Chain a subset of tasks

I have a container of N Tasks and I would like to add a continuation of n of these N tasks. The problem is that both n and N are only known at runtime. My best idea was to create a vector of reference_wrapper of the n tasks but it does not work.

I understand you do not develop this library anymore but do you have an idea of how to manage this? Or how to modify Async++ to add this feature? Or do you know other libraries that could do it?

Thanks a lot for your help