessageCodec.h
@@ -0,0 +1,24 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import <Foundation/Foundation.h>
+
+#import "FLEMessageCodec.h"
+
+/**
+ * A codec that uses JSON as the encoding format. Messages using this codec must be serializable
+ * to JSON.
+ */
+@interface FLEJSONMessageCodec : NSObject <FLEMessageCodec>
+@end
diff --git a/library/macos/FLEJSONMessageCodec.m b/library/macos/FLEJSONMessageCodec.m
new file mode 100644
index 000000000..585eb3c4f
--- /dev/null
+++ b/library/macos/FLEJSONMessageCodec.m
@@ -0,0 +1,67 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import "FLEJSONMessageCodec.h"
+
+@implementation FLEJSONMessageCodec
+
++ (instancetype)sharedInstance {
+  static FLEJSONMessageCodec *sharedInstance;
+  if (!sharedInstance) {
+    sharedInstance = [[FLEJSONMessageCodec alloc] init];
+  }
+  return sharedInstance;
+}
+
+- (NSData *)encode:(id)message {
+  if (!message) {
+    return nil;
+  }
+
+  NSData *encoding;
+  NSError *error = nil;
+  if ([message isKindOfClass:[NSArray class]] || [message isKindOfClass:[NSDictionary class]]) {
+    encoding = [NSJSONSerialization dataWithJSONObject:message options:0 error:&error];
+  } else {
+    // Wrap then unwrap non-collection objects; see FlutterCodecs.mm in the Flutter engine.
+    encoding = [NSJSONSerialization dataWithJSONObject:@[ message ] options:0 error:&error];
+    const NSUInteger kJSONArrayStartLength = 1;
+    const NSUInteger kJSONArrayEndLength = 1;
+    encoding = [encoding subdataWithRange:NSMakeRange(kJSONArrayStartLength,
+                                                      encoding.length - (kJSONArrayStartLength +
+                                                                         kJSONArrayEndLength))];
+  }
+  if (error) {
+    NSLog(@"Error: Failed to create JSON message for %@: %@", message, error.debugDescription);
+  }
+  return encoding;
+}
+
+// See FlutterCodecs.mm in the Flutter engine for implementation notes.
+- (id)decode:(NSData *)messageData {
+  if (!messageData) {
+    return nil;
+  }
+
+  NSError *error = nil;
+  id message = [NSJSONSerialization JSONObjectWithData:messageData
+                                               options:NSJSONReadingAllowFragments
+                                                 error:&error];
+  if (error) {
+    NSLog(@"Error: Failed to decode JSON message: %@", error.debugDescription);
+  }
+  return message;
+}
+
+@end
diff --git a/library/macos/FLEJSONMethodCodec.h b/library/macos/FLEJSONMethodCodec.h
new file mode 100644
index 000000000..2f1f8c03b
--- /dev/null
+++ b/library/macos/FLEJSONMethodCodec.h
@@ -0,0 +1,24 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import <Foundation/Foundation.h>
+
+#import "FLEMethodCodec.h"
+
+/**
+ * A codec that uses JSON as the encoding format. Method arguments and error details for plugins
+ * using this codec must be serializable to JSON.
+ */
+@interface FLEJSONMethodCodec : NSObject <FLEMethodCodec>
+@end
diff --git a/library/macos/FLECodecs.m b/library/macos/FLEJSONMethodCodec.m
similarity index 97%
rename from library/macos/FLECodecs.m
rename to library/macos/FLEJSONMethodCodec.m
index 6f89a93a8..945f986cc 100644
--- a/library/macos/FLECodecs.m
+++ b/library/macos/FLEJSONMethodCodec.m
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#import "FLECodecs.h"
+#import "FLEJSONMethodCodec.h"
 
 // Keys for JSON-encoded method calls.
 static NSString *const kMessageMethodKey = @"method";
@@ -70,7 +70,7 @@ - (FLEMethodCall *)decodeMethodCall:(NSData *)methodData {
   return [[FLEMethodCall alloc] initWithMethodName:method arguments:arguments];
 }
 
