diff --git a/.verchew.ini b/.verchew.ini
index f8ee11b..6d60652 100644
--- a/.verchew.ini
+++ b/.verchew.ini
@@ -26,6 +26,13 @@ version = 2
 optional = true
 message = $ brew install graphviz
 
+[resize]
+
+cli = /usr/X11/bin/resize
+version = Usage: resize
+optional = true
+message = $ brew install --cask xquartz
+
 [asciinema]
 
 cli = asciinema
diff --git a/Makefile b/Makefile
index 2784ebc..4f46de2 100644
--- a/Makefile
+++ b/Makefile
@@ -171,7 +171,7 @@ docs/*.png: $(MODULES)
 docs/demo.gif: docs/demo.cast
 	asciicast2gif $< $@
 docs/demo.cast: Makefile
-	resize -s 61 127
+	/usr/X11/bin/resize -s 61 127
 	poetry run asciinema rec $@ --overwrite --command "make demo CI=true RECORDING_DELAY=1" --title "GitMan Demo"
 	poetry run asciinema upload $@