Data scientist - ai engineer | mid

Job criteria

ABOUT THE OPPORTUNITY

We are looking for a Data Scientist - AI Engineer to support AI and machine learning initiatives in the financial services sector, with a hybrid working model requiring regular presence in Lisbon. This role focuses on developing, deploying and optimizing AI solutions, including Generative AI, LLM-based applications, RAG architectures and agentic AI capabilities.

WHAT YOU WILL DO

• Design, develop and deploy machine learning models and AI solutions aligned with business and technical requirements.
• Fine-tune, extend and integrate Large Language Models, including open-source and commercial models.
• Implement Retrieval-Augmented Generation approaches to improve model accuracy, efficiency and contextualization.
• Develop agentic AI solutions using memory, storage, state management, file system integration, tools, servers, gateways and communication protocols.
• Perform exploratory data analysis and feature engineering to improve model performance and reliability.
• Apply traditional machine learning methods, including decision trees, support vector machines, clustering and neural networks.
• Collaborate with data engineers, product teams and stakeholders to deliver robust, scalable and maintainable AI solutions.
• Validate, test and document AI solutions to support quality, reproducibility and knowledge sharing.

WHAT WE ARE LOOKING FOR

• Bachelor’s or Master’s degree in Computer Science, Data Science, Machine Learning or a related field.
• More than 3 years of hands-on experience in machine learning and AI development.
• Practical experience developing and deploying agentic AI solutions.
• Strong analytical thinking, problem-solving capability and attention to delivery quality.
• Ability to communicate effectively with technical and non-technical stakeholders.
• Collaborative, responsible and solution-oriented working style.
• Professional working proficiency in English at C1 level or equivalent.
• Willingness to learn French.

TECHNICAL SKILLS

• Python
• TensorFlow
• PyTorch
• Hugging Face
• Large Language Models
• Generative AI
• Retrieval-Augmented Generation
• Vector databases
• Natural Language Processing
• Agentic AI architectures
• Agent memory, storage and state management
• MCP servers, tools, gateways and protocols
• Agentic communication protocols, including A2A and ACP
• Traditional machine learning methods, including decision trees, support vector machines, clustering and neural networks
• Cloud platforms for AI and machine learning deployments, including GCP, AWS or Azure
• MLOps practices and tools
• Model testing, validation and technical documentation

NICE TO HAVE

• Knowledge of reinforcement learning from human feedback.
• Strong experience with Generative AI model training, fine-tuning and deployment.
• Understanding of ethical AI principles and model interpretability.
• Professional working proficiency in French.

COMPENSATION TRANSPARENCY

Base salary range: EUR 20 000 - EUR 32 000 gross/year

Total compensation: up to EUR 42 000/year

The salary range is based on objective and gender-neutral criteria, including required competencies, professional experience, level of responsibility and role requirements. Final compensation will be determined according to the candidate's profile and position requirements.

WHAT WE OFFER

• Private health insurance from day one, with no waiting periods and optional family extension.
• Confidential mental health support through dedicated psychological support, content and live sessions.
• Continuous learning, training and certification support throughout your journey.
• Flexibility whenever the role and context allow it, supporting sustainable performance and daily balance.
• Childcare vouchers and practical family support measures.
• Team moments, shared milestones and leadership presence when it matters most.
• Upskilling opportunities in quality management, information security, AI governance and cybersecurity best practices.

EQUAL OPPORTUNITY

Hexa is committed to equal opportunity and inclusive recruitment practices. We value diverse backgrounds, perspectives and experiences, in line with the principles of the Portuguese Diversity Charter.

HEXA LIFE

At Hexa, we are all Builders. We work with honesty, mutual support and agility, building projects, solutions and professional relationships with responsibility and purpose. You will join a collaborative environment where people are encouraged to contribute, improve and grow together.