-- (NSData *)encodeSuccessEnvelope:(id _Nullable)result {
+- (NSData *)encodeSuccessEnvelope:(id)result {
   return SerializeAsJSON(@[ result ?: [NSNull null] ]);
 }
 
diff --git a/library/macos/FLEMessageCodec.h b/library/macos/FLEMessageCodec.h
new file mode 100644
index 000000000..15d5ca64e
--- /dev/null
+++ b/library/macos/FLEMessageCodec.h
@@ -0,0 +1,38 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import <Foundation/Foundation.h>
+
+/**
+ * Translates between a binary message and higher-level message objects.
+ */
+@protocol FLEMessageCodec
+
+/**
+ * Returns the shared instance of the codec.
+ */
++ (nonnull instancetype)sharedInstance;
+
+/**
+ * Returns a binary encoding of the given |message|, or nil if the message cannot be
+ * serialized by this codec.
+ */
+- (nullable NSData*)encode:(nullable id)message;
+
+/**
+ * Returns the decoded mesasge, or nil if it cannot be decoded.
+ */
+- (nullable id)decode:(nullable NSData*)messageData;
+
+@end
diff --git a/library/macos/FLEMethodCall.h b/library/macos/FLEMethodCall.h
new file mode 100644
index 000000000..0bd697054
--- /dev/null
+++ b/library/macos/FLEMethodCall.h
@@ -0,0 +1,43 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import <Foundation/Foundation.h>
+
+/**
+ * An object encapsulating a method call from Flutter.
+ */
+@interface FLEMethodCall : NSObject
+
+/**
+ * Initializes an FLEMethodCall. If |arguments| is provided, it must be serializable by the codec
+ * used to encode the call.
+ */
+- (nonnull instancetype)initWithMethodName:(nonnull NSString *)name
+                                 arguments:(nullable id)arguments NS_DESIGNATED_INITIALIZER;
+
+- (nonnull instancetype)init NS_UNAVAILABLE;
+
+/**
+ * The name of the method being called.
+ */
+@property(readonly, nonatomic, nonnull) NSString *methodName;
+
+/**
+ * The arguments to the method being called, if any.
+ *
+ * This object must be serializable by the codec used to encode the call.
+ */
+@property(readonly, nonatomic, nullable) id arguments;
+
+@end
diff --git a/library/macos/FLEMethodCall.m b/library/macos/FLEMethodCall.m
new file mode 100644
index 000000000..35d263365
--- /dev/null
+++ b/library/macos/FLEMethodCall.m
@@ -0,0 +1,28 @@
+// Copyright 2018 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#import "FLEMethodCall.h"
+
+@implementation FLEMethodCall
+
+- (instancetype)initWithMethodName:(NSString *)name arguments:(id)arguments {
+  self = [super init];
+  if (self) {
+    _methodName = name;
+    _arguments = arguments;
+  }
+  return self;
+}
+
+@end
diff --git a/library/macos/FLEChannels.h b/library/macos/FLEMethodChannel.h
similarity index 91%
rename from library/macos/FLEChannels.h
rename to library/macos/FLEMethodChannel.h
index 641229699..98dca1b7d 100644
--- a/library/macos/FLEChannels.h
+++ b/library/macos/FLEMethodChannel.h
@@ -15,8 +15,7 @@
 #import <Foundation/Foundation.h>
 
 #import "FLEBinaryMessenger.h"
-#import "FLECodecs.h"
-#import "FLEMethods.h"
+#import "FLEMethodCodec.h"
 
 /**
  * A method call result callback. Used for sending a method call's response back to the
@@ -50,14 +49,15 @@ extern NSString const *_Nonnull FLEMethodNotImplemented;
 // (Issue #67).
 
 /**
- * Returns a new channel that sends and receives method calls on the channel name |name|, encoded
+ * Returns a new channel that sends and receives method calls on the channel named |name|, encoded
  * with |codec| and dispatched via |messenger|.
  */
 + (nonnull instancetype)methodChannelWithName:(nonnull NSString *)name
                               binaryMessenger:(nonnull id<FLEBinaryMessenger>)messenger
                                         codec:(nonnull id<FLEMethodCodec>)codec;
+
 /**
- * Initializes a channel to send and receive method calls on the channel name |name|, encoded
+ * Initializes a channel to send and receive method calls on the channel named |name|, encoded
  * with |codec| and dispatched via |messenger|.
  */
 - (nonnull instancetype)initWithName:(nonnull NSString *)name
@@ -69,7 +69,7 @@ extern NSString const *_Nonnull FLEMethodNotImplemented;
  *
  * The arguments, if any, must be encodable using this channel's codec.
  */
-- (void)invokeMethod:(nonnull NSString *)method arguments:(id _Nullable)arguments;
+- (void)invokeMethod:(nonnull NSString *)method arguments:(nullable id)arguments;
 
