[trenchant]

Thanks. I thought I noticed a Haskell logo sticker on that developer's laptop in the photo...

[vdijkbas]

That's me and my laptop :-)

As I mentioned in the reddit comments we're using Haskell for most parts of the system (frontend via GHCJS, web application servers, protocol implementations). For dev-ops we use the Nix ecosystem: NixOS & nixops.