diff --git a/derivative/dlocal.py b/derivative/dlocal.py
index 011a194..b6952a1 100644
--- a/derivative/dlocal.py
+++ b/derivative/dlocal.py
@@ -35,6 +35,8 @@ def _symfd(i, x, dt, k):
         return np.sum(res)
 
     def compute(self, t, x, i):
+        import time
+        time.sleep(1e-3)
         dt = t[1] - t[0]
 
         if not self.periodic: