Senior ML Engineer

About the Role: PhantomBuster is a web automation SaaS that allows businesses to grow faster by finding and connecting with ideal customers. We are building agentic AI into the core of our product and need a Senior ML Engineer to set standards, build frameworks, and define our ML infrastructure with a focus on LLM-based and agentic systems.

What You'll Do

• Define and evolve our infrastructure to allow for better ML and AI capabilities, focusing on LLM-based and agentic systems.
• Contribute to the development of our agentic AI framework powered by AWS Bedrock for internal tools and customer-facing features.
• Identify, source, and pre-process datasets (cleaning, feature engineering) to tune models and power retrieval pipelines.
• Train, evaluate, and deploy both LLM-based systems and traditional machine learning models into production.
• Support the integration of LLMs, including fine-tuning, prompt tuning, and retrieval-augmented generation (RAG).

What You Bring

• 5+ years of experience as an ML Engineer, AI Engineer, or Software Engineer with a strong AI focus.
• Hands-on experience building AI agents using frameworks such as LangChain or Amazon Bedrock AgentCore.
• Strong understanding of LLM-based systems: prompt engineering, agent orchestration, tool use, and multi-agent workflows.
• Proficiency in Python and standard data libraries (Pandas, NumPy, etc.), along with experience in cloud platforms (AWS).
• Bonus: Experience with conversational chat agents, MLOps (MLflow, Airflow), and open-source AI contributions.

Benefits

• Fully remote working environment with real ownership to define how agentic AI is built.
• Home office budget up to €1500 and a €40/month remote work allowance.
• Flexible working hours, €70/month entertainment benefit, and a Book Allowance program.
• 100% remote work flexibility within France, Spain, or Portugal.