import type { UserConfig } from '../types.js';
declare type UserConfigFNReturnType = UserConfig | Promise<UserConfig>;
declare type DefineConfigReturnType = Promise<UserConfig | undefined>;
declare function defineConfig(config: UserConfig): DefineConfigReturnType;
declare function defineConfig(config: (config: UserConfig) => UserConfigFNReturnType): DefineConfigReturnType;
export default defineConfig;