diff --git a/examples/acceptance_tests/057/aiken.lock b/examples/acceptance_tests/057/aiken.lock
new file mode 100644
index 00000000..3a78b1e7
--- /dev/null
+++ b/examples/acceptance_tests/057/aiken.lock
@@ -0,0 +1,5 @@
+# This file was generated by Aiken
+# You typically do not need to edit this file
+
+requirements = []
+packages = []
diff --git a/examples/acceptance_tests/057/aiken.toml b/examples/acceptance_tests/057/aiken.toml
new file mode 100644
index 00000000..b47db6cd
--- /dev/null
+++ b/examples/acceptance_tests/057/aiken.toml
@@ -0,0 +1,3 @@
+name = "aiken-lang/acceptance_test_057"
+version = "0.0.0"
+dependencies = []
diff --git a/examples/acceptance_tests/057/lib/tests.ak b/examples/acceptance_tests/057/lib/tests.ak
new file mode 100644
index 00000000..8340046f
--- /dev/null
+++ b/examples/acceptance_tests/057/lib/tests.ak
@@ -0,0 +1,12 @@
+pub fn alt(left: Option<a>, right: Option<a>) -> Option<a> {
+  when (left, right) is {
+    (Some(a), Some(_)) -> Some(a)
+    (None, Some(a)) -> Some(a)
+    (Some(a), None) -> Some(a)
+    (None, None) -> None
+  }
+}
+
+test foo() {
+  Some(1) == alt(Some(1), Some(2))
+}