Starting immediately, Stackage nightly builds will be stepping back from aeson-0.10.0.0 to aeson-0.9.0.1. Due to issues with aeson-0.10, we are planning to discontinue LTS 4. Next Sunday (2016-01-24) we will begin LTS 5, which will ship with aeson-0.9.
Under normal circumstances, the support duration of an LTS Haskell series is 3 months at minimum. We believe that, in retrospect, the inclusion of aeson-0.10 in LTS Haskell was premature, and we felt it necessary to take quick action to reverse this mistake. We anticipate that LTS 5 and onward will be supported for the usual 3+ months.
Looking forward, we hope that LTS 6 (around April/May 2016) will be able to incorporate ghc-8. Several patches for aeson can be seen in the pipeline, so we also hope that LTS 6 will be able to include a new version of aeson with all of these improvements. Aeson is a key component of the Haskell ecosystem, and we thank Bryan O’Sullivan and aeson contributors for the hard work that has gone into it. We also thank all of the downstream package authors that have been working hard to keep pace.