diff --git a/chapter-4/non-blocking-io/pom.xml b/chapter-4/non-blocking-io/pom.xml
index bb70da62..e44e0400 100644
--- a/chapter-4/non-blocking-io/pom.xml
+++ b/chapter-4/non-blocking-io/pom.xml
@@ -17,7 +17,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 
-        <vertx-core.version>4.4.0</vertx-core.version>
+        <vertx-core.version>4.5.2</vertx-core.version>
     </properties>
 
     <dependencies>