What repeatedly goes wrong.
ADDING A FRAMEWORK A CONTENT SITE DID NOT NEED
REBUILDING NATIVE ELEMENTS
Losing keyboard handling and accessibility.
PUTTING EVERYTHING IN GLOBAL STATE
Making the application difficult to reason about.
TREATING SERVER DATA AS OWNED STATE
Producing manual loading flags and stale data everywhere.
STORING DERIVED VALUES
Creating copies that diverge.
USING EFFECTS FOR THINGS THAT BELONG ELSEWHERE
Producing extra renders and subtle bugs.
MEMOISING WITHOUT MEASURING
Complexity for no benefit.
ADDING DEPENDENCIES CASUALLY
Each downloaded, parsed and executed by every visitor.
DESIGNING ONLY THE SUCCESSFUL STATE
Empty, error and loading discovered in production.
NO PERFORMANCE BUDGET
Degradation nobody notices until it is severe.
TESTING IMPLEMENTATION RATHER THAN BEHAVIOUR
Tests that break on every refactor.
NO CONVENTION FOR WHERE THINGS LIVE
WHAT PREVENTS MOST OF THESE
Keeping state minimal, starting from native elements, measuring before optimising, and agreeing conventions early.
