diff --git a/pom.xml b/pom.xml
index dd356edb..a571fe31 100644
--- a/pom.xml
+++ b/pom.xml
@@ -29,7 +29,7 @@
   <parent>
     <groupId>org.jenkins-ci.plugins</groupId>
     <artifactId>plugin</artifactId>
-    <version>3.43</version>
+    <version>4.1</version>
     <relativePath />
   </parent>
 
@@ -67,10 +67,8 @@
   <properties>
     <revision>2.5.7</revision>
     <changelist>-SNAPSHOT</changelist>
-    <jenkins.version>2.138.4</jenkins.version>
+    <jenkins.version>2.176.4</jenkins.version>
     <java.level>8</java.level>
-    <scm-api.version>2.4.1</scm-api.version>
-    <git-plugin.version>3.10.0</git-plugin.version>
   </properties>
 
   <repositories>
@@ -87,83 +85,59 @@
     </pluginRepository>
   </pluginRepositories>
 
+  <dependencyManagement>
+    <dependencies>
+      <dependency>
+        <groupId>io.jenkins.tools.bom</groupId>
+        <artifactId>bom-2.176.x</artifactId>
+        <version>9</version>
+        <scope>import</scope>
+        <type>pom</type>
+      </dependency>
+    </dependencies>
+  </dependencyManagement>
+
   <dependencies>
     <!-- plugin dependencies -->
     <dependency>
       <groupId>org.jenkins-ci.plugins</groupId>
       <artifactId>scm-api</artifactId>
-      <version>${scm-api.version}</version>
     </dependency>
     <dependency>
       <groupId>org.jenkins-ci.plugins</groupId>
       <artifactId>cloudbees-folder</artifactId>
-      <version>6.11</version>
     </dependency>
-    <dependency>
-      <groupId>org.jenkins-ci.plugins</groupId>
-      <artifactId>structs</artifactId>
-      <version>1.18</version>
-    </dependency>
-    <!-- jenkins dependencies -->
     <!-- test dependencies -->
     <dependency>
       <groupId>org.mockito</groupId>
       <artifactId>mockito-core</artifactId>
-      <version>1.8.5</version>
-      <scope>test</scope>
-      <exclusions>
-        <exclusion>
-          <groupId>org.hamcrest</groupId>
-          <artifactId>hamcrest-core</artifactId>
-        </exclusion>
-      </exclusions>
-    </dependency>
-    <dependency> <!-- previously gathered from org.jenkins-ci.lib:lib-jenkins-maven-embedder -->
-      <groupId>org.codehaus.plexus</groupId>
-      <artifactId>plexus-utils</artifactId>
-      <version>2.1</version>
       <scope>test</scope>
     </dependency>
     <dependency>
       <groupId>org.jenkins-ci.plugins</groupId>
       <artifactId>scm-api</artifactId>
-      <version>${scm-api.version}</version>
       <classifier>tests</classifier>
       <scope>test</scope>
     </dependency>
     <dependency>
       <groupId>org.jenkins-ci.plugins</groupId>
       <artifactId>credentials</artifactId>
-      <version>2.1.16</version>
       <scope>test</scope>
     </dependency>
     <dependency>
       <groupId>org.jenkins-ci.plugins</groupId>
       <artifactId>git</artifactId>
-      <version>${git-plugin.version}</version>
       <scope>test</scope>
-      <exclusions>
-        <exclusion>
-          <groupId>org.apache.httpcomponents</groupId>
-          <artifactId>httpcore</artifactId>
-        </exclusion>
-        <exclusion>
-          <groupId>org.apache.httpcomponents</groupId>
-          <artifactId>httpclient</artifactId>
-        </exclusion>
-      </exclusions>
     </dependency>
     <dependency>
       <groupId>org.jenkins-ci.plugins</groupId>
       <artifactId>git</artifactId>
-      <version>${git-plugin.version}</version>
       <classifier>tests</classifier>
       <scope>test</scope>
     </dependency>
     <dependency>
       <groupId>org.jenkins-ci.plugins</groupId>
       <artifactId>junit</artifactId>
-      <version>1.6</version>
       <scope>test</scope>
     </dependency>
   </dependencies>
@@ -177,6 +151,13 @@
           <compatibleSinceVersion>2.0.0</compatibleSinceVersion>
         </configuration>
       </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <configuration>
+          <reuseForks>false</reuseForks> <!-- TODO reuse seems to cause problems with GitSampleRepoRule -->
+        </configuration>
+      </plugin>
     </plugins>
   </build>
 
