diff --git a/server/requirements.txt b/server/requirements.txt
index 8fa23ab..916a1b0 100644
--- a/server/requirements.txt
+++ b/server/requirements.txt
@@ -3,5 +3,7 @@ scipy
 matplotlib
 websockets==10.4
 dpath
+pyserial
+spidev
 # web/ (the browser client) needs none of these - it's static HTML/JS
 # served straight from the stdlib's http.server, no new dependency.