[Nix-dev] [***SPAM***] Re: [***SPAM***] Re: Nixpkgs and NixOS moved to GitHub

[Michael Raskin]

>> (like in the case with the 
>>parallel builds)
>
>What's the story with parallel builds?

There was a proposal to introuce off-by-default support for parallel
builds on multicore computers. There was a patch that allowed user to
choose whether he wants to do the risky thing and use parallel builds.
Known-bad packages could be easily blacklisted - and with overrides it
would be easy to try blacklisting locally. 

The code that eventually landed in trunk requires explicit whitelisting
even though parallel builds require manual enabling. As far as I 
remember, adding package to the whitelist causes a rebuild. There is no
option to go back to blacklisting. You need to opt-in globally, then 
additionally opt-in per-package.

Of course, this code has to be in stdenv, so fixing it is costly.