#lib.format

• Type: 'esm' | 'cjs' | 'umd' | 'mf' | 'iife'
• Default: 'esm'
• CLI: --format <format> (e.g. --format umd)

Specify the output format for the generated JavaScript output files.

For different output formats, Rslib uses the following default value of output.library.type provided by Rspack:

• esm：modern-module
• cjs：commonjs-static
• umd：umd
• iife: module with output.iife enabled.

See Output Format and Module Federation for more details.