ML platform engineer in GenAI

We power people’s progress. At Preply, we’re all about creating life-changing learning experiences. We help people discover the magic of the perfect tutor, craft a personalised learning journey, and stay motivated to keep growing. Our approach is human-led, tech-enabled - and it’s creating real impact. We’ve just reached unicorn status with a $150M Series D, accelerating our vision to transform education through human-led, AI-enhanced learning.

• Architect unified gateway with automated routing, quota controls, and resilient fallback systems across model vendors.
• Drive system efficiency and low latency via dynamic traffic management, response caching, token budgeting, and cost allocation controls.
• Establish robust evaluation mechanisms to guarantee high precision, stability, and safety in model outputs.
• Deliver system observability, providing deep tracing, performance telemetry, cost analytics, continuous monitoring, and alerting across GenAI lifecycles.
• Standardize prompt engineering workflows with automated versioning, automated testing, governance, and CI/CD integrations for production delivery.
• Embed platform guardrails alongside Security and Privacy experts to enforce policies, and safe production defaults automatically.
• Maintain sustainable incident response, blameless postmortems, and comprehensive monitoring for GenAI stacks.

• Proven track record (5+ years) designing, building and operating backend services or ML infrastructure handling production traffic.
• Strong Python skills and experience building developer-facing APIs/SDKs or shared libraries
• Practical experience with GenAI systems, including vector retrieval, external provider APIs, and common issues.
• AI Expertise: You're a forefront user of Agentic AI. You're able to bring hands-on experience and start influencing the team beyond code generation; reserving judgment for architecture, business logic, and security, using AI as a thought partner and being able to set up quality gates and safety nets to enhance existing engineering workflows and propose AI-native alternatives.
• Sound knowledge of distributed systems, including high availability, concurrency, caching and rate limiting.
• Experience with at least one major public cloud, its services and infrastructure (preferably AWS).
• Hands-on experience with distributed tracing, system telemetry, SLOs, and incident triage.
• Strong communication skills and at least C1 English level, plus willingness to join a paid on-call rotation.
• Будет плюсом: Experience operating AI gateways or scalable model serving infrastructure; Familiarity with evaluation suites, prompt management, vector databases, or customized GenAI observability tooling; Experience with Metaflow, Databricks, or AWS SageMaker; Knowledge of hosting open-source foundation models, optimizing GPU compute, dynamic scaling, and infrastructure cost controls; Familiarity with agentic workflows, multi-agent frameworks and tool-use patterns

• An open, collaborative, dynamic, and diverse culture;
• A generous monthly allowance for lessons on Preply.com, Learning & Development budget, and time off for your self-development;
• A competitive financial package with equity, leave allowance and health insurance;
• Not in Barcelona? We offer an attractive relocation package to join us in our Preply Barcelona Hub
• Access to free mental health support platforms;
• Access to Gympass-partnered wellness and gym centers throughout Spain to promote and support well-being and physical health;
• The opportunity to unlock the potential of learners and tutors through language learning and teaching in 175 countries (and counting!).