diff --git a/lib/netstd/Thrift/Protocol/TBinaryProtocol.cs b/lib/netstd/Thrift/Protocol/TBinaryProtocol.cs
index 6389184..186d220 100644
--- a/lib/netstd/Thrift/Protocol/TBinaryProtocol.cs
+++ b/lib/netstd/Thrift/Protocol/TBinaryProtocol.cs
@@ -475,7 +475,13 @@
             protected readonly bool StrictRead;
             protected readonly bool StrictWrite;
 
-            public Factory(bool strictRead = false, bool strictWrite = true)
+            // emtpy default CTOR required
+            public Factory()
+                : this(false, true)
+            {
+            }
+
+            public Factory(bool strictRead, bool strictWrite)
             {
                 StrictRead = strictRead;
                 StrictWrite = strictWrite;