diff --git a/lib/src/pkce.dart b/lib/src/pkce.dart
index f2c710f7..35bae15a 100644
--- a/lib/src/pkce.dart
+++ b/lib/src/pkce.dart
@@ -64,4 +64,12 @@ class Pkce {
       );
     }
   }
+
+  /// Creates a JSON-serializable representation of this instance.
+  Map<String, dynamic> toJson() {
+    return {
+      'code_challenge': codeChallenge,
+      'code_challenge_method': codeChallengeMethod
+    };
+  }
 }
diff --git a/lib/src/server.dart b/lib/src/server.dart
index 712c74c7..c8aa690e 100644
--- a/lib/src/server.dart
+++ b/lib/src/server.dart
@@ -215,6 +215,10 @@ abstract class AuthorizationServer<Client, User> {
       state = query['state']?.toString() ?? '';
       var responseType = await _getParam(req, 'response_type', state);
 
+      req.container.registerLazySingleton<Pkce>((_) {
+        return new Pkce.fromJson(req.queryParameters, state: state);
+      });
+
       if (responseType == 'code') {
         // Ensure client ID
         // TODO: Handle confidential clients
@@ -339,6 +343,10 @@ abstract class AuthorizationServer<Client, User> {
 
       state = body['state']?.toString() ?? '';
 
+      req.container.registerLazySingleton<Pkce>((_) {
+        return new Pkce.fromJson(req.bodyAsMap, state: state);
+      });
+
       var grantType = await _getParam(req, 'grant_type', state,
           body: true, throwIfEmpty: false);