--- title: "From Custom to Open: Scalable Network Probing and HTTP/3 Readiness with Prometheus" url: https://daily.dev/posts/from-custom-to-open-scalable-network-probing-and-http-3-readiness-with-prometheus-mittepodk source_url: https://slack.engineering/from-custom-to-open-scalable-network-probing-and-http-3-readiness-with-prometheus/ type: article source: "Slack engineering" published: 2026-03-31T17:08:04.990Z updated: 2026-03-31T17:08:29.966Z tags: ["monitoring", "prometheus"] reading_time: 5 upvotes: 45 comments: 1 language: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # From Custom to Open: Scalable Network Probing and HTTP/3 Readiness with Prometheus **[Slack engineering](https://daily.dev/sources/slack)** · 5 min read · 45 upvotes · 1 comments ## Summary Slack migrated from a third-party SaaS monitoring solution to an internally managed Prometheus-based network probing system. When rolling out HTTP/3 endpoints, they discovered a critical observability gap: no existing tools supported HTTP/3 (QUIC/UDP) probing. An intern, Sebastian Feliciano, implemented QUIC support for the Prometheus Blackbox Exporter using the quic-go library, contributed it upstream as an open-source PR, and also built an in-house solution to use the feature before the PR was merged. The result is a unified Grafana dashboard covering HTTP/1.1, HTTP/2, and HTTP/3 metrics, better alerting, and a community-available tool for HTTP/3 observability. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Prometheus and OpenTelemetry finally play nice](https://daily.dev/posts/prometheus-and-opentelemetry-finally-play-nice-2lupjc8qw) · The New Stack · 0 upvotes · 0 comments --- Tags: [#monitoring](https://daily.dev/tags/monitoring), [#prometheus](https://daily.dev/tags/prometheus) [View this post on daily.dev](https://daily.dev/posts/from-custom-to-open-scalable-network-probing-and-http-3-readiness-with-prometheus-mittepodk)