diff --git a/include/aidge/backend/cpu/operator/OperatorImpl.hpp b/include/aidge/backend/cpu/operator/OperatorImpl.hpp
index b11f952e0a9fdd7c3e8793dc23a8f0d1fd3a3cb5..4e3100ec4172861c7341776f96c44f5c4032cb47 100644
--- a/include/aidge/backend/cpu/operator/OperatorImpl.hpp
+++ b/include/aidge/backend/cpu/operator/OperatorImpl.hpp
@@ -38,7 +38,7 @@ public:
         return impl.prodConso(mOp);
     }
 
-    virtual std::vector<ImplSpec> getAvailableImplSpecs() const override {
+    virtual std::set<ImplSpec> getAvailableImplSpecs() const override {
         return Registrar<OperatorImpl_cpu>::getKeys();
     }