diff --git a/rebar.config b/rebar.config
index 857a9a9..b4d28cd 100644
--- a/rebar.config
+++ b/rebar.config
@@ -3,6 +3,10 @@
 {erl_opts, [debug_info]}.
 {deps, []}.
 
+%% Prevent build directories being used in output files
+{xrl_opts, [{deterministic, true}]}.
+{yrl_opts, [{deterministic, true}]}.
+
 {shell, [
   % {config, "config/sys.config"},
     {apps, [luerl]}