Principal Backend Engineer (Architect Track) - Remote

Location: Beograd, Serbia Workplace: remote Novakid is an online English platform for kids — 100,000+ students, 2,500+ teachers, 15+ countries. Live classes run around the clock across time zones, which sets the technical bar: low latency, high availability, and a backend that holds up at real scale. We’ve built a working platform. The next chapter is making deliberate architectural choices about how it should evolve. The role We’re hiring a Principal Backend Engineer to take ownership of backend architecture as a hands-on technical leader. No direct reports. About half your time is in the code — reference implementations, critical components, refactors. The other half is the harder work: deciding what to build, what to buy, what to defer, and why. Our backend today is a Python core (FastAPI, SQLAlchemy, Celery, Postgres, Redis), surrounded by services and event-driven flows, with a growing AI layer. It runs primarily on AWS, with GCP for data and AI workloads. There are real architectural questions to answer: how to evolve the monolith, how to set service boundaries, how to design for geo-distribution as we grow, and how to integrate AI without accumulating debt. We’re looking for someone who treats those questions seriously — researches before deciding, thinks in tradeoffs, writes things down. What you’ll work on Backend architecture standards and major technical decisions across teams The path from monolith toward a more modular, service-oriented backend Service blueprints: API conventions, EDA patterns, testing, observability, deployment Cloud architecture across AWS (primary) and GCP, including multi-region and geo-distributed designs High-load, real-time systems: live class infrastructure, latency budgets, caching, capacity Buy vs. build vs. assemble — knowing when a managed service, a no-code tool (Retool, n8n), or an agentic-coding POC (Claude Code, Cursor) is the right call, and when it isn’t Production code: components, refactors, POCs, and selected product-critical features What we’re looking for 7+ years of backend engineering, deeply hands-on in Python Production experience with FastAPI, SQLAlchemy, Celery, Postgres, Redis Strong AWS architecture experience (EKS, Lambda, RDS, SQS/SNS/EventBridge, and so on); working knowledge of GCP a plus Experience designing high-load, latency-sensitive, and geo-distributed systems Pragmatic judgment on buy vs. build vs. assemble — managed services, no-code, and agentic tooling as first-class options, not shortcuts A deliberate working style: you research, weigh tradeoffs, document decisions, and explain them clearly to engineers and non-engineers alike Nice to have LLM integrations in production (OpenAI, Anthropic, Google AI) — evaluation, cost, reliability Active use of agentic coding tools (Claude Code, Cursor) as part of how you ship EdTech or other high-scale consumer platforms Stack Python · FastAPI · SQLAlchemy · Celery · Postgres · Redis · Kubernetes (EKS, GKE) · AWS · GCP · SQS/SNS/EventBridge · Pub/Sub · OpenAI · Anthropic · Google AI What we  offer… Fully remote work (core hours GMT+3). A chance to shape the future of AI-driven education. A fun, dynamic team that loves building innovative products.Unlimited holidays – because we trust you to deliver. Bonuses and stock options – we grow together.