diff --git a/Set-up-Build-Environment-on-OS-X.md b/Set-up-Build-Environment-on-OS-X.md
index ec7177d..70cd229 100644
--- a/Set-up-Build-Environment-on-OS-X.md
+++ b/Set-up-Build-Environment-on-OS-X.md
@@ -24,7 +24,15 @@ Then install the required libraries (zlib already exists on macOS Sierra so it i
 Open a Terminal:
 
 ```
-brew install qt5 libgcrypt argon2 libyubikey ykpers qrencode libsodium
+brew install qt5 libgcrypt argon2 qrencode libsodium
+```
+
+### Install optional dependencies
+
+These dependencies are only needed if you build with -DWITH_XC_ALL=ON or the specific option you are building:
+
+```
+brew install libyubikey ykpers
 ```
 
 ### Update your environment regularly