/usr/include/caf/detail/ is in libcaf-dev 0.13.2-3.
This file is owned by root:root, with mode 0o755.
..
/usr/include/caf/detail/abstract_uniform_type_info.hpp
/usr/include/caf/detail/actor_registry.hpp
/usr/include/caf/detail/apply_args.hpp
/usr/include/caf/detail/arg_match_t.hpp
/usr/include/caf/detail/atom_val.hpp
/usr/include/caf/detail/behavior_impl.hpp
/usr/include/caf/detail/behavior_stack.hpp
/usr/include/caf/detail/boxed.hpp
/usr/include/caf/detail/cas_weak.hpp
/usr/include/caf/detail/comparable.hpp
/usr/include/caf/detail/concatenated_tuple.hpp
/usr/include/caf/detail/ctm.hpp
/usr/include/caf/detail/decorated_tuple.hpp
/usr/include/caf/detail/default_uniform_type_info.hpp
/usr/include/caf/detail/disablable_delete.hpp
/usr/include/caf/detail/disposer.hpp
/usr/include/caf/detail/double_ended_queue.hpp
/usr/include/caf/detail/embedded.hpp
/usr/include/caf/detail/functor_attachable.hpp
/usr/include/caf/detail/get_mac_addresses.hpp
/usr/include/caf/detail/get_root_uuid.hpp
/usr/include/caf/detail/group_manager.hpp
/usr/include/caf/detail/ieee_754.hpp
/usr/include/caf/detail/implicit_conversions.hpp
/usr/include/caf/detail/int_list.hpp
/usr/include/caf/detail/intrusive_partitioned_list.hpp
/usr/include/caf/detail/left_or_right.hpp
/usr/include/caf/detail/limited_vector.hpp
/usr/include/caf/detail/logging.hpp
/usr/include/caf/detail/memory.hpp
/usr/include/caf/detail/memory_cache_flag_type.hpp
/usr/include/caf/detail/message_case_builder.hpp
/usr/include/caf/detail/message_data.hpp
/usr/include/caf/detail/optional_message_visitor.hpp
/usr/include/caf/detail/pair_storage.hpp
/usr/include/caf/detail/pseudo_tuple.hpp
/usr/include/caf/detail/purge_refs.hpp
/usr/include/caf/detail/raw_access.hpp
/usr/include/caf/detail/ripemd_160.hpp
/usr/include/caf/detail/safe_equal.hpp
/usr/include/caf/detail/scope_guard.hpp
/usr/include/caf/detail/shared_spinlock.hpp
/usr/include/caf/detail/single_reader_queue.hpp
/usr/include/caf/detail/singleton_mixin.hpp
/usr/include/caf/detail/singletons.hpp
/usr/include/caf/detail/split_join.hpp
/usr/include/caf/detail/sync_request_bouncer.hpp
/usr/include/caf/detail/tail_argument_token.hpp
/usr/include/caf/detail/tbind.hpp
/usr/include/caf/detail/try_match.hpp
/usr/include/caf/detail/tuple_vals.hpp
/usr/include/caf/detail/tuple_zip.hpp
/usr/include/caf/detail/type_list.hpp
/usr/include/caf/detail/type_nr.hpp
/usr/include/caf/detail/type_pair.hpp
/usr/include/caf/detail/type_traits.hpp
/usr/include/caf/detail/typed_actor_util.hpp
/usr/include/caf/detail/unboxed.hpp
/usr/include/caf/detail/uniform_type_info_map.hpp
/usr/include/caf/detail/variant_data.hpp
/usr/include/caf/detail/wrapped.hpp