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90,000+ live jobsSenior ML Engineer
Hybrid in Barcelona·Full-time·Added 2 days ago (last checked 4 Nov)
10 open roles
Our summary
- Work mode
- Hybrid, Barcelona
- Contract
- Permanent, full-time hours
- English
- Required
- Experience
- Senior level




Visa options
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Skills
Pay & benefits
What you'll get
We offer a comprehensive pay and benefits package designed to stay competitive in the market, support your wellbeing, and recognise your contribution to our success. Our approach is underpinned by a pay-for-performance belief in rewarding individual impact. Your specific compensation package will be determined by factors such as your skills, experience, qualifications, and location.
Depending on your role and location, you may be eligible for annual bonuses and incentives, health and wellbeing benefits, paid time off, retirement plans, insurance coverage, and other local or statutory benefits.
Specific details about compensation and benefits for this position will be discussed during the recruitment process.
The role
Product Madness owns the mobile gaming industry by developing engaging, ground-breaking gaming experiences. We value data's role in improving player experiences and guiding strategic business decisions. Join our innovative, collaborative team and contribute to crafting the future of mobile gaming. As a Senior ML Engineer at Aristocrat, you will work with modern technology that transforms the gaming experience for millions of players. This role plays a vital part in our mission to provide personalized and outstanding gaming experiences through sophisticated ML and AI solutions. If you are driven and passionate about employing technology to bring significant change, this opportunity is for you!
What you'll do
- Develop production ML solutions: Build, implement, train, evaluate, and optimize machine learning models for prediction, recommendation, personalization, and decision support.
- Build AI applications: Construct and blend LLM-powered applications, retrieval-augmented generation (RAG) systems, and agentic workflows into internal tools and business processes.
- Engineer end-to-end solutions: Translate ML/AI requirements into reliable software components, services, and APIs, ensuring maintainability, performance, and scalability.
- Analyze ML and AI systems: Formulate evaluation techniques, validate model quality, pinpoint failure modes, and uphold robustness, safety, and reliability of ML/AI outputs.
- Integrate models into production: Work alongside MLOps Engineers to deploy, monitor, and maintain ML/AI solutions, ensuring smooth integration with existing platforms and applications.
- Enhance performance: Increase model inference speed, resource management, latency reduction, and scalability of ML/AI applications.
- Apply engineering guidelines: Write clean, well-tested, maintainable Python code; implement automated testing, code reviews, documentation, and reliable error handling.
- Work with complex data: Retrieve, integrate, validate, and prepare data from multiple sources to support model training, inference, and evaluation.
- Collaborate across teams: Work closely with Data Scientists, MLOps Engineers, Data Engineers, and product partners to transform business needs into practical data-driven intelligence solutions.
- Contribute to technical excellence: Participate in architecture discussions, mentor less experienced engineers, and help improve development standards and engineering practices.
What We're Looking For
- Strong software engineering expertise: Expert-level Python programming, software build, automated testing, debugging, version control, and collaborative development practices.
- Machine learning: Hands-on experience developing, training, evaluating, and optimizing supervised learning models using frameworks such as scikit-learn, PyTorch, TensorFlow, or similar.
- Generative AI: Practical experience developing applications using LLMs, including timely input crafting, structured outputs, RAG, tool calling, and agentic workflows.
- ML/AI evaluation: Experience crafting evaluation pipelines, measuring model performance, identifying failure modes, and validating AI outputs.
- ML specialization: Solid hands-on experience within one or more fields including recommender systems, reinforcement learning, time-series modeling, unsupervised learning, or causal/Bayesian modeling.
- AI specialization: Background in at least one domain such as LLM/NLP applications, agentic workflows, or computer vision.
- Data engineering fundamentals: Strong SQL skills, experience integrating data through APIs and other interfaces, and understanding of data quality and preprocessing.
- Production ML: Experience with model deployment, inference services, monitoring, model versioning, and ML lifecycle management.
- Cloud & infrastructure: Solid understanding of cloud platforms (e.g., GCP, AWS, Azure), containers, CI/CD pipelines, and ML development environments.
- Performance engineering: Experience optimizing software performance, inference latency, or resource utilization.
If you're passionate about using data science to build outstanding gaming experiences and ready to lead data products to success, we want to hear from you. Join Product Madness and help develop the future of mobile gaming!
Important Information for Applicants
- CV Language: Please submit your CV in English.
- Hybrid Working Policy: This role follows a hybrid working model, requiring attendance at our Barcelona office 3 days per week.
This job description may have been reviewed and enhanced using AI-assisted tools to improve clarity, consistency, and inclusivity. All final content, role requirements and hiring decisions remain subject to human review and approval by Aristocrat.
About Aristocrat
Aristocrat is a global leader in the gaming and technology industry, headquartered in Sydney, Australia. The company designs, develops, and distributes gaming machines, casino management systems, and digital gaming content, operating across land-based and online gaming sectors. With a workforce of over 10,000 employees worldwide, Aristocrat is known for its iconic gaming products and innovative technology solutions that power casinos and gaming venues across the globe.
In Spain, Aristocrat has established a presence, with offices in Madrid and Barcelona, focusing on digital gaming and technology development. The company's Spanish operations are part of its global network, offering opportunities for international professionals in areas such as engineering, data science, and creative design. Aristocrat values innovation and collaboration, providing a dynamic work environment that supports career growth and cross-cultural exchange, making it an attractive employer for those looking to work in the gaming industry in Europe.
- Industry
- Gaming
- Founded
- 1953
- Employees
- 10,000–50,000
- Headquarters
- Sydney, Australia
- In Spain
- Madrid, Barcelona
Good to know if you are moving
- Aristocrat has a global presence with offices in over 30 countries, offering international mobility opportunities.
- The company is a leader in the gaming industry, providing a stable and innovative work environment.
- Spain offices focus on digital gaming and technology, with roles in engineering, data, and creative design.
- Aristocrat supports flexible working arrangements and a collaborative culture.
- The company offers competitive compensation and benefits packages for international hires.
Location
Aristocrat · Barcelona
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