Resilient Import Maps - Better Theme Development and Beyond (2025) - Shopify
5/28/2025
Shopify identified and addressed two key limitations in the import map specification: the restriction that no module could load before the import map, and the single import map per document rule. They collaborated on a plan that introduced a reconciliation mechanism involving a global import map representation and a resolved module set. A merge algorithm was developed to handle new import maps by dropping rules that would impact already loaded modules and resolving conflicts with existing rules. This change was submitted to the HTML spec, implemented in Chromium and WebKit, and shipped in recent browser versions. Shopify also integrated es-module-shims for older browser support.
