Frontend/Backend/Fullstack Developer

The client is a startup developing software for agricultural businesses and currently looking for one or more freelancers for frontend development with Angular and/or backend development with Java. The optimal candidate would cover both areas.
The freelancer will be part of a Scrum team which consists of 5-6 developers. For that reason the client would like the freelancer to work only onsite.
The tasks are to implement new features, further develop existing functionalities and bugfixing.
In the frontend the customer still uses Angular 1.6 but they are switching to Angular 5 at the moment. In the backend they are using Java and Spring Boot.
A longer-term cooperation of at least 6 months is desired. A start would be possible immediately. If the freelancer is currently not available, then a start is also possible until April 1.