ML platform engineer in GenAI

Preply; Barcelona; On-site; EUR 100,000 - 140,000; Full time

Benefits offered by this job

Relocation package to Barcelona Hub

Health insurance

Gympass access

Learning & Development budget

Time off for self-development

Equity

Job summary

Preply is powering learners worldwide and seeks a senior Backend/GenAI engineer to architect scalable ML infrastructure in Barcelona. You will design unified gateways, build python APIs, and work across model vendors, with a strong emphasis on reliability, performance, and security.

You will own production systems, implement observability, cost controls, and CI/CD for GenAI workflows, collaborating with security teams and on-call rotations.

Qualifications

• 5+ years designing, building and operating production backend or ML infra.
• Strong Python and API/SDK development experience.
• Hands-on GenAI experience with vector retrieval and external APIs.

Responsibilities

• Architect unified gateway with automated routing and resilient fallbacks.
• Improve system efficiency via dynamic traffic management and caching.
• Establish evaluation mechanisms for precision, stability, and safety.
• Deliver observability with tracing, telemetry, cost analytics, monitoring.
• Standardize prompt engineering with versioning, testing, and CI/CD.
• Collaborate with security/privacy to enforce policies and safe defaults.

Skills

Backend systems

Python

GenAI systems

Distributed tracing

Cloud (AWS)

Observability

APIs/SDKs

On-call rotation

English (C1)

Tools

Metaflow

Databricks

AWS SageMaker

Vector databases

GPU optimization

Job description

Описание:

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.

Задачи:

• 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.

Требования:

• 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;
• Будет плюсом: Familiarity with evaluation suites, prompt management, vector databases, or customized GenAI observability tooling;
• Будет плюсом: Experience with Metaflow, Databricks, or AWS SageMaker;
• Будет плюсом: Knowledge of hosting open-source foundation models, optimizing GPU compute, dynamic scaling, and infrastructure cost controls;
• Будет плюсом: Familiarity with agentic workflows, multi-agent frameworks and tool-use patterns

Условия:

• 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!).