diff --git a/src/main/java/jenkins/branch/BuildRetentionBranchProperty.java b/src/main/java/jenkins/branch/BuildRetentionBranchProperty.java
index 9be6f511..b4ea15af 100644
--- a/src/main/java/jenkins/branch/BuildRetentionBranchProperty.java
+++ b/src/main/java/jenkins/branch/BuildRetentionBranchProperty.java
@@ -6,6 +6,7 @@
 import hudson.model.Job;
 import hudson.model.Run;
 import jenkins.model.BuildDiscarder;
+import org.jenkinsci.Symbol;
 import org.kohsuke.stapler.DataBoundConstructor;
 
 import java.io.IOException;
@@ -84,6 +85,7 @@ public Boolean run() {
     /**
      * Our {@link hudson.model.Descriptor}.
      */
+    @Symbol("buildRetention")
     @Extension
     @SuppressWarnings("unused") // instantiated by Jenkins
     public static class DescriptorImpl extends BranchPropertyDescriptor {
diff --git a/src/main/java/jenkins/branch/DefaultBranchPropertyStrategy.java b/src/main/java/jenkins/branch/DefaultBranchPropertyStrategy.java
index 3a87cf05..d69ab12a 100644
--- a/src/main/java/jenkins/branch/DefaultBranchPropertyStrategy.java
+++ b/src/main/java/jenkins/branch/DefaultBranchPropertyStrategy.java
@@ -27,6 +27,7 @@
 import edu.umd.cs.findbugs.annotations.NonNull;
 import hudson.Extension;
 import jenkins.scm.api.SCMHead;
+import org.jenkinsci.Symbol;
 import org.kohsuke.stapler.DataBoundConstructor;
 
 import java.util.ArrayList;
@@ -81,6 +82,7 @@ public List<BranchProperty> getPropertiesFor(SCMHead head) {
     /**
      * Our {@link BranchPropertyStrategyDescriptor}.
      */
+    @Symbol("allBranchesSame")
     @Extension
     @SuppressWarnings("unused") // by jenkins
     public static class DescriptorImpl extends BranchPropertyStrategyDescriptor {
diff --git a/src/main/java/jenkins/branch/NamedExceptionsBranchPropertyStrategy.java b/src/main/java/jenkins/branch/NamedExceptionsBranchPropertyStrategy.java
index 674f75b1..91587479 100644
--- a/src/main/java/jenkins/branch/NamedExceptionsBranchPropertyStrategy.java
+++ b/src/main/java/jenkins/branch/NamedExceptionsBranchPropertyStrategy.java
@@ -32,6 +32,7 @@
 import jenkins.scm.api.SCMHead;
 import org.apache.commons.lang.StringUtils;
 import org.apache.tools.ant.types.selectors.SelectorUtils;
+import org.jenkinsci.Symbol;
 import org.kohsuke.stapler.DataBoundConstructor;
 
