Senior AI Engineer – Agentic Workflows, RAG & Automation

Billennium; Polska; Hybrid; PLN 170,000 - 210,000; Full time

Benefits offered by this job

Comprehensive benefits

Remote/hybrid options

Career growth

Global collaboration

Innovative environment

Engaging community

Team-building events

Welcome pack

Job summary

Billennium is seeking a Senior AI Engineer to design and deliver production-grade AI solutions for enterprise environments. You will transform AI concepts into reliable, scalable systems, including AI assistants, agentic workflows and RAG-based applications.

The role combines advanced LLM engineering with software best practices, system integration and production readiness, working across data sources and business systems while focusing on evaluation, observability and cost optimization.

Qualifications

• 5+ years of software/AI engineering experience in production
• Strong Python programming skills and backend/API experience
• Proven track record deploying LLM-based apps in production environments
• Experience with RAG architectures, vector stores and retrieval
• Familiarity with LangGraph/LangChain or similar orchestration tools
• Experience with Microsoft Copilot / Copilot Studio integration
• Knowledge of LLM evaluation, observability and regression testing
• CI/CD, automated testing and version control practices
• Ability to design modular, reusable AI components

Responsibilities

• Design, develop and deploy production-grade AI assistants and workflows
• Build and optimize RAG pipelines and vector-based retrieval systems
• Develop agentic workflows using LangGraph, LangChain or equivalents
• Create backend services and APIs with Python and FastAPI
• Integrate AI solutions with enterprise data sources and systems
• Implement evaluation, tracing and regression testing for LLM apps
• Monitor performance, latency and cost of AI solutions
• Contribute reusable AI components and engineering patterns
• Support production deployments with CI/CD and cloud-native tech

Skills

5+ years

Python

FastAPI

LLM-based applications

RAG architectures

LangGraph

LangChain

Copilot integration

CI/CD

Observability

Tools

LangGraph

LangChain

Microsoft Copilot

Job description

Billennium is a global technology company with over 20 years of experience, committed to innovation and empowering businesses. As an employer, we offer a supportive, growth-focused environment where collaboration and creativity thrive. Join us to shape the future of technology together!

We are looking for an experienced Senior AI Engineer to design and deliver production-grade AI solutions for enterprise environments.

This role is focused on transforming AI concepts and business requirements into reliable, scalable solutions, including AI assistants, agentic workflows, RAG-based applications and workflow automation. It combines advanced LLM engineering with strong software engineering practices, system integration and production readiness.

Key Responsibilities

• Design, develop and deploy production-grade AI assistants, agents and workflow automation solutions
• Build and optimize Retrieval-Augmented Generation (RAG) pipelines and vector-based retrieval mechanisms
• Develop agentic workflows using LangGraph, LangChain or equivalent orchestration frameworks
• Design and develop backend services and APIs using Python and FastAPI
• Integrate AI solutions with Microsoft Copilot and Copilot Studio
• Connect AI applications with enterprise data sources and business systems
• Implement evaluation frameworks, observability, tracing and regression testing for LLM-based applications
• Monitor and optimize solution quality, performance, latency and cost
• Build reusable AI components and engineering patterns that can be applied across multiple projects
• Support production deployments through CI/CD, containerization and cloud-native technologies
• Ensure solutions meet enterprise standards for reliability, maintainability and scalability

Requirements

• 5+ years of experience in software engineering, AI engineering or a related technical field
• Strong hands‑on programming skills in Python
• Commercial experience in backend and API development, preferably using FastAPI
• Proven experience developing and deploying LLM‑based applications in production environments
• Practical knowledge of RAG architectures, vector databases and information retrieval
• Experience with LangGraph, LangChain or similar agent orchestration frameworks
• Experience with Microsoft Copilot / Copilot Studio integration
• Knowledge of LLM evaluation approaches, observability and regression testing
• Experience with software engineering best practices, including CI/CD, automated testing and version control
• Understanding of production considerations such as monitoring, security, performance, latency and cost optimization
• Ability to design modular and reusable technical components

What We Value

We are particularly interested in candidates who can demonstrate experience in taking AI solutions beyond the proof‑of‑concept stage and into production.

Examples may include:

• Enterprise RAG assistants integrated with internal data sources
• Agentic solutions automating multi‑step business processes
• AI‑based document analysis and task‑routing workflows
• LLM platforms incorporating tracing, evaluation and prompt or version management
• Solutions with measurable improvements in quality, efficiency, adoption, latency or operating costs

Experience supported by working solutions, architecture diagrams, evaluation results, telemetry or reusable technical components will be highly valued.

Perks and benefits:

• Comprehensive benefits - enjoy Udemy for Business, private medical care, Multisport card, veterinary package, language lessons, and shopping vouchers.
• Flexibility - adaptable working hours and remote/hybrid work options to suit your lifestyle & location.
• Career growth - access opportunities for professional development and learning, including perks related to our official partnerships with global IT giants: Microsoft, AWS, Snowflake, Salesforce & more.
• Global collaboration - work with a diverse, international team.
• Innovative environment - be part of a forward‑thinking and growth‑oriented workplace.
• Engaging community – Work with passionate professionals and participate in team‑building events, hackathons, and CSR initiatives to make an impact beyond work.
• Team‑building events including our company tradition (annual company event in Mazury).
• A pleasant surprise to start your journey with us in the form of a welcome pack.

Recruitment process:

• HR call
• Technical Interview
• Interview with the dedicated Client