Looking for an experimented Ruby on Rails Developer

Hi, I am the co-founder of Kube ([login to view URL]): a subscription allowing to receive every month a book chosen for each reader by an independent bookseller. The process by which we ship a custom book for each customer is as follows: -Each month the reader fills in a reading request (reply to a questionnaire) -This reading request is attributed to a bookseller -The bookseller analyses the customer's reading request and selects for him the book corresponding perfectly to the customer's request. -We order this book and ship it in a beautiful box to the customer This whole process is managed via a ruby on rails web application ([login to view URL]). Our lead developer is based in Brazil and has more and more difficulty to do everything alone (he is not full time). We are looking for a flexible developer who will be able to help him and gradually increase in power, if necessary until a full time. To start the cruising pace would be 2 to 3 hours of work/day (5 days/week), or something like 2 days/week. The job will start with development of features linked to the launch of a new subscription for kids. We are looking for an experienced developer. Having already worked with Stripe is a considerable plus. We are looking for someone within the European Union. Do not hesitate for any question. Thanks, Samuel.