diff --git a/stack.yaml b/stack.yaml
new file mode 100644
index 0000000..e26b4db
--- /dev/null
+++ b/stack.yaml
@@ -0,0 +1,7 @@
+resolver: lts-12.1
+
+packages:
+    - '.'
+
+extra-deps:
+    - IfElse-0.85