> > > @CShepartd Could you please give us a concrete example what would you use `Int128`/`UInt128` for? I would like to implement a 64-bit version of the PCG family of RNGs but currently have to resort to software emulation. The fact that we have to even argue the usefulness of such a feature is absurd; you wouldn't ask us to justify the reasons for supporting 16-bit, 32-bit, or 64-bit integers so why are 128-bit integers any different? It's simple math; anyone who wants or needs to perform multiplication on 64-bit numbers absolutely requires support for 128-bit integers. The hardware that the vast majority of us write programs for has had this ability since at least the original release of the AMD64 instruction set; it is about time that .NET catches up.