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Are there plans to switch this from JSONb to aeson? I hear aeson is the new hotness.
Currently, JSONb is tied to attoparsec 0.8, blocking the upgrade of things which depend on attoparsec 0.9 (e.g. Yesod 0.9) for repackaging that only allows one version of a package at a time. Ideally, JSONb would be upupdated, but then mention of AESON on the JSONb hackage page makes it sound deprecated.
If you don't have time, and don't think it would be too involved, I might try taking a stab at it?
Even simpler, looks like JSONb's been updated to support attoparsec 0.9 (it was just a cabal file limit). Sorry for the noise.