diff --git a/gradle.properties b/gradle.properties
index 4a0fe315d..39994fd2b 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,4 +1,4 @@
 # Warning, "version" should be the same in gradle.properties and Version.java
 # Any idea anyone how to magically synchronize those :-) ?
-version = 1.2023.12
+version = 1.2023.13beta1
 org.gradle.workers.max = 3
\ No newline at end of file
diff --git a/src/net/sourceforge/plantuml/version/Version.java b/src/net/sourceforge/plantuml/version/Version.java
index 86c31a4be..f4b8d4cd1 100644
--- a/src/net/sourceforge/plantuml/version/Version.java
+++ b/src/net/sourceforge/plantuml/version/Version.java
@@ -46,7 +46,7 @@ public class Version {
 
 	// Warning, "version" should be the same in gradle.properties and Version.java
 	// Any idea anyone how to magically synchronize those :-) ?
-	private static final String version = "1.2023.12";
+	private static final String version = "1.2023.13beta1";
 
 	public static String versionString() {
 		return version;