# Tweet by [@keefmoon](http://twitter.com/keefmoon) on 2019-06-01 23:54:46 > [!INFO] Archived from [original tweet](http://twitter.com/keefmoon/status/1134971581434908673) A word to the wise: Trying to prototype a custom collection view layout in a Swift Playground is useful, but something about the playground live view is really inefficient, which leads to huge UI stuttering.