diff --git a/jpyinterpreter/pom.xml b/jpyinterpreter/pom.xml
index a285ca5..5b6bcca 100644
--- a/jpyinterpreter/pom.xml
+++ b/jpyinterpreter/pom.xml
@@ -4,7 +4,7 @@
   <parent>
     <groupId>ai.timefold.solver</groupId>
     <artifactId>timefold-solver-python-parent</artifactId>
-    <version>1.12.0</version>
+    <version>999-SNAPSHOT</version>
     <relativePath>../pom.xml</relativePath>
   </parent>
   <modelVersion>4.0.0</modelVersion>
diff --git a/pom.xml b/pom.xml
index ecc344b..e4ea042 100644
--- a/pom.xml
+++ b/pom.xml
@@ -4,7 +4,7 @@
   <parent>
     <groupId>ai.timefold.solver</groupId>
     <artifactId>timefold-solver-build-parent</artifactId>
-    <version>1.12.0</version>
+    <version>999-SNAPSHOT</version>
   </parent>
 
   <modelVersion>4.0.0</modelVersion>
diff --git a/setup.py b/setup.py
index 4e4c5cd..e9087d7 100644
--- a/setup.py
+++ b/setup.py
@@ -117,7 +117,7 @@ def find_stub_files(stub_root: str):
 
 this_directory = Path(__file__).parent
 long_description = (this_directory / "README.md").read_text()
-timefold_solver_python_version = '1.12.0b0'
+timefold_solver_python_version = '999-dev0'
 
 setup(
     name='timefold',
diff --git a/timefold-solver-python-core/pom.xml b/timefold-solver-python-core/pom.xml
index 68563c3..977e305 100644
--- a/timefold-solver-python-core/pom.xml
+++ b/timefold-solver-python-core/pom.xml
@@ -4,7 +4,7 @@
   <parent>
     <groupId>ai.timefold.solver</groupId>
     <artifactId>timefold-solver-python-parent</artifactId>
-    <version>1.12.0</version>
+    <version>999-SNAPSHOT</version>
     <relativePath>../pom.xml</relativePath>
   </parent>
   <modelVersion>4.0.0</modelVersion>