diff --git a/tests/fixtures/nested.env b/tests/fixtures/nested.env
new file mode 100644
index 0000000..85804af
--- /dev/null
+++ b/tests/fixtures/nested.env
@@ -0,0 +1,10 @@
+# Nested configuration
+DB_HOST=localhost
+DB_PORT=5432
+DB_USER=postgres
+DB_PASSWORD=secret
+DB_NAME=myapp
+REDIS_HOST=localhost
+REDIS_PORT=6379
+API_URL=https://api.example.com
+API_TIMEOUT=30