(Senior) Applied Scientist, Recommendations

Wolt; Stockholms kommun; On-site; SEK 600,000 - 900,000; Full time

Job summary

Wolt in Stockholm is seeking an Applied Scientist to advance our ML models behind recommendations, ranking and content retrieval. You’ll take ideas from problem framing to production deployment, measure customer impact and guide product decisions.

You’ll collaborate with software engineers, ML engineers, product managers and analysts to translate scientific insights into reliable, customer-facing features. You will evaluate novel methods, balance relevance with business constraints and help

Qualifications

• Hands-on experience applying ML to real-world problems and bringing models to production.
• Experience with recommender systems, ranking, retrieval or closely related ML problems.
• Ability to turn ambiguous problems into well-scoped ML approaches and drive measurable outcomes.

Responsibilities

• Design, develop and improve ML models for recommendations, ranking and content retrieval.
• Own end-to-end ML problems: frame, analyze data, build models, evaluate offline, run experiments, monitor production.

Skills

Machine Learning

Python

Recommender Systems

Production ML

Education

PhD in ML/related field

Tools

TensorFlow

PyTorch

Job description

About Wolt
At Wolt, we create technology that brings joy, simplicity and earnings to the neighborhoods of the world. In 2014 we started with delivery of restaurant food. Now we’re building the delivery of (almost) everything and you’ll find us in over 500 cities in 30 countries around the world. In 2022 we joined forces with DoorDash and together we keep on dreaming big and expanding across the globe.

About Wolt
At Wolt, we create technology that brings joy, simplicity and earnings to the neighborhoods of the world. In 2014 we started with delivery of restaurant food. Now we’re building the delivery of (almost) everything and you’ll find us in over 500 cities in 30 countries around the world. In 2022 we joined forces with DoorDash and together we keep on dreaming big and expanding across the globe.
Working at Wolt isn’t always easy, but it’s definitely exciting. Here you’ll learn more, build more, and ship more than in most other companies. You’ll be challenged a lot, but also have a lot of fun on the way. So, if you’re a self-starter with drive and entrepreneurial spirit, this could be the ride of your life.
Wolt is part of DoorDash - together we form one of the world’s largest local commerce platforms. We build recommendation systems that help customers discover the most relevant restaurants, dishes and items throughout their Wolt experience.
We are looking for an Applied Scientist to advance the machine learning models behind these experiences. You’ll work on challenging applied ML problems where model quality, product decisions and customer experience are tightly connected. This is an opportunity to take ideas from problem framing and data analysis through experimentation, production deployment and measurable customer impact.
What you’ll be doing

• Design, develop and improve recommendation, ranking and retrieval models that surface relevant restaurants, dishes, items and content to customers.
• Own applied ML problems end to end: frame the problem, analyze data, develop models, define offline evaluation, run experiments and monitor production performance.
• Develop methods that balance relevance with product and customer needs, such as diversity, availability, business constraints and changing user intent.
• Collaborate closely with Software Engineers, ML Engineers, Product Managers and Analysts to turn scientific insights into reliable customer-facing products.
• Evaluate and apply state-of-the‑art ML methods where they meaningfully improve recommendation quality, robustness or efficiency.
• Contribute to a high bar for applied‑science practice through technical reviews, knowledge sharing and thoughtful experimentation.

Our humble expectations

• You have substantial hands‑on experience applying machine learning to real‑world problems and a track record of bringing models from development into production; a PhD with relevant applied research experience is equally welcome.
• You have experience with recommendation systems, ranking, retrieval, personalisation, or closely related ML problems.
• You can independently turn an ambiguous customer or product problem into a well‑scoped ML approach, make sound trade‑offs and drive it to a measurable outcome.
• You are proficient in Python and experienced with modern ML frameworks and large‑scale data processing.
• You understand how to evaluate ML systems rigorously, including offline metrics, experiment design and interpreting online results.
• You communicate complex technical ideas clearly and work effectively with cross‑functional partners.

What we offer

You will work on recommendation problems with direct, measurable impact on how customers discover relevant content. You’ll collaborate with experienced scientists and engineers across DoorDash, Deliveroo and Wolt, learning from multiple recommendation systems while helping shape the next generation of the experience.
Together with your lead, you will have the opportunity to create a personalised development plan that builds on your strengths and develops new capabilities.

Our Commitment to Diversity and Inclusion

We’re committed to growing and empowering a more inclusive community within our company, industry, and cities. That’s why we hire and cultivate diverse teams of people from all backgrounds, experiences, and perspectives. We believe that true innovation happens when everyone has room at the table and the tools, resources, and opportunity to excel.