diff --git a/.github/workflows/nightly.yml b/.github/workflows/nightly.yml
index 01811e648..590571e00 100644
--- a/.github/workflows/nightly.yml
+++ b/.github/workflows/nightly.yml
@@ -17,7 +17,7 @@ permissions:
 env:
   MAJOR: '4'
   MINOR: '15'
-  PATCH: '5'
+  PATCH: '6'
 
 jobs:
   # ============================================================================
diff --git a/MODULE.bazel b/MODULE.bazel
index 985a66b8e..4c13a5407 100644
--- a/MODULE.bazel
+++ b/MODULE.bazel
@@ -1,6 +1,6 @@
 module(
     name = "z3",
-    version = "4.15.5",  # TODO: Read from VERSION.txt - currently manual sync required
+    version = "4.15.6",  # TODO: Read from VERSION.txt - currently manual sync required
     bazel_compatibility = [">=7.0.0"],
 )
 
diff --git a/scripts/VERSION.txt b/scripts/VERSION.txt
index 79c398614..24b0bf345 100644
--- a/scripts/VERSION.txt
+++ b/scripts/VERSION.txt
@@ -1 +1 @@
-4.15.5.0
+4.15.6.0
diff --git a/scripts/nightly.yaml b/scripts/nightly.yaml
index 35f253b1d..3eb28e221 100644
--- a/scripts/nightly.yaml
+++ b/scripts/nightly.yaml
@@ -2,7 +2,7 @@ variables:
   # Version components read from VERSION.txt (updated manually when VERSION.txt changes)
   Major: '4'
   Minor: '15'
-  Patch: '5'
+  Patch: '6'
   ReleaseVersion: $(Major).$(Minor).$(Patch)
   NightlyVersion: $(Major).$(Minor).$(Patch).$(Build.BuildId)
   # TODO: Auto-read from VERSION.txt when Azure DevOps supports it better
diff --git a/scripts/release.yml b/scripts/release.yml
index ed072c954..ec2fc2b74 100644
--- a/scripts/release.yml
+++ b/scripts/release.yml
@@ -6,7 +6,7 @@
 trigger: none
 
 variables:
-  ReleaseVersion: '4.15.5'  # TODO: Auto-read from VERSION.txt when Azure DevOps supports it better
+  ReleaseVersion: '4.15.6'  # TODO: Auto-read from VERSION.txt when Azure DevOps supports it better
 
 stages: