Import sub-modules (npm sub-path support)

When adding an npm module to a server script, you can optionally specify a sub-path to import a specific sub-module instead of the root package.

This allows you to:

  • Import only the functionality you need

  • Use modern Node.js APIs (e.g. fs/promises)

  • Match standard JavaScript import patterns such as lodash/debounce

When a sub-path is provided when the module is added to the script, the server script runtime resolves the module as:

<module>/<sub-path>

The resolved export is exposed in the script via the configured module context name.

Examples

Named export

  • Module: date-fns

  • Sub-path: format

const { format } = modules.datefns;
const result = format(new Date(), 'yyyy-MM-dd');
console.log(result);
Some sub-modules expose named exports and must be accessed via restructuring.

Default export (function)

  • Module: lodash

  • Sub-path: debounce

const debounce = modules.lodash;
const log = (msg) => console.log(msg);
const debouncedLog = debounce(log, 300);
debouncedLog('hello');

Node.js built-in module

  • Module: fs

  • Sub-path: promises

const fs = modules.fs;
const content = await fs.readFile('/tmp/test.txt', 'utf8');
console.log(content);

Sub-path support preserves the original export behavior of each package. Always consume the module according to how it is defined by the package author.

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