Show HN: Kuvasz – an open-source uptime and SSL monitoring service

Show HN (score: 8)
Found: July 04, 2025
ID: 97

Description

Monitoring/Observability
Show HN: Kuvasz – an open-source uptime and SSL monitoring service A few months ago I took out my side project - an uptime & SSL monitoring service - from the drawer. I've decided to give it a new life and completely overhauled it, added a lot of new feature, and most importantly, a UI.

Highlights

- configurable uptime & SSL monitoring

- Telegram, Slack, PagerDuty & E-mail notifications (more to come!)

- fully-fledged REST API

- a responsive, modern & fast UI

- monitors are optionally configurable via a single YAML file, or you can choose to use either the UI or the API to maintain them

- Cloud-native, distributed as amd64 and arm64 images

- Only one dependency: a PostgreSQL database to connect to

- Extensive examples in the docs

- stable memory usage (max ~360MB) & great performance

It's written in Kotlin, under the hood it uses Micronaut with Netty, jOOQ, and PostgreSQL, and the server-side-rendered UI is built with kotlinx.html, Alpine.js, and htmx.

It's called Kuvasz (pronounce as [ˈkuvɒs]), and you can find the repository here: https://github.com/kuvasz-uptime/kuvasz

And the website with the extensive documentation here: https://kuvasz-uptime.dev

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