loglayer-go is a unified logger that routes logs to various logging libraries, cloud providers, files, terminals, and OpenTelemetry while providing a fluent API for specifying log messages, fields, metadata, and errors.

Requires Go 1.25+ for the main module.

For full documentation, read the docs.

// Example using the Structured (JSON) transport.
// You can start out with one transport and swap to another later
// without touching application code.
import (
    "errors"

    "go.loglayer.dev/v2"
    "go.loglayer.dev/transports/structured/v2"
)

log := loglayer.New(loglayer.Config{
    Transport: structured.New(structured.Config{}),
    // Put fields under "context" and metadata under "metadata"
    // (defaults are flattened to the root).
    FieldsKey:         "context",
    MetadataFieldName: "metadata",
})

// Persistent fields that appear on every subsequent log
log = log.WithFields(loglayer.Fields{
    "path":  "/",
    "reqId": "1234",
})

log.WithPrefix("[my-app]").
    WithError(errors.New("test")).
    // Data attached to this log entry only
    WithMetadata(loglayer.Metadata{"some": "data"}).
    Info("my message")

{
  "level": "info",
  "time": "2026-04-26T12:00:00Z",
  "msg": "[my-app] my message",
  "context": {
    "path": "/",
    "reqId": "1234"
  },
  "metadata": {
    "some": "data"
  },
  "err": {
    "message": "test"
  }
}

• Install
• Documentation
• TypeScript counterpart
• Contributing
• Issues and questions
• License

go get go.loglayer.dev/v2

For detailed documentation, visit go.loglayer.dev.

Coming from loglayer for TypeScript? See For TypeScript Developers for the API mapping and Go-specific differences.

This is a multi-module repo: the framework core lives at the root (go.loglayer.dev/v2); every transport, plugin, and integration ships as its own independently-versioned Go module under transports/, plugins/, and integrations/.

• Dev-loop on-ramp (prerequisites, hooks, make targets, commits, tests, docs, releases via monorel): CONTRIBUTING.md.
• Architectural context (multi-module split, thread-safety contract, performance log, release flow internals): AGENTS.md.

transports/blank/ is the copyable template for adding a new transport, plugin, or integration; the full recipe is in AGENTS.md → Adding a new transport, plugin, or integration.

Bug reports, feature requests, and architectural questions go in GitHub Issues.

MIT

Made with ❤️ by Theo Gravity / Disaresta. Logo by Akshaya Madhavan.