AI Developer - LLM Applications

About the role

REAKTOR'S AWARD-WINNING TECH COMMUNITY IS LOOKING FOR AI DEVELOPERS TO JOIN US IN HELSINKI.

If you thrive on applying cutting-edge AI technologies, building LLM-powered applications, and driving projects through the full software development lifecycle — and you’re passionate about solving real human problems with a holistic approach — we’d love to meet you. Join us to experience a truly collaborative, low-hierarchy environment where your curiosity and ideas can make a real impact.

AS AN AI DEVELOPER AT REAKTOR, YOUR JOB IS TO BE AN EXPERT IN A RANGE OF AI-RELATED SOFTWARE DEVELOPMENT RESPONSIBILITIES SPANNING THE ENTIRE SOFTWARE DEVELOPMENT LIFECYCLE, FROM FRONT-END TO PRODUCTION.

Your daily tasks include:

- Designing and implementing end-to-end LLM-enabled applications from backend architecture to user-facing components, ensuring scalability and maintainability.

- Integrating commercial and open source LLMs (e.g. OpenAI, Anthropic, Meta Llama etc.) into production applications and workflows, using APIs or fine-tuning.

- Working with end-to-end RAG pipelines, including embeddings, vector databases (e.g. PostgreSQL + pgvector, chromaDB, pinecone), robust prompt engineering strategies and guardrails

- Designing and implementing evaluation pipelines to benchmark the model performance and safety

- Collaborating with cross-functional teams, contributing to the development of AI use cases to address complex business challenges

- Working together with the client’s tech and business teams and helping them to pick the right technologies suitable for their needs.

- Delivering the client and the team with world-class technical expertise.

- Developing the agentic software development process and ways of working, to better leverage the use of AI.

- Other software development-related tasks like contributing to the overall software architecture and design, building test automation and debugging problems.

YOU ARE A CURIOUS-MINDED AI DEVELOPER WHO IS COMFORTABLE WORKING WITH LLMS, BACKEND, AND FRONT-END OF AN APPLICATION. ADDITIONALLY, YOU UNDERSTAND THE ROLE OF INFRASTRUCTURE AND UNDERSTAND THE UNDERLYING WORKINGS OF TRANSFORMER-BASED MODELS.

To thrive in this position, you’ll need:

- Experience working with AI software development technologies (LLMs, backend, frontend, ops, and consulting skills) in a production environment.

- Experience in deploying AI applications in cloud environments (Azure, AWS, GCP) with containerization/orchestration (Docker, Kubernetes)

- We don’t have a hard limit on years of experience, but we’ve noticed that some of these competencies take several years to accumulate.

- Foundational knowledge in DevOps, including Continuous Integration (CI), automated deployment, and test automation.

- Know-how on vector databases and databases (e.g., PostgreSQL + pgvector, pgvectorscale, chromaDB, pinecone).