 // TODO: Support invokeMethod:arguments:result: once
 // https://github.com/flutter/flutter/issues/18852 is resolved
@@ -77,6 +77,6 @@ extern NSString const *_Nonnull FLEMethodNotImplemented;
 /**
  * Registers a handler that should be called any time a method call is received on this channel.
  */
-- (void)setMethodCallHandler:(FLEMethodCallHandler _Nullable)handler;
+- (void)setMethodCallHandler:(nullable FLEMethodCallHandler)handler;
 
 @end
diff --git a/library/macos/FLEChannels.m b/library/macos/FLEMethodChannel.m
similarity index 80%
rename from library/macos/FLEChannels.m
rename to library/macos/FLEMethodChannel.m
index 6708da9d8..f279aac93 100644
--- a/library/macos/FLEChannels.m
+++ b/library/macos/FLEMethodChannel.m
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#import "FLEChannels.h"
+#import "FLEMethodChannel.h"
 
 NSString const *FLEMethodNotImplemented = @"notimplemented";
 
@@ -22,15 +22,15 @@ @implementation FLEMethodChannel {
   id<FLEMethodCodec> _codec;
 }
 
-+ (instancetype)methodChannelWithName:(nonnull NSString *)name
-                      binaryMessenger:(nonnull id<FLEBinaryMessenger>)messenger
-                                codec:(nonnull NSObject<FLEMethodCodec> *)codec {
++ (instancetype)methodChannelWithName:(NSString *)name
+                      binaryMessenger:(id<FLEBinaryMessenger>)messenger
+                                codec:(NSObject<FLEMethodCodec> *)codec {
   return [[[self class] alloc] initWithName:name binaryMessenger:messenger codec:codec];
 }
 
-- (instancetype)initWithName:(nonnull NSString *)name
-             binaryMessenger:(nonnull id<FLEBinaryMessenger>)messenger
-                       codec:(nonnull id<FLEMethodCodec>)codec {
+- (instancetype)initWithName:(NSString *)name
+             binaryMessenger:(id<FLEBinaryMessenger>)messenger
+                       codec:(id<FLEMethodCodec>)codec {
   self = [super init];
   if (self) {
     _name = [name copy];
@@ -40,7 +40,7 @@ - (instancetype)initWithName:(nonnull NSString *)name
   return self;
 }
 
-- (void)invokeMethod:(NSString *)method arguments:(id _Nullable)arguments {
+- (void)invokeMethod:(NSString *)method arguments:(id)arguments {
   FLEMethodCall *methodCall = [[FLEMethodCall alloc] initWithMethodName:method arguments:arguments];
   NSData *message = [_codec encodeMethodCall:methodCall];
   if (!message) {
@@ -50,7 +50,7 @@ - (void)invokeMethod:(NSString *)method arguments:(id _Nullable)arguments {
   [_messenger sendOnChannel:_name message:message];
 }
 
-- (void)setMethodCallHandler:(FLEMethodCallHandler _Nullable)handler {
+- (void)setMethodCallHandler:(FLEMethodCallHandler)handler {
   if (!handler) {
     [_messenger setMessageHandlerOnChannel:_name binaryMessageHandler:nil];
     return;
diff --git a/library/macos/FLECodecs.h b/library/macos/FLEMethodCodec.h
similarity index 84%
rename from library/macos/FLECodecs.h
rename to library/macos/FLEMethodCodec.h
index ec6f722a1..9d25148ca 100644
--- a/library/macos/FLECodecs.h
+++ b/library/macos/FLEMethodCodec.h
@@ -14,7 +14,8 @@
 
 #import <Foundation/Foundation.h>
 
-#import "FLEMethods.h"
+#import "FLEMethodCall.h"
+#import "FLEMethodError.h"
 
 /**
  * Translates between a binary message and higher-level method call and response/error objects.
@@ -50,12 +51,3 @@
 - (nullable NSData*)encodeErrorEnvelope:(nonnull FLEMethodError*)error;
 
 @end
-
-/**
- * A codec that uses JSON as the encoding format. Method arguments and error details for plugins
- * using this codec must be serializable to JSON.
- */
-@interface FLEJSONMethodCodec : NSObject <FLEMethodCodec>
-@end
-
-// TODO: Implement the other core Flutter codecs. Issue #67.
diff --git a/library/macos/FLEMethods.h b/library/macos/FLEMethodError.h
similarity index 66%
rename from library/macos/FLEMethods.h
rename to library/macos/FLEMethodError.h
index f36a15db3..6a8ac79aa 100644
--- a/library/macos/FLEMethods.h
+++ b/library/macos/FLEMethodError.h
@@ -14,35 +14,6 @@
 
