diff --git a/.github/workflows/format.yml b/.github/workflows/format.yml
index e7ec956..b3f4bcd 100644
--- a/.github/workflows/format.yml
+++ b/.github/workflows/format.yml
@@ -19,7 +19,7 @@ jobs:
           sudo apt-get -y install python3 python3-pip
 
           # fix version here for now
-          pip3 install --break-system-packages clang-format==18.1.5
+          pip3 install --break-system-packages clang-format==19.1.0
 
       - name: run-clang-format
         run: |
diff --git a/async/as/Base.h b/async/as/Base.h
index 7239169..d7ffac1 100644
--- a/async/as/Base.h
+++ b/async/as/Base.h
@@ -97,8 +97,8 @@ class Base : public async::ExecInfo {
    * @param clone True of the buffer is the same (a clone) on all MPI processes.
    *  (Allows additional optimizations.)
    */
-  virtual auto
-      addSyncBuffer(const void* buffer, size_t size, bool clone = false) -> unsigned int = 0;
+  virtual auto addSyncBuffer(const void* buffer, size_t size, bool clone = false)
+      -> unsigned int = 0;
 
   /**
    * @param buffer The original memory location in the application or NULL if ASYNC should
diff --git a/async/as/MPIBase.h b/async/as/MPIBase.h
index fbd2936..7c4bbfe 100644
--- a/async/as/MPIBase.h
+++ b/async/as/MPIBase.h
@@ -185,8 +185,8 @@ class MPIBase : public ThreadBase<Executor, InitParameter, Parameter>, private S
 
   [[nodiscard]] auto scheduler() const -> const MPIScheduler& { return *m_scheduler; }
 
-  auto
-      addBuffer(const void* buffer, size_t size, bool clone = false, bool sync = true) -> unsigned {
+  auto addBuffer(const void* buffer, size_t size, bool clone = false, bool sync = true)
+      -> unsigned {
     assert(m_scheduler);
     assert(!m_scheduler->isExecutor());