Repoker Uses Web Push and Cloudflare Workers to Wake Dead Extension Service Workers

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Developer tool Repoker implemented Web Push notifications to alert planning-poker teammates who are offline or inactive, solving a gap that persistent connections cannot address. Chrome's Manifest V3 extension service workers are killed after roughly 30 seconds of inactivity, making traditional keepalive techniques useless for reaching users who are not already in a session. The solution lets the service worker die completely and relies on the browser's push service to resurrect it only when a notification arrives, requiring no polling or heartbeat. Sending push notifications from a Cloudflare Worker required implementing VAPID authentication (RFC 8292) and per-message payload encryption (RFC 8291) directly using the Web Crypto API, avoiding Node.js-dependent packages. The result is a lightweight, standards-compliant notification pipeline that works with MV3's disposable-worker model rather than against it.

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ProgrammingDEV Community ·

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