diff --git a/requirements.sim.txt b/requirements.sim.txt
index 9cdf037..a6c722e 100644
--- a/requirements.sim.txt
+++ b/requirements.sim.txt
@@ -4,3 +4,4 @@
 adafruit-circuitpython-midi==1.4.8
 adafruit-circuitpython-colorsys
 python-rtmidi
+websockets