 #import <Foundation/Foundation.h>
 
-/**
- * An object encapsulating a method call from Flutter.
- */
-@interface FLEMethodCall : NSObject
-
-/**
- * Initializes an FLEMethodCall. If |arguments| is provided, it must be serializable by the codec
- * used to encode the call.
- */
-- (nonnull instancetype)initWithMethodName:(nonnull NSString *)name
-                                 arguments:(nullable id)arguments NS_DESIGNATED_INITIALIZER;
-- (nonnull instancetype)init NS_UNAVAILABLE;
-
-/**
- * The name of the method being called.
- */
-@property(readonly, nonatomic, nonnull) NSString *methodName;
-
-/**
- * The arguments to the method being called, if any.
- *
- * This object must be serializable by the codec used to encode the call.
- */
-@property(readonly, nonatomic, nullable) id arguments;
-
-@end
-
-#pragma mark -
-
 /**
  * An error object that can be passed to an FLEMethodResult to send an error response to the caller
  * on the Flutter side.
@@ -55,6 +26,7 @@
 - (nonnull instancetype)initWithCode:(nonnull NSString *)code
                              message:(nullable NSString *)message
                              details:(nullable id)details NS_DESIGNATED_INITIALIZER;
+
 - (nonnull instancetype)init NS_UNAVAILABLE;
 
 /**
diff --git a/library/macos/FLEMethods.m b/library/macos/FLEMethodError.m
similarity index 59%
rename from library/macos/FLEMethods.m
rename to library/macos/FLEMethodError.m
index ac3481089..20ffe8b75 100644
--- a/library/macos/FLEMethods.m
+++ b/library/macos/FLEMethodError.m
@@ -12,29 +12,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#import "FLEMethods.h"
-
-@implementation FLEMethodCall
-
-- (nonnull instancetype)initWithMethodName:(nonnull NSString *)name
-                                 arguments:(nullable id)arguments {
-  self = [super init];
-  if (self) {
-    _methodName = name;
-    _arguments = arguments;
-  }
-  return self;
-}
-
-@end
-
-#pragma mark -
+#import "FLEMethodError.h"
 
 @implementation FLEMethodError
 
-- (nonnull instancetype)initWithCode:(nonnull NSString *)code
-                             message:(nullable NSString *)message
-                             details:(nullable id)details {
+- (instancetype)initWithCode:(NSString *)code message:(NSString *)message details:(id)details {
   self = [super init];
   if (self) {
     _code = code;
diff --git a/library/macos/FLEPlugin.h b/library/macos/FLEPlugin.h
index d5b57b987..cad50efa4 100644
--- a/library/macos/FLEPlugin.h
+++ b/library/macos/FLEPlugin.h
@@ -14,8 +14,9 @@
 
 #import <Foundation/Foundation.h>
 
-#import "FLEChannels.h"
-#import "FLECodecs.h"
+#import "FLEMethodCall.h"
+#import "FLEMethodChannel.h"
+#import "FLEMethodCodec.h"
 
 @class FLEViewController;
 
diff --git a/library/macos/FLEViewController.h b/library/macos/FLEViewController.h
index 74a2e05a4..51b6ac12e 100644
--- a/library/macos/FLEViewController.h
+++ b/library/macos/FLEViewController.h
@@ -14,7 +14,7 @@
 
