The idea of reproducibility I want to base Derctuo on requires some explanation, since there isn't anything else out there that aims at this, as far as I can tell.
The objective of Derctuo's virtual-machine design is that running the same program with the same inputs always reproduces bitwise-identical outputs, unless it fails; that this should be the case even when executed on independent cleanroom reimplementations from the specification, whether this year or in 300 years, on the same hardware or different hardware; that implementing the virtual machine from the spec should require only a few hours of work; and that this virtual machine should be sufficient to reproduce all the computations I think are interesting.