The Heft 0.51.0 release introduces a "multi-phase" feature that brings some significant architectural changes. If you've been using an older version, upgrading will require making some changes to your Heft config files and also any custom plugins that you may have authored. In this post, we'll summarize what changed and how to migrate your projects. This is probably the last major breaking change before the 1.0.0 release of Heft.
"Multi-phase" Heft is a major update for the @rushstack/heft project with the goal of integrating more closely with Rush phased builds. In addition, this update brings greater customizability and improved parallel process handling to Heft. This post explains the motivation and architecture behind these improvements.