diff --git a/fizz/protocol/Certificate.h b/fizz/protocol/Certificate.h
index 20dbd982b23..39611211331 100644
--- a/fizz/protocol/Certificate.h
+++ b/fizz/protocol/Certificate.h
@@ -26,8 +26,9 @@ using IdentityCertBase = Cert;
 
 #else
 namespace fizz {
-struct Cert {
-  virtual ~Cert();
+class Cert {
+ public:
+  virtual ~Cert() = default;
   virtual std::string getIdentity() const = 0;
 };