Since late 2017, Phabricator's roadmap is completely driven by requests from paying customers through Support Pacts.
Effectively, we now auction the roadmap to the highest bidder. Since customer needs change rapidly, the roadmap also changes too rapidly to make maintaining a dedicated roadmap document useful.
For details on recent, ongoing, and upcoming iterations based on requests from customers, see Plans.
For discussion of the planning process, see Planning.
For long-term plans over the coming years, see the Starmap.