To be honest I see 2 use-cases for dynamic list: * Fast prototyping: but a full blown dynamic language is probably better suited for that. * Heterogeneous collections: when you need heterogeneous collections, you have usually have a very specific need (collection of Animals: dog, cat, etc ...) with very specific methods (eat, sleep, hunt) that a generic collection does not cover so it's written from scratch anyway.
What is often requested is a way to generate a common interface for various types, it is being work on using Nim concepts, and here is a current implementation using macros: [https://github.com/andreaferretti/interfaced](https://github.com/andreaferretti/interfaced)
