Senior AI Engineer: LLM Systems & RAG Pipelines

Sii Poland; Kraków; On-site; PLN 260,000 - 380,000; Full time

Benefits offered by this job

Great work environment

Medical care

Profit sharing

Training programs

Office amenities

Job summary

Sii Poland is building a new AI team in Kraków to design and deliver production-grade AI systems powered by LLMs in a regulated environment. You will work on end-to-end pipelines, retrieval, and evaluation, leveraging LangChain, LangGraph, and LlamaIndex, with a focus on robust, scalable cloud infrastructure.

The roles require 5+ years of software/AI experience, strong Python, and hands-on experience with LLM frameworks.

Qualifications

• 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.

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 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.

Skills

Python

LLM frameworks

Vector databases

RAG pipelines

SQL & cloud data

English fluency

Poland resident

Tools

LangChain

LangGraph

LlamaIndex

Job description

Sii Poland is building a new AI team in Kraków to design and deliver production-grade AI systems powered by LLMs in a regulated environment. You will work on end-to-end pipelines, retrieval, and evaluation, leveraging LangChain, LangGraph, and LlamaIndex, with a focus on robust, scalable cloud infrastructure.

The roles require 5+ years of software/AI experience, strong Python, and hands-on experience with LLM frameworks.