Transports

Transports decide where logs go. Sawdust splits them in two:

• Core transports — console, pretty, consola. Configured under the transports object in configureLogger. Built into @cues/sawdust, no extra install.
• Provider transports — Datadog server/browser logs. Shipped as factories in the separate @cues/sawdust-datadog package and wired through extraTransports. Core stays provider-agnostic; see Providers.

All of them are built on top of LogLayer.

Availability by runtime

Transport	Package / seam	Node	Browser	Worker	Purpose
console	core · transports	✅	✅	✅	Native console / stdout / stderr.
pretty	core · transports	✅	✅	✅	Human-friendly terminal / dev-console output.
consola	core · transports	✅	✅	✅	Consola-backed output.
datadogTransport	@cues/sawdust-datadog · extraTransports	✅	—	✅	Datadog server logs intake.
datadogBrowserTransport	@cues/sawdust-datadog/browser · extraTransports	—	✅	—	Datadog browser logs SDK.

Core transports

Enable any combination under transports in configureLogger.

console

console: {
  enabled: true,
  level: 'info',
  appendObjectData: true,   // print context object alongside the message
  stringify: true,          // emit JSON lines (great for log shippers)
  messageField: 'msg',      // JSON field names when stringify is on
  dateField: 'ts',
  levelField: 'level',
  stream: 'stderr',         // 'stdout' | 'stderr'
}

Structured JSON preset

For MCP servers and log shippers, the common shape is { stringify: true, messageField: 'msg', dateField: 'ts', levelField: 'level', stream: 'stderr' }. Centralize it so every service emits identical JSON.

pretty

pretty: {
  enabled: process.env.NODE_ENV === 'development',
  runtime: 'node',          // 'node' | 'browser'
  viewMode: 'inline',       // 'inline' | 'expanded'
  timestampFormat: 'mm:ss',
  includeDataInBrowserConsole: true,
}

consola

consola: {
  enabled: true,
  createOptions: { level: 5 },
}

Provider transports (@cues/sawdust-datadog)

Datadog no longer lives inside the transports object. Install the provider package and pass its factory results into extraTransports (and, for APM correlation, plugins).

pnpm add @cues/sawdust-datadog

datadogTransport (server logs)

import { datadogTransport } from '@cues/sawdust-datadog'

extraTransports: [
  datadogTransport({
    service: 'orders-api',
    logLevel: 'info',
    apiKey: process.env.DD_API_KEY,
    enableInDev: false,
    options: { ddsource: 'nodejs', ddtags: 'env:prod' },
  }),
]

Returns undefined when apiKey is missing; Sawdust skips falsy extraTransports entries.

Pairs with APM trace injection (a plugin, not a transport) so logs correlate to traces:

import ddTrace from 'dd-trace'
import { datadogTraceInjectorPlugin } from '@cues/sawdust-datadog'

plugins: [
  datadogTraceInjectorPlugin({
    apiKey: process.env.DD_API_KEY,
    tracer: ddTrace.init(),
    service: 'orders-api',
    environment: 'production',
  }),
] // Node only; returns undefined without both apiKey and tracer

datadogBrowserTransport (browser logs)

Requires the optional peer dep @datadog/browser-logs.

import { datadogBrowserTransport } from '@cues/sawdust-datadog/browser'

extraTransports: [
  datadogBrowserTransport({
    service: 'my-web-app',
    environment: 'prod',
    version: '1.0.0',
    logLevel: 'info',
    enabled: !!window.__DATADOG_CLIENT_TOKEN__,
    init: {
      clientToken: window.__DATADOG_CLIENT_TOKEN__,
      forwardErrorsToLogs: true,
      sessionSampleRate: 100,
    },
  }),
]

Returns undefined when init.clientToken is missing.

RUM

RUM is not a log transport — it is a separate browser subsystem reached through @cues/sawdust-datadog/rum. See the RUM guide. It requires the optional peer dep @datadog/browser-rum. Error-to-RUM forwarding is opt-in via the datadogRumErrorPlugin() plugin.

Merging overrides

Provide a subset of any core transport's options and Sawdust merges them over the defaults — you only specify what differs from the environment's baseline.