# Sloth

> Apache-2.0 SLO generator for Prometheus rules and alerts

**Category:** Observability  
**Pricing:** open-source  
**URL:** https://sloth.dev  
**GitHub:** https://github.com/slok/sloth  
**Added:** 2026-10-18

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## The Hook

Sloth generates reliable Prometheus SLOs from a small spec: write your service's SLI and objective, and it produces recording rules, metadata rules and multi-window, multi-burn-rate alerts.

## What's Good

Apache-2.0 (slok/sloth), release v0.16.0 (2026-04-04). Based on Google's SLO approach. Works as a CLI in CI, a Kubernetes controller with a CRD, or a library, with SLI plugins for common cases and Grafana dashboards for the results. Supports OpenSLO specs too. ★~2.6k.

## The Catch

It only generates rules; Prometheus and Alertmanager still do the work, and you must choose good SLIs. The last release was April 2026, and the project status says internal refactoring is in progress. Single-maintainer project.

## Verdict

The easiest correct way to get burn-rate SLO alerts in Prometheus.