Senior Full Stack Engineer (B2B - Warsaw)

Location: Warsaw, Poland — Onsite (4 days on-site) Contract: B2B · 25–40 k PLN net / month + RSUs     The AI-powered OS for beauty, wellness and self-care Fresha is the operating system for the global beauty, wellness and self-care industry, connecting and powering everything from salons and barbers to spas, medspas, fitness studios and health practices. Marketplace + SaaS platform + Fintech   Fresha is the leading AI operating system trusted by millions of consumers and businesses worldwide. Fresha is used by 130,000+ businesses and 450,000+ stylists and professionals worldwide, processing over 1 billion appointments to date. Empowering businesses with an all-in-one platform for bookings, point-of-sale, marketing, and more, while connecting consumers to local services. Your Impact as a Full Stack Engineer   At Fresha, we believe AI is a force multiplier for feature delivery, not just a coding assistant. We provide every engineer with top-tier tooling (Claude, GitHub Copilot, Cursor) to strip away technical toil—so you can focus your energy on shipping high-impact product features. We value engineers who know how to leverage these tools to drive momentum within our 6-week cycles, accelerating the journey from concept to code while maintaining the deep technical judgment to verify, secure, and own the final user experience.    Are you ready to make a significant impact in a fast-paced, autonomous environment? We're seeking an exceptional Backend Engineer to join our cross-functional product team in Warsaw.   What You'll Do:   * Collaborate closely with Product, Design, Frontend, Infrastructure, and Mobile engineers to take features from discovery to rollout and beyond. * Be responsible for features from discovery to observability: technical design, implementation, testing, and rollout. * Design, build, and maintain efficient, scalable, and reliable Ruby/Elixir code. * Work with a polyglot stack (Ruby, Elixir, GraphQL, TypeScript, gRPC) and modern messaging systems (Kafka). * Operate within a Kubernetes-driven environment as we continue moving to a microservice architecture. * Embrace Domain-Driven Design to build high-quality, impactful products from inception to delivery.   To foster a collaborative environment that thrives on face-to-face interactions and teamwork, all Fresha employees work from the office four days per week, with the flexibility to work remotely on Wednesday each week. Warsaw: 20th Floor, Aleje Jerozolimskie 81, 02-001 Warsaw, Poland