Senior Back-End Developer (Health & Fitness app) | Partner

About the Position

We, Boosta - an IT holding company, create, scale, and invest in digital businesses with global potential. Founded in 2014, we have over 700 specialists and 15+ business units. We are looking for a Senior Back-End Developer to join our partner team responsible for developing and scaling backend systems for mobile and web products.

Responsibilities7

• Design and maintain backend architecture for mobile products, admin panels, and internal services.
• Develop and scale REST APIs, integrations with external services, payment platforms, and webhooks.
• Design data structures, manage migrations, optimize queries, and improve database performance.
• Ensure reliability and scalability of the system: performance, fault tolerance, monitoring, logging, and alerts.
• Implement and maintain secure authentication and authorization mechanisms (JWT, OAuth).
• Collaborate with product and engineering teams to launch and scale new features.
• Improve technical documentation and system architecture.

Requirements10

• 4+ years of commercial experience as a Back-End Developer.
• Strong practical experience with Node.js and TypeScript in production products.
• Experience with PostgreSQL, MongoDB, and Redis.
• Proven experience building scalable and reliable backend systems.
• Experience developing REST APIs, integrations, and working with webhooks.
• Deep understanding of authentication and authorization (JWT, OAuth).
• Experience with AWS or other cloud platforms.
• Experience in production environments: logging, monitoring, incident handling.
• Ability to take responsibility and deliver end-to-end solutions.
• Experience collaborating with cross-functional teams.

Benefits4

• Regular master classes (from hard skills to life hacks), sessions with our leaders and external experts, learning budget for courses and conferences.
• Remote work with trust — 10:00-18:00 (Kyiv time), then manage your time independently.
• Fast and transparent career growth, internal candidates are always prioritized.
• Wellbeing - 2 additional days per month for recovery, optional weekly meditations, 14 paid vacation days and paid sick leave.