 #import <Cocoa/Cocoa.h>
 
-#import "FLECodecs.h"
+#import "FLEMethodCodec.h"
 #import "FLEOpenGLContextHandling.h"
 #import "FLEPlugin.h"
 #import "FLEReshapeListener.h"
diff --git a/library/macos/FlutterEmbedderMac.h b/library/macos/FlutterEmbedderMac.h
index 5ca66a6b7..18ccefa39 100644
--- a/library/macos/FlutterEmbedderMac.h
+++ b/library/macos/FlutterEmbedderMac.h
@@ -12,10 +12,15 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+#import "FLEBasicMessageChannel.h"
 #import "FLEBinaryMessenger.h"
-#import "FLEChannels.h"
-#import "FLECodecs.h"
-#import "FLEMethods.h"
+#import "FLEJSONMessageCodec.h"
+#import "FLEJSONMethodCodec.h"
+#import "FLEMessageCodec.h"
+#import "FLEMethodCall.h"
+#import "FLEMethodChannel.h"
+#import "FLEMethodCodec.h"
+#import "FLEMethodError.h"
 #import "FLEOpenGLContextHandling.h"
 #import "FLEPlugin.h"
 #import "FLEReshapeListener.h"
diff --git a/library/macos/FlutterEmbedderMac.xcodeproj/project.pbxproj b/library/macos/FlutterEmbedderMac.xcodeproj/project.pbxproj
index 18309c0b8..0b730ac53 100644
--- a/library/macos/FlutterEmbedderMac.xcodeproj/project.pbxproj
+++ b/library/macos/FlutterEmbedderMac.xcodeproj/project.pbxproj
@@ -31,12 +31,20 @@
 		1EEF8E071FD1F0C300DD563C /* FLEView.h in Headers */ = {isa = PBXBuildFile; fileRef = 1EEF8E051FD1F0C300DD563C /* FLEView.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		1EEF8E081FD1F0C300DD563C /* FLEView.m in Sources */ = {isa = PBXBuildFile; fileRef = 1EEF8E061FD1F0C300DD563C /* FLEView.m */; };
 		3389A6872159359200A27898 /* FLEBinaryMessenger.h in Headers */ = {isa = PBXBuildFile; fileRef = 3389A6862159359200A27898 /* FLEBinaryMessenger.h */; settings = {ATTRIBUTES = (Public, ); }; };
-		3389A68D215949CB00A27898 /* FLEMethods.m in Sources */ = {isa = PBXBuildFile; fileRef = 3389A68C215949CB00A27898 /* FLEMethods.m */; };
-		3389A68F215949D600A27898 /* FLEMethods.h in Headers */ = {isa = PBXBuildFile; fileRef = 3389A68E215949D600A27898 /* FLEMethods.h */; settings = {ATTRIBUTES = (Public, ); }; };
-		33A87EB620F6BCDB0086D21D /* FLECodecs.h in Headers */ = {isa = PBXBuildFile; fileRef = 33A87EB420F6BCDB0086D21D /* FLECodecs.h */; settings = {ATTRIBUTES = (Public, ); }; };
-		33A87EB720F6BCDB0086D21D /* FLECodecs.m in Sources */ = {isa = PBXBuildFile; fileRef = 33A87EB520F6BCDB0086D21D /* FLECodecs.m */; };
-		33D7B59920A4F54400296EFC /* FLEChannels.h in Headers */ = {isa = PBXBuildFile; fileRef = 33D7B59720A4F54400296EFC /* FLEChannels.h */; settings = {ATTRIBUTES = (Public, ); }; };
-		33D7B59A20A4F54400296EFC /* FLEChannels.m in Sources */ = {isa = PBXBuildFile; fileRef = 33D7B59820A4F54400296EFC /* FLEChannels.m */; };
+		3389A68D215949CB00A27898 /* FLEMethodError.m in Sources */ = {isa = PBXBuildFile; fileRef = 3389A68C215949CB00A27898 /* FLEMethodError.m */; };
+		3389A68F215949D600A27898 /* FLEMethodError.h in Headers */ = {isa = PBXBuildFile; fileRef = 3389A68E215949D600A27898 /* FLEMethodError.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		33A87EB620F6BCDB0086D21D /* FLEMethodCodec.h in Headers */ = {isa = PBXBuildFile; fileRef = 33A87EB420F6BCDB0086D21D /* FLEMethodCodec.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		33A87EB720F6BCDB0086D21D /* FLEJSONMethodCodec.m in Sources */ = {isa = PBXBuildFile; fileRef = 33A87EB520F6BCDB0086D21D /* FLEJSONMethodCodec.m */; };
+		33C0FA1A21B845F0008F8959 /* FLEBasicMessageChannel.m in Sources */ = {isa = PBXBuildFile; fileRef = 33C0FA1821B845EF008F8959 /* FLEBasicMessageChannel.m */; };
