diff --git a/.idea/compiler.xml b/.idea/compiler.xml
index 3ffa193..c6343a9 100644
--- a/.idea/compiler.xml
+++ b/.idea/compiler.xml
@@ -63,7 +63,7 @@
       <module name="FastDoubleParserDemo-Java8" options="-Xlint:all" />
       <module name="FastDoubleParserDemo-JavaEarlyAccess" options="-Xlint:all" />
       <module name="fastdoubleparser" options="" />
-      <module name="fastdoubleparser-dev" options="-Xlint:all" />
+      <module name="fastdoubleparser-dev" options="-Xlint:all --enable-preview" />
       <module name="fastdoubleparser-java11" options="" />
       <module name="fastdoubleparser-java17" options="" />
       <module name="fastdoubleparser-java19" options="" />
diff --git a/.idea/misc.xml b/.idea/misc.xml
index d435ca8..1134293 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -8,7 +8,7 @@
       </list>
     </option>
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_X" default="true" project-jdk-name="24" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_X" default="true" project-jdk-name="zulu-23" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>
\ No newline at end of file
diff --git a/.idea/runConfigurations/Main_Java17_canada_hex.xml b/.idea/runConfigurations/Main_Java17_canada_hex.xml
index dfbd249..1143e7b 100644
--- a/.idea/runConfigurations/Main_Java17_canada_hex.xml
+++ b/.idea/runConfigurations/Main_Java17_canada_hex.xml
@@ -4,7 +4,7 @@
     <option name="MAIN_CLASS_NAME" value="ch.randelshofer.fastdoubleparserdemo.Main" />
     <module name="fastdoubleparserdemo-dev" />
     <option name="PROGRAM_PARAMETERS" value="--markdown data/canada_hex.txt" />
-    <option name="VM_PARAMETERS" value="-XX:CompileCommand=inline,java/lang/String.charAt --enable-preview" />
+    <option name="VM_PARAMETERS" value="-XX:CompileCommand=inline,java/lang/String.charAt" />
     <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$/FastDoubleParserDemo" />
     <extension name="coverage">
       <pattern>
diff --git a/.idea/runConfigurations/Main_Java23__0_1_.xml b/.idea/runConfigurations/Main_Java23__0_1_.xml
new file mode 100644
index 0000000..79134d5
--- /dev/null
+++ b/.idea/runConfigurations/Main_Java23__0_1_.xml
@@ -0,0 +1,18 @@
+<component name="ProjectRunConfigurationManager">
+  <configuration default="false" name="Main-Java23 [0,1)" type="Application" factoryName="Application">
+    <option name="ALTERNATIVE_JRE_PATH" value="21" />
+    <option name="MAIN_CLASS_NAME" value="ch.randelshofer.fastdoubleparserdemo.Main" />
+    <module name="fastdoubleparserdemo-java23" />
+    <option name="VM_PARAMETERS" value="-XX:CompileCommand=inline,java/lang/String.charAt" />
+    <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$/FastDoubleParserDemo" />
+    <extension name="coverage">
+      <pattern>
+        <option name="PATTERN" value="ch.randelshofer.fastdoubleparser.impl.*" />
+        <option name="ENABLED" value="true" />
+      </pattern>
+    </extension>
+    <method v="2">
+      <option name="Make" enabled="true" />
+    </method>
+  </configuration>
+</component>
\ No newline at end of file
diff --git a/fastdoubleparser-dev/pom.xml b/fastdoubleparser-dev/pom.xml
index 1dcdd35..4182000 100644
--- a/fastdoubleparser-dev/pom.xml
+++ b/fastdoubleparser-dev/pom.xml
@@ -11,7 +11,7 @@
   <packaging>jar</packaging>
   <name>fastdoubleparser-dev</name>
   <properties>
-    <javaVersion>24</javaVersion>
+    <javaVersion>23</javaVersion>
     <maven.compiler.source>${javaVersion}</maven.compiler.source>
     <maven.compiler.target>${javaVersion}</maven.compiler.target>
     <maven.install.skip>true</maven.install.skip>
diff --git a/fastdoubleparserdemo-dev/pom.xml b/fastdoubleparserdemo-dev/pom.xml
index 1525716..3e45771 100644
--- a/fastdoubleparserdemo-dev/pom.xml
+++ b/fastdoubleparserdemo-dev/pom.xml
@@ -10,7 +10,7 @@
   <artifactId>fastdoubleparserdemo-dev</artifactId>
   <packaging>jar</packaging>
   <properties>
-    <javaVersion>24</javaVersion>
+    <javaVersion>23</javaVersion>
     <maven.compiler.source>${javaVersion}</maven.compiler.source>
     <maven.compiler.target>${javaVersion}</maven.compiler.target>
     <maven.install.skip>true</maven.install.skip>
diff --git a/pom.xml b/pom.xml
index 7cc9bee..043d71d 100644
--- a/pom.xml
+++ b/pom.xml
@@ -63,7 +63,7 @@
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <javaVersion>24</javaVersion>
+    <javaVersion>23</javaVersion>
     <maven.compiler.source>${javaVersion}</maven.compiler.source>
     <maven.compiler.target>${javaVersion}</maven.compiler.target>
     <!-- FIXME output timestamp does not work with Java 23, because maven-compiler-plugin 3.13.0 tries to disassemble to module-info -->