Lightning Talk: Catching Performance Issues at Compile Time - Keith Stockdale - CppCon 2025

Added: 2026-05-08

This video demonstrates how to use custom type traits with static_assert to detect when callables are accepting arguments by value instead of by reference, transforming runtime performance issues into compile-time errors. The speaker, Keith Stockdale from Rare Ltd, presents a practical example where a missing ampersand in a lambda function caused significant server performance problems due to unnecessary copying of large objects. By implementing a type trait that checks if arguments are references, pointers, or small trivial types, developers can catch these bugs during compilation rather than runtime, preventing costly performance issues from reaching production.