+		33C0FA1B21B845F0008F8959 /* FLEBasicMessageChannel.h in Headers */ = {isa = PBXBuildFile; fileRef = 33C0FA1921B845F0008F8959 /* FLEBasicMessageChannel.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		33C0FA2021B84810008F8959 /* FLEJSONMessageCodec.m in Sources */ = {isa = PBXBuildFile; fileRef = 33C0FA1C21B84810008F8959 /* FLEJSONMessageCodec.m */; };
+		33C0FA2121B84810008F8959 /* FLEJSONMethodCodec.h in Headers */ = {isa = PBXBuildFile; fileRef = 33C0FA1D21B84810008F8959 /* FLEJSONMethodCodec.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		33C0FA2221B84810008F8959 /* FLEJSONMessageCodec.h in Headers */ = {isa = PBXBuildFile; fileRef = 33C0FA1E21B84810008F8959 /* FLEJSONMessageCodec.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		33C0FA2321B84810008F8959 /* FLEMessageCodec.h in Headers */ = {isa = PBXBuildFile; fileRef = 33C0FA1F21B84810008F8959 /* FLEMessageCodec.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		33C0FA2621B84AA4008F8959 /* FLEMethodCall.h in Headers */ = {isa = PBXBuildFile; fileRef = 33C0FA2421B84AA4008F8959 /* FLEMethodCall.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		33C0FA2721B84AA4008F8959 /* FLEMethodCall.m in Sources */ = {isa = PBXBuildFile; fileRef = 33C0FA2521B84AA4008F8959 /* FLEMethodCall.m */; };
+		33D7B59920A4F54400296EFC /* FLEMethodChannel.h in Headers */ = {isa = PBXBuildFile; fileRef = 33D7B59720A4F54400296EFC /* FLEMethodChannel.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		33D7B59A20A4F54400296EFC /* FLEMethodChannel.m in Sources */ = {isa = PBXBuildFile; fileRef = 33D7B59820A4F54400296EFC /* FLEMethodChannel.m */; };
 		33E202A5212BC0A800337F48 /* FLETextInputPlugin.h in Headers */ = {isa = PBXBuildFile; fileRef = 1E2492331FCF50BE00DD3BBB /* FLETextInputPlugin.h */; };
 		33E202A6212BC0ED00337F48 /* FLEKeyEventPlugin.h in Headers */ = {isa = PBXBuildFile; fileRef = 64C76C2620D7BDFB00B16256 /* FLEKeyEventPlugin.h */; };
 		33E202A7212BC0F100337F48 /* FLEViewController+Internal.h in Headers */ = {isa = PBXBuildFile; fileRef = 6442F82C20EA6C5F00A393AE /* FLEViewController+Internal.h */; };
@@ -84,13 +92,21 @@
 		1EEF8E051FD1F0C300DD563C /* FLEView.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = FLEView.h; sourceTree = "<group>"; };
 		1EEF8E061FD1F0C300DD563C /* FLEView.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = FLEView.m; sourceTree = "<group>"; };
 		3389A6862159359200A27898 /* FLEBinaryMessenger.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = FLEBinaryMessenger.h; sourceTree = "<group>"; };
-		3389A68C215949CB00A27898 /* FLEMethods.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = FLEMethods.m; sourceTree = "<group>"; };
-		3389A68E215949D600A27898 /* FLEMethods.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = FLEMethods.h; sourceTree = "<group>"; };
-		33A87EB420F6BCDB0086D21D /* FLECodecs.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FLECodecs.h; sourceTree = "<group>"; };
-		33A87EB520F6BCDB0086D21D /* FLECodecs.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = FLECodecs.m; sourceTree = "<group>"; };
+		3389A68C215949CB00A27898 /* FLEMethodError.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = FLEMethodError.m; sourceTree = "<group>"; };
+		3389A68E215949D600A27898 /* FLEMethodError.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = FLEMethodError.h; sourceTree = "<group>"; };
+		33A87EB420F6BCDB0086D21D /* FLEMethodCodec.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FLEMethodCodec.h; sourceTree = "<group>"; };
+		33A87EB520F6BCDB0086D21D /* FLEJSONMethodCodec.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = FLEJSONMethodCodec.m; sourceTree = "<group>"; };
 		33B1650F201A5F7D00732DC9 /* FlutterEmbedder.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = FlutterEmbedder.framework; path = ../../../flutter_engine_framework/macos/FlutterEmbedder.framework; sourceTree = SOURCE_ROOT; };
