--- setup.py.orig	2015-12-01 07:03:03.000000000 -0800
+++ setup.py	2019-02-17 11:24:54.000000000 -0800
@@ -40,6 +40,7 @@
 # Unixoid OS's I will just look for the usual suspects.
 
 libdirs = dirtest([
+    "PREFIX",
     "/usr/local/lib", "/sw/lib", "/usr/lib",
     "/usr/lib/i386-linux-gnu", "/usr/lib/x86_64-linux-gnu",
     "/usr/lib/X11", "/usr/X11R6/lib",
@@ -55,6 +56,7 @@
 # include_dirs are also non-portable; same trick here.
 
 incdirs = dirtest([
+    "PREFIX",
     "/usr/local/include", "/sw/include", "/usr/include",
     "/usr/include/X11", "/usr/X11R6/include",
     "/opt/gnome/include",