<makefu>
what exactly is an evaluation in nix? i am trying to add this information to the hydra page to describe the two phases. i know in general that the evaluation will result in some kind of thing which in turn can be built
<gchristensen>
evaluation interprets the nix code and converts it to .drv files
<makefu>
gchristensen: but when hydra performs an "evaluation" it expects it to return an attrset of derivations? A derivation is essentially a build description, correct?
<gchristensen>
hydra basically runs `nix-instantiate .` in the root of the repo
<gchristensen>
it then puts each .drv outputted in to a queue for `nix-build`ing
<gchristensen>
* it doesn't literally run nix-instantiate, but it is essentially the same. the difference lies in that evaluation errors in nix-instantiate scuttles the whole thing, and hydra can continue
<gchristensen>
does that make sense?
<makefu>
yep,definitly. a .drv file is essentially the build recipe, right?
<gchristensen>
uhh yeah I suppose so
<gchristensen>
you should look at one
<gchristensen>
"nix show-derivation nixpkgs.git ~
<makefu>
the power of nix2
<gchristensen>
"nix show-derivation nixpkgs.git"
<makefu>
fantastic
<makefu>
not sure why derivations are not simply json files