Principal Backend Engineer (AI)

Location: Remote from Serbia; core working hours are GMT+3.

Salary: From $6,000 net per month.

Company

An online English-learning platform for children serving more than 100,000 students and working with over 4,000 teachers across 15+ countries.

What you will do

• Own backend architectural standards and review major technical decisions across engineering teams.
• Define the transition path from a large monolith toward a modular and service-oriented architecture.
• Create service blueprints covering project structure, API conventions, event-driven architecture, testing, observability, and deployment.
• Work with Product and AI/Data teams to turn AI-driven learning concepts into reliable backend systems.
• Implement production code, core backend components, refactorings, proof-of-concepts, platform improvements, and critical product features.
• Balance long-term architectural quality with product delivery speed and business priorities.

Requirements

• 7+ years of backend engineering experience with deep hands-on expertise in Python.
• Production experience with FastAPI, SQLAlchemy, Celery, PostgreSQL, and Redis.
• Strong understanding of distributed systems, microservices, modular monoliths, event-driven architecture, and service boundaries.
• Practical knowledge of API design, testing, observability, security, CI/CD, documentation, and code quality.
• Experience with AWS messaging and event services, including SQS, SNS, and EventBridge.
• Fluent English and availability to work core hours aligned with GMT+3.

Nice to have

• Experience building or integrating backend systems around LLMs or AI products.
• Experience in EdTech, e-commerce, marketplaces, or high-scale consumer platforms.
• Experience in startups or high-growth environments.

Culture & Benefits

• Fully remote work with GMT+3 core hours.
• Opportunity to shape AI-driven education products.
• Unlimited holidays.
• Bonuses and stock options.