 import java.io.File;
@@ -112,6 +113,7 @@ public List<BranchProperty> getPropertiesFor(SCMHead head) {
     /**
      * Our {@link BranchPropertyStrategyDescriptor}.
      */
+    @Symbol("namedBranchesDifferent")
     @Extension
     @SuppressWarnings("unused") // by jenkins
     public static class DescriptorImpl extends BranchPropertyStrategyDescriptor {
diff --git a/src/main/java/jenkins/branch/NoTriggerBranchProperty.java b/src/main/java/jenkins/branch/NoTriggerBranchProperty.java
index 91dac18c..cdd98ee2 100644
--- a/src/main/java/jenkins/branch/NoTriggerBranchProperty.java
+++ b/src/main/java/jenkins/branch/NoTriggerBranchProperty.java
@@ -32,6 +32,7 @@
 import hudson.model.Queue;
 import hudson.model.Run;
 import java.util.List;
+import org.jenkinsci.Symbol;
 import org.kohsuke.accmod.Restricted;
 import org.kohsuke.accmod.restrictions.NoExternalUse;
 import org.kohsuke.stapler.DataBoundConstructor;
@@ -52,6 +53,7 @@ public <P extends Job<P, B>, B extends Run<P, B>> JobDecorator<P, B> jobDecorato
         return null;
     }
 
+    @Symbol("suppressAutomaticTriggering")
     @Extension
     public static class DescriptorImpl extends BranchPropertyDescriptor {
         @Override
diff --git a/src/main/java/jenkins/branch/RateLimitBranchProperty.java b/src/main/java/jenkins/branch/RateLimitBranchProperty.java
index a9c1cc14..d689ebc0 100644
--- a/src/main/java/jenkins/branch/RateLimitBranchProperty.java
+++ b/src/main/java/jenkins/branch/RateLimitBranchProperty.java
@@ -181,6 +181,7 @@ public List<JobProperty<? super P>> jobProperties(
     /**
      * Our descriptor
      */
+    @Symbol("rateLimit")
     @Extension
     @SuppressWarnings("unused") // instantiated by jenkins
     public static class DescriptorImpl extends BranchPropertyDescriptor {
diff --git a/src/main/java/jenkins/branch/UntrustedBranchProperty.java b/src/main/java/jenkins/branch/UntrustedBranchProperty.java
index 73fa03f6..4ec0da15 100644
--- a/src/main/java/jenkins/branch/UntrustedBranchProperty.java
+++ b/src/main/java/jenkins/branch/UntrustedBranchProperty.java
@@ -33,6 +33,7 @@
 import hudson.tasks.BuildWrapper;
 import hudson.tasks.Publisher;
 import java.lang.reflect.Type;
+import org.jenkinsci.Symbol;
 import org.kohsuke.stapler.DataBoundConstructor;
 
 import java.util.ArrayList;
@@ -120,6 +121,7 @@ public <P extends Job<P,B>,B extends Run<P,B>> JobDecorator<P,B> jobDecorator(Cl
     /**
      * Our {@link Descriptor}.
      */
+    @Symbol("untrusted")
     @Extension
     @SuppressWarnings("unused") // instantiated by Jenkins
     public static class DescriptorImpl extends BranchPropertyDescriptor {
diff --git a/src/test/java/jenkins/branch/BranchCategoryFilterTest.java b/src/test/java/jenkins/branch/BranchCategoryFilterTest.java
index 3e7e9ed2..80379710 100644
--- a/src/test/java/jenkins/branch/BranchCategoryFilterTest.java
+++ b/src/test/java/jenkins/branch/BranchCategoryFilterTest.java
@@ -147,21 +147,21 @@ public void filter_specificCategory() throws Exception {
 
     }
 
-    private static abstract class TopLevelJob extends Job<TopLevelJob, TopLevelRun> implements TopLevelItem {
+    public static abstract class TopLevelJob extends Job<TopLevelJob, TopLevelRun> implements TopLevelItem {
 
         protected TopLevelJob(ItemGroup parent, String name) {
             super(parent, name);
         }
     }
 
-    private static abstract class TopLevelRun extends Run<TopLevelJob, TopLevelRun> {
+    public static abstract class TopLevelRun extends Run<TopLevelJob, TopLevelRun> {
 
         protected TopLevelRun(@Nonnull TopLevelJob job) throws IOException {
             super(job);
         }
     }
 
-    private static abstract class MockSCMSource extends SCMSource {
+    public static abstract class MockSCMSource extends SCMSource {
 
         protected MockSCMSource() {
             super("1");