diff --git a/core-groovy-2/README.md b/core-groovy-2/README.md
index 9701976142..f60bdb3cbe 100644
--- a/core-groovy-2/README.md
+++ b/core-groovy-2/README.md
@@ -2,4 +2,6 @@
 
 ## Relevant articles:
 
-- [String Matching in Groovy](http://www.baeldung.com/)
\ No newline at end of file
+- [String Matching in Groovy](http://www.baeldung.com/)
+- [Groovy def Keyword]
+
diff --git a/core-groovy-2/pom.xml b/core-groovy-2/pom.xml
index eb82f5d2e3..77de9c8fc8 100644
--- a/core-groovy-2/pom.xml
+++ b/core-groovy-2/pom.xml
@@ -14,12 +14,33 @@
     </parent>
 
     <dependencies>
+        <dependency>
+            <groupId>org.codehaus.groovy</groupId>
+            <artifactId>groovy</artifactId>
+            <version>${groovy.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.codehaus.groovy</groupId>
             <artifactId>groovy-all</artifactId>
             <version>${groovy-all.version}</version>
             <type>pom</type>
         </dependency>
+        <dependency>
+            <groupId>org.codehaus.groovy</groupId>
+            <artifactId>groovy-dateutil</artifactId>
+            <version>${groovy.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.codehaus.groovy</groupId>
+            <artifactId>groovy-sql</artifactId>
+            <version>${groovy-sql.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.platform</groupId>
+            <artifactId>junit-platform-runner</artifactId>
+            <version>${junit.platform.version}</version>
+            <scope>test</scope>
+        </dependency>
         <dependency>
             <groupId>org.hsqldb</groupId>
             <artifactId>hsqldb</artifactId>
@@ -43,12 +64,39 @@
                 <executions>
                     <execution>
                         <goals>
+                            <goal>addSources</goal>
+                            <goal>addTestSources</goal>
                             <goal>compile</goal>
                             <goal>compileTests</goal>
                         </goals>
                     </execution>
                 </executions>
             </plugin>
+            <plugin>
+                <artifactId>maven-failsafe-plugin</artifactId>
+                <version>${maven-failsafe-plugin.version}</version>
+                <dependencies>
+                    <dependency>
+                        <groupId>org.junit.platform</groupId>
+                        <artifactId>junit-platform-surefire-provider</artifactId>
+                        <version>${junit.platform.version}</version>
+                    </dependency>
+                </dependencies>
+                <executions>
+                    <execution>
+                        <id>junit5</id>
+                        <goals>
+                            <goal>integration-test</goal>
+                            <goal>verify</goal>
+                        </goals>
+                        <configuration>
+                            <includes>
+                                <include>**/*Test5.java</include>
+                            </includes>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
             <plugin>
                 <artifactId>maven-surefire-plugin</artifactId>
                 <version>2.20.1</version>
@@ -71,10 +119,13 @@
     </repositories>
 
     <properties>
+        <junit.platform.version>1.0.0</junit.platform.version>
+        <groovy.version>2.5.6</groovy.version>
         <groovy-all.version>2.5.6</groovy-all.version>
+        <groovy-sql.version>2.5.6</groovy-sql.version>
         <hsqldb.version>2.4.0</hsqldb.version>
-        <spock-core.version>1.3-groovy-2.5</spock-core.version>
-        <gmavenplus-plugin.version>1.6.3</gmavenplus-plugin.version>
+        <spock-core.version>1.1-groovy-2.4</spock-core.version>
+        <gmavenplus-plugin.version>1.6</gmavenplus-plugin.version>
     </properties>
 </project>
 
diff --git a/core-groovy-2/src/test/groovy/com/baeldung/defkeyword/DefUnitTest.groovy b/core-groovy-2/src/test/groovy/com/baeldung/defkeyword/DefUnitTest.groovy
new file mode 100644
index 0000000000..310d97d3fd
--- /dev/null
+++ b/core-groovy-2/src/test/groovy/com/baeldung/defkeyword/DefUnitTest.groovy
@@ -0,0 +1,79 @@
+package com.baeldung.defkeyword
+
+import org.codehaus.groovy.runtime.NullObject
+import org.codehaus.groovy.runtime.typehandling.GroovyCastException
+
+import groovy.transform.TypeChecked
+import groovy.transform.TypeCheckingMode
+
+@TypeChecked
+class DefUnitTest extends GroovyTestCase {
+    
+    def id
+    def firstName = "Samwell"
+    def listOfCountries = ['USA', 'UK', 'FRANCE', 'INDIA']
+    
+    @TypeChecked(TypeCheckingMode.SKIP)
+    def multiply(x, y) {
+        return x*y
+    }
+        
+    @TypeChecked(TypeCheckingMode.SKIP)
+    void testDefVariableDeclaration() {
+        
+        def list
+        assert list.getClass() == org.codehaus.groovy.runtime.NullObject
+        assert list.is(null)
+        
+        list = [1,2,4]
+        assert list instanceof ArrayList
+    }
+    
+    @TypeChecked(TypeCheckingMode.SKIP)
+    void testTypeVariables() {   
+        int rate = 200
+        try {
+            rate = [12] //GroovyCastException
+            rate = "nill" //GroovyCastException
+        } catch(GroovyCastException) {
+            println "Cannot assign anything other than integer"
+        }
+    }
+     
+    @TypeChecked(TypeCheckingMode.SKIP)
+    void testDefVariableMultipleAssignment() {
+        def rate
+        assert rate == null
+        assert rate.getClass() == org.codehaus.groovy.runtime.NullObject
+        
+        rate = 12
+        assert rate instanceof Integer
+        
+        rate = "Not Available"
+        assert rate instanceof String
+        
+        rate = [1, 4]
+        assert rate instanceof List
+        
+        assert divide(12, 3) instanceof BigDecimal
+        assert divide(1, 0) instanceof String
+
+    }
+    
+    def divide(int x, int y) {
+        if(y==0) {
+            return "Should not divide by 0"
+        } else {
+            return x/y
+        }
+    }
+    
+    def greetMsg() {
+        println "Hello! I am Groovy"
+    }
+    
+    void testDefVsType() {
+        def int count
+        assert count instanceof Integer
+    }
+}
\ No newline at end of file
diff --git a/pom.xml b/pom.xml
index 2e31200652..0de4a36336 100644
--- a/pom.xml
+++ b/pom.xml
@@ -376,7 +376,7 @@
                 <module>cdi</module>
                 <module>checker-plugin</module>
                 <module>core-groovy</module>
-				<module>core-groovy-2</module>
+                <module>core-groovy-2</module>
                 <!-- <module>core-java-10</module> --> <!-- We haven't upgraded to java 10. Fixing in BAEL-10841 -->
                 <!-- <module>core-java-11</module> --> <!-- We haven't upgraded to java 11. Fixing in BAEL-10841 -->
                 <!-- <module>core-java-12</module> --> <!-- We haven't upgraded to java 12. Fixing in BAEL-10841 -->