How import maps and ES modules simplify micro-frontend architecture

A developer has outlined a micro-frontend strategy called Runtime Module Composition (RMC), built on browser-native ES modules and import maps to help independent teams own, deploy, and update their code without shared build pipelines. Import maps, a standardized browser feature, act as a lookup table that redirects module imports to specific URLs at runtime, eliminating the need for bundlers or custom module loaders. The approach addresses a common problem in large web products where multiple teams share a single page and a tangled build configuration. A small open-source toolkit called rmc-toolkit generates import maps from a single shared manifest, which also drives build configuration and URL-based routing automatically. Updating a dependency version in the manifest propagates the change across the import map, build tooling, and router without requiring manual synchronization.