Senior Software Engineer (Python, LLM, RAG) Europe Our mission Constructor’s mission is to enable all educational organisations to provide high-quality digital education to 10x people with 10x efficiency. With strong expertise in machine intelligence and data science, Constructor’s all-in-one platform for education and research addresses today’s pressing educational challenges: access inequality, tech clutter, and low engagement of students. Our headquarters is located in 🇨🇭Switzerland, and we also have legal entities in 🇩🇪Germany, 🇧🇬Bulgaria, 🇷🇸Serbia, and 🇸🇬Singapore Please send your resume in English only. We don't offer visa sponsorship to Switzerland, Singapore, or Germany. DUTIES & RESPONSIBILITIES: Design, develop, and maintain backend services and APIs, applying microservice architecture patterns (synchronous and asynchronous communication). Drive the platform's architecture, scalability, performance, reliability, and security. Participate in code reviews and provide feedback to peers. Write robust, maintainable, and well-tested code (pytest). QUALIFICATION & EXPERIENCE: 5+ years of professional backend development experience. Strong knowledge of FastAPI (or similar modern frameworks) and asynchronous programming in Python. Deep understanding of microservices and communication patterns (sync/async, event-driven). Solid knowledge of PostgreSQL (indexes, transactions, locking). Experience with RabbitMQ (messaging patterns, delivery guarantees). Familiarity with CI/CD pipelines. Solid understanding of programming principles (e.g., SOLID, dependency injection, clean architecture). Problem‑solving skills and autonomy. >English level B2 or higher. Nice-to-Have: Hands‑on experience deploying and running applications in Kubernetes (Helm is a plus). Exposure to vector databases (e.g., Qdrant). Experience integrating with LLM APIs (OpenAI, Anthropic). Familiarity with LangChain/LangGraph and RAG architectures. What We Offer 💻 Choice of work equipment (e.g., laptop, monitor, etc.) ⏰ Flexible schedule (we usually work between 09:00/10:00 and 18:00/19:00 CET or EET) 🧑💻 Remote work in locations without our offices Hybrid work in locations with offices (2 days in‑office, 3 days remote): 🇧🇬 Sofia: 59 G. M. Dimitrov Blvd., NV Tower, 8th floor, 1700 🇷🇸 Belgrade: Makedonska 12, 11000 Belgrade, Serbia Constructor fosters equal opportunity for people of all backgrounds and identities. We are led by a gender‑balanced board committed to building a diverse and inclusive organisation where everyone can become their best self. We do not discriminate based on age, disability, gender identity, sexual orientation, ethnicity, race, religion or belief, parental and family status, or other protected characteristics. We welcome applications from women, men and non‑binary candidates of all ethnicities and socio‑economic backgrounds. We encourage people belonging to under‑represented groups to apply. #J-18808-Ljbffr