diff --git a/src/blackboard.cpp b/src/blackboard.cpp
index ba6a516ad..667ba1440 100644
--- a/src/blackboard.cpp
+++ b/src/blackboard.cpp
@@ -44,7 +44,7 @@ const PortInfo* Blackboard::portInfo(const std::string &key)
 
 void Blackboard::addSubtreeRemapping(StringView internal, StringView external)
 {
-    internal_to_external_.insert( {internal.to_string(), external.to_string()} );
+    internal_to_external_.insert( {static_cast<std::string>(internal), static_cast<std::string>(external)} );
 }
 
 void Blackboard::debugMessage() const
diff --git a/src/bt_factory.cpp b/src/bt_factory.cpp
index 4c6764fe7..76e47e877 100644
--- a/src/bt_factory.cpp
+++ b/src/bt_factory.cpp
@@ -168,7 +168,7 @@ std::vector<std::string> getCatkinLibraryPaths()
             splitString(env_catkin_prefix_paths, os_pathsep);
         for (BT::StringView catkin_prefix_path : catkin_prefix_paths)
         {
-            filesystem::path path(catkin_prefix_path.to_string());
+            filesystem::path path(static_cast<std::string>(catkin_prefix_path));
             filesystem::path lib("lib");
             lib_paths.push_back((path / lib).str());
         }