ML Engineer (Scala & Python focus)

Polar Night Software is a software consultancy company based in Łódź working mainly with Nordic clients. We were founded in early 2020 and we are growing. We have a number of good references from Nordic customers and they trust that we deliver quality solutions. 

ML Engineer (Scala & Python focus)

We are looking for a developer, who fits the Polar Night SW team and is interested in working with our team in the long run, not just in one customer project. Your first project would be:

CONTEXT

- Client is investing heavily in AI-powered features across their software product suite for B2B customers
- The application landscape includes multiple AI systems: an LLM-based chatbot with a custom RAG pipeline, a legacy chatbot built in Scala, a high-volume service running self-hosted ML models, and an AI orchestration layer under development
- You will be the primary technical owner of these systems, working in a small autonomous team of 4-5 people
- This is a hands-on role with full ownership from maintenance and troubleshooting through to new feature development (roughly 50-50 balance)

KEY RESPONSIBILITIES

- Maintain and develop the LLM chatbot backend, including RAG pipeline and Azure OpenAI integrations
- Own the Scala/Akka legacy chatbot: read, troubleshoot and handle production issues as needed
- Ensure reliability and continued development of the transcription service processing over a million events per week
- Contribute to the development of an AI orchestration layer that routes requests across different models
- Work independently and take end-to-end ownership of production systems used by paying customers
- Collaborate with product, design and QA in a small cross-functional team

Must-have:

• Solid Scala proficiency, ability to read, maintain and troubleshoot existing codebases

• Strong Python backend development, ideally with FastAPI or similar async frameworks

• Hands-on experience with LLM integrations, RAG pipelines and prompt engineering

• Security-conscious approach to software development

• Ability to seek out information proactively

• Comfortable owning and operating production systems independently
  

Nice-to-have:

• Experience with Apache Pekko / Akka actor framework

• Experience working with self-hosted ML models in production

• Comfortable owning and operating production systems independently

Stack & tools:
- Python
- Scala
- FastAPI
- Akka
- Elasticsearch
- Azure OpenAI
- RabbitMQ
- Celery
- Hugging Face Transformers
- Docker

Fluent English skills will be necessary for the position, cause we’re working only with Nordic and international clients. We have an office in the center of Łódź. You are free to work from the office or pretty much fully remote as long as you are ready to visit your colleagues a few times a year. You need to however live in Poland.

What you can expect from us

What we can offer is a great amount of freedom, responsibility and interesting projects with international customers. Your vision and ideas about developing our culture, community, working methods, recruitments and business in general would be truly welcome and valuable. Low hierarchy, professional & supportive team. 

Salary: 15.000 - 25.500 + VAT (B2B) per month, depending on your experience.

Benefits: 

• Private healthcare (Medicover Premium) for you and your partner/family

• Sports card (MultiSport Plus)

• Flexible working hours

• Possibility to work remotely

• Company integration meetings (activities, dinners and parties) 

We would be more than happy to tell you more about us and opportunities, so don’t hesitate to drop a message! It would be great to talk more just online or even with a cup of coffee or a beer :) !