Log Level

Controlling the verbosity of logs during the bundling process helps you focus on what matters most. The recommended way to manage log output in tsdown is by using the --log-level option.

Usage

To suppress all logs—including errors—set the log level to silent:

tsdown --log-level silent

To display only error messages, set the log level to error:

tsdown --log-level error

This is useful for CI/CD pipelines or scenarios where you want minimal or no console output.

Available Log Levels

• silent: No logs are shown, including errors.
• error: Only error messages are shown.
• warn: Warnings and errors are logged.
• info: Informational messages, warnings, and errors are logged (default).

Choose the log level that best fits your workflow to control the amount of information displayed during the build process.

Fail on Warnings

The failOnWarn option controls whether warnings cause the build to exit with a non-zero code. By default, this is set to 'ci-only', which means warnings will cause the build to fail in CI environments but not locally.

This default behavior ensures that CI pipelines catch potential issues while keeping local development uninterrupted.

tsdown.config.ts

import { defineConfig } from 'tsdown'

export default defineConfig({
  // Default: fail on warnings only in CI
  failOnWarn: 'ci-only',
  // Always fail on warnings
  // failOnWarn: true,
  // Never fail on warnings
  // failOnWarn: false,
})

See CI Environment for more about CI-aware options.