Please find the latest 4x version (4.1.7 at time of writing) at npm: Importing client and types for browser or node:
import UpgradeClient from 'upgrade_client_lib/dist/browser';
import UpgradeClient from 'upgrade_client_lib/dist/node';
General UpGrade types can also be accessed as named exports:
import UpgradeClient, { IExperimentAssignment } from 'upgrade_client_lib/dist/browser';
SDK-Specific types can be accessed also:
import { Interfaces } from 'upgrade_client_lib/dist/clientlibs/js/src/identifiers'; const initResponse: Interfaces.IUser = await upgradeClient.init();