VCOT: OpenTelemetry Instrumentation for Vinyl-Cache

2025-11-20

We have opened the repository of VCOT (VinylCacheOpenTelemetry), a brand new open-source (GPL) Go utility designed to enhance observability in Vinyl-Cache (and, for the time being, Varnish-Cache) environments through an integration with OpenTelemetry.

Up until now Vinyl-Cache was able to produce highly-detailed logs and provide precise insight into the cache behavior, but it was not able to integrate with modern observability standards.

VCOT addresses the need for modern monitoring in high-performance systems by parsing Varnish Shared Logs (VSL) in real-time and exporting telemetry data - traces, metrics, and logs - to OpenTelemetry-compatible backends.

This is just the beginning, VCOT is destined to evolve based on users’ feedback. Please open issue and/or PRs if you wish to see this tool improve.