Hydra unilaterally removed hydra-eval-jobs, so we need to figure out how
to migrate to nix-eval-jobs. I can't shake the feeling that it's slower.
Maybe we need to increase the resource limitations for nix-eval-jobs.
nix-eval-jobs no longer produces a big JSON object, but instead one
object per line (one for each job). This is supported in a simple way by
readJSONLinesProcess. It'd be possible to implement this without
presupposing that there's one object per line, however, it is not an
usecase exactly intended by aeson, it seems.
nix-eval-jobs makes our job easier in some ways, e.g. jobs have a proper
meta set now, so we no longer need to cross reference a mail address to
github handle map. There is even room for further improvement, e.g.
attribute paths can just be queried instead of generating them using
Text.splitOn.
See also https://github.com/NixOS/hydra/pull/1421.
bbefb1d462