Senior Software Engineer (React)

Senior Software Engineer We are seeking a Senior Software Engineer to join an established product development team and build, enhance, and maintain proprietary software across the full stack. You’ll collaborate closely with engineering, QA, UX, and product teams to deliver reliable, high-performing applications for a growing resale technology platform. Key Responsibilities Develop new features, enhancements, and fixes across the software stack. Build and maintain applications spanning point-of-sale, product appraisal, and inventory management systems. Write unit, integration, and end-to-end tests while maintaining high software quality. Improve application performance, reliability, and scalability. Troubleshoot production issues and support critical software incidents as needed. Contribute to development and release processes and the Shape Up methodology. Mentor engineers and promote strong collaboration, code quality, and engineering practices. Qualifications 6+ years of professional experience building web applications. Strong experience with modern backend languages and frameworks. Significant experience with modern frontend frameworks and API development. Strong communication, problem-solving, and attention to detail. Ability to independently produce high-quality code without relying on LLMs. Technology Stack Frontend: React, TypeScript, MobX Backend: C#/.NET, Entity Framework Core Database: PostgreSQL, Redis, ClickHouse Testing: Unit, integration, and Playwright Platform: DigitalOcean, Docker, Linux, Balena/IoT Observability: OpenTelemetry, OpenObserve, RUM DevOps & Version Control: GitHub, Forgejo, Docker Hub