link-verify

A Manifest V3 browser extension and self-hosted Node.js backend that give a research team shared, real-time awareness of which links each member has visited. Anchors recolor live as teammates work: unclicked, clicked by you, or clicked by a teammate.

The technical core is a 685-line URL canonicalizer, shared between the content script and the API server and covered by its own 33-test suite. It strips 200+ tracking parameters and normalizes place identifiers, so semantically identical URLs collapse to one canonical form, each SHA-256 fingerprinted for fast lookup.

A standalone WebSocket server fans click, typing, and read-receipt events out to every connected device, with heartbeat dead-connection detection, per-user connection caps, and flood protection. The client runs its own exponential-backoff auto-reconnect. The 45-endpoint Express backend spans two datastores: MongoDB for users, clicks, and chat, and a relational pool backing an image-verification workflow with client-side EXIF/GPS/copyright extraction and a visual matching tool.

The front end is a disciplined 74-module ES6 codebase (~17.4K lines) with a custom Rollup build, four-language localization, and a self-hosted update channel. It was re-architected from a v1 monolith into single-responsibility modules and is deployed for internal team use.