diff --git a/src/integration_tests/calc_test.rs b/src/integration_tests/calc_test.rs
new file mode 100644
index 0000000..871724a
--- /dev/null
+++ b/src/integration_tests/calc_test.rs
@@ -0,0 +1,4 @@
+#[test]
+fn test_add_one() {
+    assert_eq!(crate::unit_tested_file::add_one(1), 2);
+}
\ No newline at end of file
diff --git a/src/integration_tests/mod.rs b/src/integration_tests/mod.rs
new file mode 100644
index 0000000..caed048
--- /dev/null
+++ b/src/integration_tests/mod.rs
@@ -0,0 +1 @@
+mod calc_test;
\ No newline at end of file
diff --git a/src/lib.rs b/src/lib.rs
index d1ffcea..664b12f 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -6,6 +6,10 @@
 
 // mod doc_test; 
   // todo: failed to resolve: use of undeclared crate or module `doc_test`
+
+#[cfg(test)]
+mod integration_tests;
+
 mod async_;
 mod averaged_collection;
 mod cfg;