Angular Modernization: From Zones to Signals in 30 Days
A focused, time-boxed plan to retire legacy patterns and unlock performance budgets.
Back to all postsLegacy Angular applications that lean on zone.js and sprawling NgRx stores often resist incremental change. Instead of flipping a single giant switch we tackle the modernization in four themed sprints.
Sprint 1 isolates critical flows and hardens test coverage. Component contracts become explicit, analytics events are audited, and hydration blockers are catalogued.
Sprint 2 introduces Signals for localised state. We replace brittle selector pyramids with focused computed state and push side effects to services.
Sprint 3 prepares the rendering pipeline for SSR and fine-grained change detection. We remove global pipes, audit dependency injection, and verify accessibility now that components rerender predictably.
Sprint 4 is about observability and load testing. We set up lab and field performance budgets, run the app through Web Vitals, and capture a final baseline that leadership can broadcast company-wide.
Key takeaways
- Treat modernization as themed sprints with explicit exit criteria.
- Introduce Signals around the most volatile UI state first.
- Back every refactor with lab and field telemetry so improvements stay visible.
Implementation checklist
- Document SSR and hydration blockers before touching templates.
- Refactor shared state to Signals backed by typed contracts.
- Establish Web Vitals and performance budgets ahead of the final cutover.