Whether you get benefit from going 2.8→2.9→3.0 (over just going 2.8→3.0) is probably a factor of how big and complicated the project being upgraded is (see also https://github.com/guardian/maintaining-scala-projects/issues/4) - I'd guess Facia Tool is quite big, so breaking the changes down into smaller chunks might be worth it in terms of avoiding risk.
Obviously we're encouraging people to get onto Play 3.0 to avoid the Akka BSL licensing issue!
Note also that Play 2.9 actually uses Play-Json 2.10, which is a bit surprising!
Whether you get benefit from going 2.8→2.9→3.0 (over just going 2.8→3.0) is probably a factor of how big and complicated the project being upgraded is (see also https://github.com/guardian/maintaining-scala-projects/issues/4) - I'd guess Facia Tool is quite big, so breaking the changes down into smaller chunks might be worth it in terms of avoiding risk.
Obviously we're encouraging people to get onto Play 3.0 to avoid the Akka BSL licensing issue!
Note also that Play 2.9 actually uses Play-Json 2.10, which is a bit surprising!