Web app programming

I require an experienced developer to build a full-stack web application focused on streamlining scheduling and communications for my activity. The app must allow users to view open appointment slots on a calendar interface, reserve times and pay for it. The open slots must have an expiry for booking. It should facilitate one-on-one text consultations between customers and practitioners. A key feature is enabling group chat sessions where a practitioner can chat with multiple people simultaneously. People and practitioners would need to register and be able to switch to different profile (user in the group or manager). Admin controls for user permissions and analytics reporting are essential. Proficiency in modern frameworks is expected. Applicants should demonstrate a solid portfolio of similar appointment booking projects completed on time and on budget. Reliability and excellent communication skills are important as deadlines must be met.