diff --git a/Database/AthenaRoot/RootAuxDynIO/CMakeLists.txt b/Database/AthenaRoot/RootAuxDynIO/CMakeLists.txt
index c957259220e61c638cfaeebb593dce0a3eea3938..6ce99c01a124f68ed7b82727d3e63e7741d42b8c 100644
--- a/Database/AthenaRoot/RootAuxDynIO/CMakeLists.txt
+++ b/Database/AthenaRoot/RootAuxDynIO/CMakeLists.txt
@@ -1,4 +1,4 @@
-# Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration
+# Copyright (C) 2002-2024 CERN for the benefit of the ATLAS collaboration
 
 # Declare the package name:
 atlas_subdir( RootAuxDynIO )
@@ -16,3 +16,8 @@ atlas_add_library( RootAuxDynIO
                    PRIVATE_LINK_LIBRARIES ${ROOT_LIBRARIES}
                      AthContainers AthContainersInterfaces AthContainersRoot  RootUtils
                    )
+
+atlas_add_library( RootAuxDynIOHeaders
+                   RootAuxDynIO/RootAuxDynDefs.h
+                   INTERFACE
+                   PUBLIC_HEADERS RootAuxDynIO )
diff --git a/Database/AthenaRoot/RootAuxDynIO/RootAuxDynIO/RootAuxDynDefs.h b/Database/AthenaRoot/RootAuxDynIO/RootAuxDynIO/RootAuxDynDefs.h
index 76da581a724e265a6b9e251524aaf6943087c4b4..0876544c1cda201efc875cc36508363e5fd022a6 100644
--- a/Database/AthenaRoot/RootAuxDynIO/RootAuxDynIO/RootAuxDynDefs.h
+++ b/Database/AthenaRoot/RootAuxDynIO/RootAuxDynIO/RootAuxDynDefs.h
@@ -1,11 +1,9 @@
 /*
   Copyright (C) 2002-2024 CERN for the benefit of the ATLAS collaboration
 */
-
 #ifndef ROOTAUXDYN_DEFS_H
 #define ROOTAUXDYN_DEFS_H
 
-
 namespace RootAuxDynIO
 {
    /// Common post-fix for the names of auxiliary containers in StoreGate
@@ -14,11 +12,11 @@ namespace RootAuxDynIO
    constexpr char   AUXDYN_POSTFIX[] = "Dyn.";
    constexpr size_t AUXDYN_POSTFIX_LEN = sizeof(AUXDYN_POSTFIX)-1;
 
-   /// check if a string ends with AUX_POSTFIX
-   inline bool endsWithAuxPostfix(std::string_view str) {
-      return str.size() >= AUX_POSTFIX_LEN and
-         str.compare(str.size()-AUX_POSTFIX_LEN, AUX_POSTFIX_LEN, AUX_POSTFIX) == 0;
-   }
+   /**
+   * @brief Check if a string ends with AUX_POSTFIX
+   * @param str the string to check
+   */
+   bool endsWithAuxPostfix(std::string_view str);
 
    /**
    * @brief Construct branch name for a given dynamic attribute
@@ -37,6 +35,13 @@ namespace RootAuxDynIO
 } // namespace
 
 
+/// check if a string ends with AUX_POSTFIX
+inline bool
+RootAuxDynIO::endsWithAuxPostfix(std::string_view str) {
+   return str.size() >= AUX_POSTFIX_LEN and
+      str.compare(str.size()-AUX_POSTFIX_LEN, AUX_POSTFIX_LEN, AUX_POSTFIX) == 0;
+}
+
 inline std::string
 RootAuxDynIO::auxBranchName(const std::string& attr_name, const std::string& baseBranchName)
 {
@@ -55,7 +60,4 @@ RootAuxDynIO::auxFieldName(const std::string& attr_name, const std::string& base
    return field_name;
 }
 
-
-
-
 #endif