🦥 Sloth V0.15.0: Go Library & Live SLO Editor

[slok]

Hey everyone! 👋

I'm excited to announce Sloth v0.15.0, this is a major milestone for the project!

🎯 What's New

Go Library Support 🚀

Sloth is no longer just a CLI tool, you can now embed Sloth's SLO generation logic directly into your Go applications! It supports all sloth cool features like the SLI and SLO plugins. This opens up entirely new use cases:

• Build custom SLO generation APIs that generate rules on-demand.
• Integrate Sloth into your internal platforms and developer portals.
• Create custom workflows that combine Sloth with your existing tooling.
• Extend and customize the SLO generation process beyond what the CLI offers.
• ...

Check out the docs, run go get github.com/slok/sloth@v0.15.0 and release the 🦥!.

Example

package main

import (
	"context"
	"fmt"
	"os"

	sloth "github.com/slok/sloth/pkg/lib"
)

const sloSpec = `---
version: "prometheus/v1"
service: "myservice"
slos:
  - name: "example-slo"
    objective: 99.9
    description: "A simple example SLO."
    sli:
      events:
        error_query: sum(rate(metric1{job="myservice",bad="true"}[{{.window}}]))
        total_query: sum(rate(metric1{job="myservice"}[{{.window}}]))
    alerting:
      page_alert:
        disable: true
      ticket_alert:
        disable: true
`

func main() {
	ctx := context.Background()

	gen, err := sloth.NewPrometheusSLOGenerator(sloth.PrometheusSLOGeneratorConfig{})
	if err != nil {
		panic(fmt.Errorf("could not create SLO generator: %w", err))
	}

	// Generate SLOs.
	result, err := gen.GenerateFromRaw(ctx, []byte(sloSpec))
	if err != nil {
		panic(err)
	}
	err = gen.WriteResultAsPrometheusStd(ctx, *result, os.Stdout)
	if err != nil {
		panic(err)
	}
}

Live SLO Editor ✨

Thanks to the Go library, we've built something really cool: a fully sandboxed SLO editor that runs 100% in your browser using WebAssembly!

Try it now at https://live.sloth.dev, create, test, and validate your SLOs instantly without installing anything. Perfect for:

• Learning Sloth and experimenting with SLO specs
• Quick prototyping and testing
• Sharing SLO examples with your team
• Teaching SLO concepts

🔧 Under the Hood

This release required significant architectural work to make Sloth's core logic library-friendly while maintaining full backward compatibility, although this didn't happen in this single release. The SLO generation engine is now cleanly separated and can be consumed programmatically, which made possible to power both the WASM editor and now enables you to build custom integrations.

🔮 What's Next?

It will be related with SLO generated output formats, stay tuned.