diff --git a/wdl/structs/Structs.wdl b/wdl/structs/Structs.wdl
new file mode 100644
index 0000000..eef96b9
--- /dev/null
+++ b/wdl/structs/Structs.wdl
@@ -0,0 +1,16 @@
+version 1.0
+
+struct RuntimeAttr {
+    Float? mem_gb
+    Int? cpu_cores
+    Int? disk_gb
+    Int? boot_disk_gb
+    Int? preemptible_tries
+    Int? max_retries
+    String? docker
+}
+
+struct DataTypeParameters {
+    Int num_shards
+    String map_preset
+}