midPWA

What is Service Worker lifecycle?

Updated May 17, 2026

Short answer

It includes install, activate, and fetch phases.

Deep explanation

Service Workers go through install (cache setup), activate (cleanup old caches), and fetch (request interception).

Real-world example

Updating PWA versions in production apps.

Common mistakes

  • Not handling old cache cleanup.

Follow-up questions

  • What triggers activation?
  • Can SW skip lifecycle?

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