diff --git a/.requirements/ghc/darwin b/.requirements/ghc/darwin
new file mode 100644
index 0000000..4c3dd9b
--- /dev/null
+++ b/.requirements/ghc/darwin
@@ -0,0 +1 @@
+(Note: on OS X, in the course of running ghcup you will be given a dialog box to install the command line tools. Accept and the requirements will be installed for you. You will then need to run the command again.)
\ No newline at end of file