Junior Ai Scientist

Workster; Almada; Hybrid; EUR 60,000 - 90,000; Full time

Benefits offered by this job

Health insurance

Subsidised apartment

Learning budget

Equity potential

Modern hardware

Job summary

Workster, a cutting-edge AI startup, is hiring for an Associate level role in Lisbon with hybrid work and the option for multi-week remote blocks. You will research, prototype, and deploy Agentic LAM features while running LLMs and RAG pipelines.

Strong foundations in linear algebra and Python, plus PyTorch or TensorFlow, are expected. Join a fast-paced team with mentorship from senior AI engineers, exposure to Weights & Biases or MLflow, and opportunities for equity, learning budgets, and

Qualifications

• Strong fundamentals in linear algebra, probability, calculus, or optimisation.
• Python, Jupyter, Git.
• PyTorch or TensorFlow.
• Hugging Face Transformers for simple fine-tuning.
• Vector databases (e.G., FAISS or Qdrant).
• Understanding of evaluation metrics such as accuracy, F1, or perplexity.
• Familiarity with Docker and basic cloud concepts is a plus.
• A proactive, learning-driven mindset.
• No formal degree required—skills, passion, and initiative matter

Responsibilities

• Assist in research, prototyping, and feature development to advance their Agentic LAM from proof-of-concept to production.
• Running and fine-tuning Large Language Models (LLMs).
• Implementing Retrieval-Augmented Generation (RAG) pipelines.
• Preparing and cleaning datasets for training and evaluation.
• Designing and running tests to improve accuracy, safety, and reliability.
• Write clear, maintainable Python code for experiments and prototypes.
• Collaborate closely with senior scientists to learn best practices in AI optimisation, scaling, and evaluation.
• Track experiments and analyse results using tools like Weights & Biases or MLflow.

Skills

Strong fundamentals in linear algebra

Probability

Calculus

Optimization

Python

Jupyter

Git

Proficiency in PyTorch

Proficiency in TensorFlow

Hugging Face Transformers

Vector databases

Understanding evaluation metrics

Docker

Cloud concepts

Tools

PyTorch

TensorFlow

Hugging Face Transformers

Weights & Biases

MLflow

FAISS

Qdrant

Docker

Job description

Overview Workster is partnering with a cutting-edge AI startup on a mission to give models the ability to act autonomously—running code, fixing systems, and analysing data—so humans can focus on strategy and creativity. Their work goes beyond traditional language models, focusing on AI that can perform real, meaningful tasks. If you're excited by the idea of applying advanced AI research to create practical, high-impact solutions, this is a great opportunity to join a small, fast-moving team where your contributions will be seen and valued.

Responsibilities

Assist in research, prototyping, and feature development to advance their Agentic LAM from proof-of-concept to production.

Running and fine-tuning Large Language Models (LLMs).

Implementing Retrieval-Augmented Generation (RAG) pipelines.

Preparing and cleaning datasets for training and evaluation.

Designing and running tests to improve accuracy, safety, and reliability.

Write clear, maintainable Python code for experiments and prototypes.

Collaborate closely with senior scientists to learn best practices in AI optimisation, scaling, and evaluation.

Track experiments and analyse results using tools like Weights & Biases or MLflow.

Qualifications

You don't need to know everything on the list — but you should bring depth in at least one or two areas and the curiosity to learn more. For example:

Strong fundamentals in linear algebra, probability, calculus, or optimisation.

Python, Jupyter, Git.

PyTorch or TensorFlow.

Hugging Face Transformers for simple fine-tuning.

Vector databases (e.G., FAISS or Qdrant).

Understanding of evaluation metrics such as accuracy, F1, or perplexity.

Familiarity with Docker and basic cloud concepts is a plus.

A proactive, learning-driven mindset.

No formal degree required—skills, passion, and initiative matter

The Offer

Hybrid work in Lisbon with the option for multi-week remote blocks.

Competitive salary plus equity potential.

Subsidised apartment if relocating.

Health insurance, modern hardware, and a personal learning budget.

Company-funded travel to global AI conferences and events.

Work directly with experienced AI engineers and researchers, with strong mentorship opportunities.

Fast-paced startup environment with real ownership from day one.

Seniority level Associate

Employment type Full-time

Job function Information Technology

Industries Technology, Information and Media

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