Hello Retail
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Development & R&D

Senior Data Engineer

Copenhagen, Denmark Full-time Posted March 6, 2026

About the role

At Hello Retail we build the intelligence layer behind modern ecommerce.

Our platform turns raw product and behavioral data into real-time decisions across search, recommendations, and AI agents. The core of this is our Product Intelligence engine – a system that understands products, relationships and buying patterns based on large-scale product data.

We are now looking for a Senior Data Engineer to help scale the infrastructure powering these decisions.

This is not a reporting or BI role. You will build production systems that directly affect revenue for thousands of webshops.

What you will work on

You will design and operate the data backbone that enables our agents across our solutions.

Typical projects:

  • Large-scale product ingestion pipelines
  • Event processing & enrichment
  • Feature generation for ML systems
  • Real-time decision data models
  • High-throughput service performance
  • Reliability & observability of distributed systems

You will work closely with product, ML and other engineers to make intelligent decisions possible.

Tech stack

We value strong engineering fundamentals over exact tools – but relevant experience matters.

Core

  • Python (primary language)
  • MongoDB
  • Queue / streaming systems
  • Distributed workers & async processing
  • APIs & microservices

Also used

  • Docker, Kubernetes & cloud infrastructure
  • Rust
  • Caching layers
  • Retrieval & search systems
  • ML feature pipelines
  • Large dataset processing

AI-native engineering

We actively use AI coding tools as part of daily development.

You should be comfortable working with tools such as:

  • Claude Code
  • Codex
  • Similar LLM-assisted development environments

The ideal candidate

What we are looking for

You have built real systems – not just scripts.

You have experience with:

  • Production Python systems
  • Scalable data pipelines
  • High-volume event processing
  • MongoDB or document databases
  • Queue based architectures (Kafka, RabbitMQ, SQS or similar)
  • Debugging performance and failure modes
  • Designing systems other engineers can safely build on

Nice to have

  • Recommendation or personalization systems
  • ML data preparation pipelines
  • Ecommerce domain experience

What you get

  • A senior engineering team with high autonomy
  • Close collaboration between product, ML and engineering
  • Onsite collaboration with flexible workdays
  • Competitive salary
  • A culture that values building technology that users actually use

Apply for this position

We'd love to hear from you. Send your CV and a short cover note.

What we offer

Perks

Catered lunches

Ordered from local Copenhagen spots every day.

Get better. Every day.

We mentor all employees and integrate learning into your position.

Gear matters

PC, Macbook, trackpad, you name it, we get you covered.

Location. Location. Location.

Super easy public transit access.

Got social?

Rooftop deck for social gatherings, events, and Friday bars.

Daily treats

Breakfast on Mondays and fresh fruit, snacks, and candy every day.

At the frontier of AI

Want to be a part of the AI revolution? Welcome.

A healthy workplace

Leadership is committed to fostering a fun, energetic, accommodating, and mentally healthy workplace.

About Hello Retail

Hello Retail started its journey in 2013, to become today's ecommerce personalization platform that helps merchants across the globe stay relevant in a competitive market, maximize profits, and create unique experiences tailored to each visitor.

At the beginning of 2023, we announced our innovative predictive software – Product Intelligence – which has become the AI backbone of our personalization platform. The world and the ecommerce climate are ever-changing, and we aim to empower our customers who want to be at the forefront of innovation.

Today, we are almost 70+ people based in Copenhagen with different nationalities which gives a great, international atmosphere. We are relaxed but ambitious, we have fun but know when to work. We cooperate but are fully aware of the value of being self-driven and motivated.

If you do not know Copenhagen already, the capital of Denmark oozes of atmosphere, lots of shopping, restaurants and cafés, and cool hangout places. You can cross Copenhagen by bike or electrical scooter in no time to go for street food, maybe even kayaking in the canals, or ice skating in the wintertime.

Our brand new office is only a 5-minute walk from the Metro Station. If you live in Southern Sweden you can tag along our other employees living in Sweden going by train from Malmö to Copenhagen daily. We have made it as easy as it gets.