diff --git a/Setup.hs b/Setup.hs
index 9a994af..4a1d95c 100644
--- a/Setup.hs
+++ b/Setup.hs
@@ -1,2 +1,17 @@
 import Distribution.Simple
-main = defaultMain
+import System.Environment
+
+-- Hacking this to work based on:
+--
+--    https://stackoverflow.com/a/39019781
+--
+-- Relies on `happy` existing at /usr/bin/happy; eg. on Arch Linux:
+--
+--    sudo pacman -S stack happy
+
+main = do
+  args <- getArgs
+  let args' = if elem "configure" args
+    then args ++ [ "--with-happy=/usr/bin/happy" ]
+    else args
+  defaultMainWithArgs args'