-		33D7B59720A4F54400296EFC /* FLEChannels.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FLEChannels.h; sourceTree = "<group>"; };
-		33D7B59820A4F54400296EFC /* FLEChannels.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = FLEChannels.m; sourceTree = "<group>"; };
+		33C0FA1821B845EF008F8959 /* FLEBasicMessageChannel.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = FLEBasicMessageChannel.m; sourceTree = "<group>"; };
+		33C0FA1921B845F0008F8959 /* FLEBasicMessageChannel.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = FLEBasicMessageChannel.h; sourceTree = "<group>"; };
+		33C0FA1C21B84810008F8959 /* FLEJSONMessageCodec.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = FLEJSONMessageCodec.m; sourceTree = "<group>"; };
+		33C0FA1D21B84810008F8959 /* FLEJSONMethodCodec.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = FLEJSONMethodCodec.h; sourceTree = "<group>"; };
+		33C0FA1E21B84810008F8959 /* FLEJSONMessageCodec.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = FLEJSONMessageCodec.h; sourceTree = "<group>"; };
+		33C0FA1F21B84810008F8959 /* FLEMessageCodec.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = FLEMessageCodec.h; sourceTree = "<group>"; };
+		33C0FA2421B84AA4008F8959 /* FLEMethodCall.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = FLEMethodCall.h; sourceTree = "<group>"; };
+		33C0FA2521B84AA4008F8959 /* FLEMethodCall.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = FLEMethodCall.m; sourceTree = "<group>"; };
+		33D7B59720A4F54400296EFC /* FLEMethodChannel.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FLEMethodChannel.h; sourceTree = "<group>"; };
+		33D7B59820A4F54400296EFC /* FLEMethodChannel.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = FLEMethodChannel.m; sourceTree = "<group>"; };
 		6442F82C20EA6C5F00A393AE /* FLEViewController+Internal.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "FLEViewController+Internal.h"; sourceTree = "<group>"; };
 		64C76C2620D7BDFB00B16256 /* FLEKeyEventPlugin.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FLEKeyEventPlugin.h; sourceTree = "<group>"; };
 		64C76C2720D7BE2E00B16256 /* FLEKeyEventPlugin.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = FLEKeyEventPlugin.m; sourceTree = "<group>"; };
@@ -117,15 +133,18 @@
 				C4C1FE431FD74F6400691968 /* FlutterEmbedder.framework */,
 				1E2492371FCF50BE00DD3BBB /* FlutterEmbedderMac.h */,
 				1E2492451FCF536200DD3BBB /* Public */,
-				33D7B59820A4F54400296EFC /* FLEChannels.m */,
-				33A87EB520F6BCDB0086D21D /* FLECodecs.m */,
-				3389A68C215949CB00A27898 /* FLEMethods.m */,
+				33C0FA1821B845EF008F8959 /* FLEBasicMessageChannel.m */,
+				33C0FA1C21B84810008F8959 /* FLEJSONMessageCodec.m */,
+				33A87EB520F6BCDB0086D21D /* FLEJSONMethodCodec.m */,
+				64C76C2620D7BDFB00B16256 /* FLEKeyEventPlugin.h */,
+				64C76C2720D7BE2E00B16256 /* FLEKeyEventPlugin.m */,
+				33C0FA2521B84AA4008F8959 /* FLEMethodCall.m */,
+				33D7B59820A4F54400296EFC /* FLEMethodChannel.m */,
+				3389A68C215949CB00A27898 /* FLEMethodError.m */,
 				AA8AE8B71FD948AC00B6FB31 /* FLETextInputModel.h */,
 				AA8AE8B91FD948BA00B6FB31 /* FLETextInputModel.m */,
 				1E2492331FCF50BE00DD3BBB /* FLETextInputPlugin.h */,
 				1E2492341FCF50BE00DD3BBB /* FLETextInputPlugin.m */,
-				64C76C2620D7BDFB00B16256 /* FLEKeyEventPlugin.h */,
-				64C76C2720D7BE2E00B16256 /* FLEKeyEventPlugin.m */,
 				1EEF8E061FD1F0C300DD563C /* FLEView.m */,
 				6442F82C20EA6C5F00A393AE /* FLEViewController+Internal.h */,
