Jean M. Sexton

This scales only the problem domain, not fields which also might relate to the length scale such as velocity, right?

Nyx does what Weiqun mentioned for SUNDIALS, where we use cmake to compile sundials libraries, and link against them when using gnumake to create a Nyx executable. For the on-the-fly...

I concur that tracking which compiler version things are built with and updating/comparing things appropriately is non-trivial. I don't necessarily think having a mega-build where amrex builds all the libraries...