diff --git a/include/fmt/os.h b/include/fmt/os.h
index 58a16a57..d94075a8 100644
--- a/include/fmt/os.h
+++ b/include/fmt/os.h
@@ -379,7 +379,7 @@ struct ostream_params {
 #  endif
 };
 
-class file_buffer final : public detail::buffer<char> {
+class file_buffer final : public buffer<char> {
   file file_;
 
   FMT_API void grow(size_t) override;