Need NodeJS backend developer (high skilled)

Hi. We are looking for a skilled NodeJS backend developer to work on an existing application. If results are good, we can also offer a long-term contract. We use NodeJS for backend with MongoDB. Currently we need maintenance work on various modules, as well as the installation of a new payment system. Please apply only if you are very good at these specific technologies. We don't have time for training and beginner work. Thank you!