core-js 3 feature-path migration: side-by-side version serving during zero-downtime rollout
Migrating a small application from core-js 2 to core-js 3 without downtime crosses a documented module boundary: core-js/fn/... specifiers become core-js/features/... , and aggregate entry points such as core-js/stable become available. In Babel, the configuration transition moves @babel/preset-env from corejs: 2 to corejs: 3 under useBuiltIns . The unresolv
corejs