Manu:
I would do that to start with, but the difference is that if I work with phobos in mind, then I'll raise design discussion here, otherwiseI'll just keep it to myself.
I think having a color module in Phobos is OK. But probably it's better to write it with Phobos in mind but to keep it in code.dlang for some time, like one year, to refine its API, before adding it to Phobos.
Bye, bearophile