 				1E2492361FCF50BE00DD3BBB /* FLEViewController.m */,
@@ -146,10 +165,15 @@
 		1E2492451FCF536200DD3BBB /* Public */ = {
 			isa = PBXGroup;
 			children = (
+				33C0FA1921B845F0008F8959 /* FLEBasicMessageChannel.h */,
 				3389A6862159359200A27898 /* FLEBinaryMessenger.h */,
-				33D7B59720A4F54400296EFC /* FLEChannels.h */,
-				33A87EB420F6BCDB0086D21D /* FLECodecs.h */,
-				3389A68E215949D600A27898 /* FLEMethods.h */,
+				33C0FA1E21B84810008F8959 /* FLEJSONMessageCodec.h */,
+				33C0FA1D21B84810008F8959 /* FLEJSONMethodCodec.h */,
+				33C0FA1F21B84810008F8959 /* FLEMessageCodec.h */,
+				33C0FA2421B84AA4008F8959 /* FLEMethodCall.h */,
+				33D7B59720A4F54400296EFC /* FLEMethodChannel.h */,
+				33A87EB420F6BCDB0086D21D /* FLEMethodCodec.h */,
+				3389A68E215949D600A27898 /* FLEMethodError.h */,
 				1E24922F1FCF50BE00DD3BBB /* FLEOpenGLContextHandling.h */,
 				1E2492311FCF50BE00DD3BBB /* FLEPlugin.h */,
 				1E2492321FCF50BE00DD3BBB /* FLEReshapeListener.h */,
@@ -175,20 +199,24 @@
 			buildActionMask = 2147483647;
 			files = (
 				33E202A6212BC0ED00337F48 /* FLEKeyEventPlugin.h in Headers */,
+				33C0FA2621B84AA4008F8959 /* FLEMethodCall.h in Headers */,
 				1E24923B1FCF50BE00DD3BBB /* FLEPlugin.h in Headers */,
 				3389A6872159359200A27898 /* FLEBinaryMessenger.h in Headers */,
-				33D7B59920A4F54400296EFC /* FLEChannels.h in Headers */,
+				33D7B59920A4F54400296EFC /* FLEMethodChannel.h in Headers */,
 				1E24923F1FCF50BE00DD3BBB /* FLEViewController.h in Headers */,
 				33E202A5212BC0A800337F48 /* FLETextInputPlugin.h in Headers */,
 				1E2492411FCF50BE00DD3BBB /* FlutterEmbedderMac.h in Headers */,
 				1E2492391FCF50BE00DD3BBB /* FLEOpenGLContextHandling.h in Headers */,
+				33C0FA1B21B845F0008F8959 /* FLEBasicMessageChannel.h in Headers */,
+				33C0FA2321B84810008F8959 /* FLEMessageCodec.h in Headers */,
 				1E24923C1FCF50BE00DD3BBB /* FLEReshapeListener.h in Headers */,
-				3389A689215935A100A27898 /* FLEMethods.h in Headers */,
+				33C0FA2121B84810008F8959 /* FLEJSONMethodCodec.h in Headers */,
 				33E202A7212BC0F100337F48 /* FLEViewController+Internal.h in Headers */,
 				AA8AE8B81FD948AC00B6FB31 /* FLETextInputModel.h in Headers */,
 				1EEF8E071FD1F0C300DD563C /* FLEView.h in Headers */,
-				33A87EB620F6BCDB0086D21D /* FLECodecs.h in Headers */,
-				3389A68F215949D600A27898 /* FLEMethods.h in Headers */,
+				33C0FA2221B84810008F8959 /* FLEJSONMessageCodec.h in Headers */,
+				33A87EB620F6BCDB0086D21D /* FLEMethodCodec.h in Headers */,
+				3389A68F215949D600A27898 /* FLEMethodError.h in Headers */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -283,13 +311,16 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				33D7B59A20A4F54400296EFC /* FLEChannels.m in Sources */,
+				33D7B59A20A4F54400296EFC /* FLEMethodChannel.m in Sources */,
 				1E2492401FCF50BE00DD3BBB /* FLEViewController.m in Sources */,
-				3389A68D215949CB00A27898 /* FLEMethods.m in Sources */,
+				3389A68D215949CB00A27898 /* FLEMethodError.m in Sources */,
 				64C76C2820D7BE2E00B16256 /* FLEKeyEventPlugin.m in Sources */,
+				33C0FA2721B84AA4008F8959 /* FLEMethodCall.m in Sources */,
+				33C0FA2021B84810008F8959 /* FLEJSONMessageCodec.m in Sources */,
+				33C0FA1A21B845F0008F8959 /* FLEBasicMessageChannel.m in Sources */,
 				1E24923E1FCF50BE00DD3BBB /* FLETextInputPlugin.m in Sources */,
 				1EEF8E081FD1F0C300DD563C /* FLEView.m in Sources */,
-				33A87EB720F6BCDB0086D21D /* FLECodecs.m in Sources */,
+				33A87EB720F6BCDB0086D21D /* FLEJSONMethodCodec.m in Sources */,
 				AA8AE8BA1FD948BA00B6FB31 /* FLETextInputModel.m in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;