diff --git a/pom.xml b/pom.xml
index 8d4dfdb4..c0a6efd1 100644
--- a/pom.xml
+++ b/pom.xml
@@ -84,7 +84,6 @@
         <!-- versions -->
         <guava.version>28.0-jre</guava.version>
         <jsr305.version>3.0.2</jsr305.version>
-        <okhttp.version>4.4.0</okhttp.version>
         <jsr311-api.version>1.1.1</jsr311-api.version>
         <junit.version>4.13</junit.version>
         <slf4j-api.version>1.7.12</slf4j-api.version>
@@ -122,12 +121,7 @@
         <dependency>
             <groupId>com.squareup.okhttp3</groupId>
             <artifactId>okhttp</artifactId>
-            <version>${okhttp.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>com.squareup.okhttp3</groupId>
-            <artifactId>mockwebserver</artifactId>
-            <version>${okhttp.version}</version>
+            <version>3.14.7</version>
         </dependency>
         <dependency>
             <groupId>org.slf4j</groupId>
@@ -211,6 +205,12 @@
             <version>${mockito-core.version}</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>com.squareup.okhttp3</groupId>
+            <artifactId>mockwebserver</artifactId>
+            <version>3.14.7</version>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>org.powermock</groupId>
             <artifactId>powermock-module-junit4</artifactId>
diff --git a/src/main/java/com/spotify/github/v3/clients/GitHubClient.java b/src/main/java/com/spotify/github/v3/clients/GitHubClient.java
index 9af0b4bd..6f16a071 100644
--- a/src/main/java/com/spotify/github/v3/clients/GitHubClient.java
+++ b/src/main/java/com/spotify/github/v3/clients/GitHubClient.java
@@ -66,15 +66,15 @@ public class GitHubClient {
 
   static final Consumer<Response> IGNORE_RESPONSE_CONSUMER = (ignore) -> {};
   static final TypeReference<List<Comment>> LIST_COMMENT_TYPE_REFERENCE =
-      new TypeReference<List<Comment>>() {};
+      new TypeReference<>() {};
   static final TypeReference<List<CommitItem>> LIST_COMMIT_TYPE_REFERENCE =
-      new TypeReference<List<CommitItem>>() {};
+      new TypeReference<>() {};
   static final TypeReference<List<Status>> LIST_STATUS_TYPE_REFERENCE =
-      new TypeReference<List<Status>>() {};
+      new TypeReference<>() {};
   static final TypeReference<List<FolderContent>> LIST_FOLDERCONTENT_TYPE_REFERENCE =
-      new TypeReference<List<FolderContent>>() {};
+      new TypeReference<>() {};
   static final TypeReference<List<PullRequestItem>> LIST_PR_TYPE_REFERENCE =
-      new TypeReference<List<PullRequestItem>>() {};
+      new TypeReference<>() {};
 
   private static final String GET_ACCESS_TOKEN_URL = "app/installations/%s/access_tokens";
 
diff --git a/src/test/java/com/spotify/github/v3/clients/GitHubAuthTest.java b/src/test/java/com/spotify/github/v3/clients/GitHubAuthTest.java
index 821ee279..71a210c7 100644
--- a/src/test/java/com/spotify/github/v3/clients/GitHubAuthTest.java
+++ b/src/test/java/com/spotify/github/v3/clients/GitHubAuthTest.java
@@ -52,7 +52,7 @@ public class GitHubAuthTest {
                       "com/spotify/github/v3/github-private-key"))
               .getFile());
   private URI url;
-  private MockWebServer mockServer = new MockWebServer();
+  private final MockWebServer mockServer = new MockWebServer();
   private OkHttpClient client;
   private ChecksClient checksClient;