import { Config } from './types/config';
export declare class Mailer {
    private config;
    private transporter;
    constructor(config: Partial<Config>);
    /**
     * Use the same nodemailer config that couch-auth uses to send out an email.
     * Internally, `req` (the sent request), `user` (the sl-user doc) and `data`
     * defined in the config are always available.
     *
     * @param templateId the entry under the `emails` property in the config
     * @param recepient the recepient's email address
     * @param data additional data directly passed to `nunjucks.render()`. Don't
     * add anything called `data` in here!
     */
    sendEmail(templateId: string, recepient: string, data?: Record<string, any>): Promise<any>;
    private sendMailWithBackoff;
}