AI Engineer – LLM / Agentic Systems (f/m/x)

Sii Poland; Łódź; On-site; PLN 210,000 - 320,000; Full time

Benefits offered by this job

Great Place to Work

Profit sharing

Medical care

Centre of internal trainings

Learning from experts

Job summary

Sii Poland is building a new AI team in Łódź to design and deliver production-grade AI systems powered by LLMs within a regulated environment. You will contribute to data pipelines, RAG workflows, and cloud infrastructure while collaborating with Data Science teams.

The roles focus on hands-on development of AI solutions, model integration, and rigorous evaluation in healthcare and data-driven marketing domains. English fluency required and Poland residency is expected.

Qualifications

• Minimum 5 years of commercial software development or AI/ML engineering experience.
• Strong Python skills with solid software engineering practices (modular design, testing, code reviews).
• Hands-on experience with LLM frameworks such as LangChain, LangGraph, or LlamaIndex.
• Experience with vector databases (Pinecone, Weaviate, pgvector, OpenSearch).
• Experience building RAG pipelines and working with unstructured data.
• Experience with SQL and cloud-based data systems.
• Availability to start within 2 weeks for fast project kickoff; Fluent English; Residing in Poland.

Responsibilities

• Design and develop production-ready AI systems based on LLMs and agent-based workflows.
• Build and maintain data pipelines for retrieval, orchestration, and evaluation.
• Implement solutions using LangChain, LangGraph, LlamaIndex, or custom approaches.
• Develop and optimize RAG pipelines (chunking, embedding, retrieval, reranking).
• Integrate LLM models (OpenAI and open-source) and support model selection decisions.
• Collaborate with Data Science teams to productionize ML models.
• Build evaluation frameworks (metrics, test sets, regression tests) and monitor system performance.
• Create and maintain scalable AI infrastructure in a cloud environment.

Skills

5+ years experience

Python

English fluency

SQL

Cloud data systems

Tools

LangChain

LangGraph

LlamaIndex

Pinecone

Weaviate

pgvector

OpenSearch

Job description

We are building a new AI team within a project in the digital healthcare / data-driven marketing domain. We are looking for both a Tech Lead and Senior Engineers who will work together as one cohesive team.

The role focuses on designing and delivering production-grade AI systems powered by LLMs in a real-world, regulated environment.

Your tasks

• Design and develop production-ready AI systems based on LLMs and agent-based workflows
• Build and maintain data pipelines for retrieval, orchestration, and evaluation
• Implement solutions using frameworks such as LangChain, LangGraph, LlamaIndex, or custom approaches
• Develop and optimize RAG pipelines (chunking, embedding, retrieval, reranking)
• Integrate LLM models (OpenAI and open-source) and support model selection decisions
• Collaborate with Data Science teams to productionize ML models
• Build evaluation frameworks (metrics, test sets, regression tests) and monitor system performance
• Create and maintain scalable AI infrastructure in a cloud environment

Requirements

• Minimum 5 years of commercial experience in software development or AI/ML engineering
• Strong Python skills with solid software engineering practices (modular design, testing, code reviews)
• Hands‑on experience with LLM frameworks such as LangChain, LangGraph, or LlamaIndex
• Experience with vector databases (e.g., Pinecone, Weaviate, pgvector, OpenSearch)
• Practical experience building RAG pipelines and working with unstructured data
• Experience working with SQL and cloud-based data systems
• Availability to start within 2 weeks due to a fast project kickoff
• Fluency in English
• Residing in Poland required

Sii ensures that all hiring decisions are made solely on the basis of qualifications and competence. We are committed to equal and fair treatment of all, regardless of legally protected characteristics. At Sii, we promote a diverse and inclusive work environment, in full compliance with applicable anti-discrimination laws.

Benefits For You

• Great Place to Work
• Solid financial situation
• Contracts with the biggest brands
• Centre of internal trainings
• Many experts you can learn from
• Open and accessible management team
• Profit sharing
• Passion Sponsorship program
• Regular integration events and trips
• Comfortable and well-equipped offices
• MySii app
• Medical care