diff --git a/pom.xml b/pom.xml
index 6c8fea9a..de430cce 100644
--- a/pom.xml
+++ b/pom.xml
@@ -59,8 +59,9 @@
         </repository>
     </distributionManagement>
     <properties>
-        <java.version>1.6</java.version>
-        <java.testversion>1.8</java.testversion>
+        <maven.compiler.release>11</maven.compiler.release>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <version.jackson>2.12.1</version.jackson>
         <version.slf4j>1.7.30</version.slf4j>
@@ -150,7 +151,7 @@
             <plugin>
                 <groupId>org.apache.felix</groupId>
                 <artifactId>maven-bundle-plugin</artifactId>
-                <version>4.2.1</version>
+                <version>5.1.2</version>
                 <extensions>true</extensions>
                 <configuration>
                     <instructions>
@@ -237,7 +238,6 @@
                             <goal>jar</goal>
                         </goals>
                         <configuration>
-                            <source>8</source>
                         </configuration>
                     </execution>
                 </executions>
@@ -245,12 +245,10 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
-                <version>3.6.1</version>
+                <version>3.8.1</version>
                 <configuration>
-                    <source>${java.version}</source>
-                    <target>${java.version}</target>
-                    <testSource>${java.testversion}</testSource>
-                    <testTarget>${java.testversion}</testTarget>
+                    <showDeprecation>true</showDeprecation>
+                    <showWarnings>true</showWarnings>
                 </configuration>
                 <executions>
                     <execution>
@@ -260,8 +258,6 @@
                             <goal>testCompile</goal>
                         </goals>
                         <configuration>
-                            <source>${java.testversion}</source>
-                            <target>${java.testversion}</target>
                         </configuration>
                     </execution>
                 </executions>
diff --git a/src/main/java/com/networknt/schema/NotValidator.java b/src/main/java/com/networknt/schema/NotValidator.java
index 727ce230..e1f0a81e 100644
--- a/src/main/java/com/networknt/schema/NotValidator.java
+++ b/src/main/java/com/networknt/schema/NotValidator.java
@@ -21,7 +21,6 @@
 import org.slf4j.LoggerFactory;
 
 import java.util.Collections;
-import java.util.LinkedHashSet;
 import java.util.Set;
 
 public class NotValidator extends BaseJsonValidator implements JsonValidator {
diff --git a/src/main/java/com/networknt/schema/PatternValidator.java b/src/main/java/com/networknt/schema/PatternValidator.java
index 1a156978..71d19ac6 100644
--- a/src/main/java/com/networknt/schema/PatternValidator.java
+++ b/src/main/java/com/networknt/schema/PatternValidator.java
@@ -26,7 +26,6 @@
 import org.slf4j.LoggerFactory;
 
 import java.util.Collections;
-import java.util.LinkedHashSet;
 import java.util.Set;
 import java.util.regex.Pattern;
 import java.util.regex.PatternSyntaxException;
diff --git a/src/main/java/com/networknt/schema/RefValidator.java b/src/main/java/com/networknt/schema/RefValidator.java
index 167d3799..c789f508 100644
--- a/src/main/java/com/networknt/schema/RefValidator.java
+++ b/src/main/java/com/networknt/schema/RefValidator.java
@@ -25,8 +25,6 @@
 import java.net.URI;
 import java.text.MessageFormat;
 import java.util.Collections;
-import java.util.HashSet;
-import java.util.LinkedHashSet;
 import java.util.Set;
 
 public class RefValidator extends BaseJsonValidator implements JsonValidator {
diff --git a/src/main/java/com/networknt/schema/walk/WalkEvent.java b/src/main/java/com/networknt/schema/walk/WalkEvent.java
index cd950d6a..a477864c 100644
--- a/src/main/java/com/networknt/schema/walk/WalkEvent.java
+++ b/src/main/java/com/networknt/schema/walk/WalkEvent.java
@@ -58,7 +58,7 @@ public JsonSchemaFactory getCurrentJsonSchemaFactory() {
 		return currentJsonSchemaFactory;
 	}
 
-	static class WalkEventBuilder {
+	public static class WalkEventBuilder {
 		private WalkEvent keywordWalkEvent = null;
 
 		WalkEventBuilder() {
diff --git a/src/main/java/module-info.java b/src/main/java/module-info.java
new file mode 100644
index 00000000..c54d699e
--- /dev/null
+++ b/src/main/java/module-info.java
@@ -0,0 +1,15 @@
+module com.networknt.schema {
+    requires org.apache.commons.lang3;
+    requires org.jruby.jcodings;
+    requires org.jruby.joni;
+    requires org.slf4j;
+    requires transitive com.fasterxml.jackson.databind;
+
+    opens com.networknt.schema to com.fasterxml.jackson.databind;
+
+    exports com.networknt.schema;
+    exports com.networknt.schema.format;
+    exports com.networknt.schema.uri;
+    exports com.networknt.schema.urn;
+    exports com.networknt.schema.walk;
+}