Senior React.js developer

We are working hard to complete the key parts of our healthtech project and we need in our Front-end development to catch up with back-end progress. We have a specific scope of screens and modals in mind but if the project is successful this can turn into a much longer collaboration. Our react.js front-end is quite tightly integrated with our PHP Symfony-based back-end, so some experience with both would be useful to get up to speed as soon as possible.
Here is a bit more about the tech stack in question: tech-stack: