diff --git a/bin/postprocess-openapi.py b/bin/postprocess-openapi.py
index 552cfcb..5a6a966 100755
--- a/bin/postprocess-openapi.py
+++ b/bin/postprocess-openapi.py
@@ -43,5 +43,17 @@ for path, methods in paths.items():
         op.setdefault("operationId", op_id(method, path))
         op.setdefault("tags", [path.strip("/").split("/")[1] if "/" in path.strip("/") else "default"])
 
+# oatpp 1.3 emits `"required": []` on schemas that have no required fields.
+# OpenAPI 3.0.x rejects this (`must NOT have fewer than 1 items`), which
+# breaks strict consumers like Orval's Zod generator. Strip empty arrays —
+# absence of the keyword has the same semantics.
+schemas = spec.get("components", {}).get("schemas", {})
+stripped = 0
+for sch in schemas.values():
+    if isinstance(sch, dict) and sch.get("required") == []:
+        del sch["required"]
+        stripped += 1
+
 SRC.write_text(json.dumps(spec, indent=2))
-print(f"  postprocessed {SRC} — {len(paths)} paths")
+print(f"  postprocessed {SRC} — {len(paths)} paths"
+      + (f", stripped empty `required` from {stripped} schemas" if stripped else ""))
diff --git a/package.json b/package.json
index 564f14c..ad527b1 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@uschuster/webapp-scaffold",
-  "version": "0.4.0",
+  "version": "0.4.1",
   "description": "Shared build scripts + Vite config factories for webapp-template-derived projects.",
   "type": "module",
   "bin": {