diff --git a/script/setup b/script/setup
index e00ea9e8..5e10162d 100755
--- a/script/setup
+++ b/script/setup
@@ -4,7 +4,7 @@ set -eu
 
 # Change version number to a release/tag available on the mono repo to update it
 # https://github.com/appsignal/mono/releases
-MONO_VERSION="v0.5.4"
+MONO_VERSION="v0.5.5"
 
 MONO_PATH="$HOME/mono"