This post gives you crisp mental models and copy‑pasteable patterns for three frequently‑confused topics:

MVVM (Model–View–ViewModel)

Micro‑Frontends (MFE)

Domain‑Driven Design applied to the frontend ( DDF/DDD )

TL;DR: Use MVVM to structure components, DDD to structure the system/domain , and micro‑frontends only when org/scale complexity requires independent deploys.

Quick Compare (When to use what)

Concern MVVM DDD (frontend) Micro‑Frontends

Primary goal Decouple UI from state/logic Align codebase with business domains & boundaries Scale teams with independent deploys

Granularity Component/feature level App/system architecture App/organization level

Key benefits Testable UI logic, clearer components Low coupling, shared language, safer changes Team autonomy, parallel delivery

Typical cost Extra layer (ViewModel) Upfront modeling + boundaries Runtime integration, perf, shared deps

Use if… Components mix view & logic Features cross‑contaminate domains Many teams, large app, diff release…