9.4 beta

note that with 9.4beta you will likely be forced to do a dump/restore to 9.4 stable when it comes out, and deprovision the beta database

~ ➤ heroku addons:add heroku-postgresql:standard-0 --version 9.4 --app will
Adding heroku-postgresql:standard-0 on will... done, v397 ($50/mo)
Attached as HEROKU_POSTGRESQL_OLIVE_URL
The database should be available in 3-5 minutes.
 ! The database will be empty. If upgrading, you can transfer
 ! data from another database with pgbackups:restore.
Use `heroku pg:wait` to track status
! WARNING: Postgres 9.4 is in beta. Beta releases have
!          a higher risk of data loss and downtime.
!          Use with caution..
Use `heroku addons:docs heroku-postgresql` to view documentation.