diff --git a/README.md b/README.md
index 495d805..da4e331 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,7 @@ Hardcaml is an OCaml library for designing and testing hardware designs.
 # Install
 
 ```
-$ opam install hardcaml ppx_hardcaml hardcaml_waveterm
+opam install hardcaml ppx_deriving_hardcaml hardcaml_waveterm 
 ```
 
 # Documentation