diff --git a/src/engine.h b/src/engine.h
index 39b16d19df231559898622b65d0a21da427d8d23..65cb7f22a715d01c745268948c796db3a1f735ab 100644
--- a/src/engine.h
+++ b/src/engine.h
@@ -98,16 +98,6 @@ enum engine_step_properties {
 #define engine_default_timesteps_file_name "timesteps"
 #define engine_max_parts_per_ghost 1000
 
-/* MPI task tags. */
-enum engine_task_tags {
-  engine_task_tag_xv = 0,
-  engine_task_tag_rho,
-  engine_task_tag_ti,
-  engine_task_tag_grad,
-  engine_task_tag_grav,
-  engine_tasks_per_tag
-};
-
 /**
  * @brief The rank of the engine as a global variable (for messages).
  */