diff --git a/doc/INSTALL.md b/doc/INSTALL.md
index 8fb983857..d5555fb28 100644
--- a/doc/INSTALL.md
+++ b/doc/INSTALL.md
@@ -70,7 +70,7 @@ If you can't install `lowdown`, a version will be built in-tree.
 
 If you want to build the Rust plugins (currently, cln-grpc):
 
-	sudo apt-get install -y cargo rustfmt
+	sudo apt-get install -y cargo rustfmt protobuf-compiler
 
 There are two ways to build core lightning, and this depends on how you want use it.