
Spotify
Senior Machine Learning Engineer - Messaging Platform
HybridSeniorLondon, England, the United KingdomAI/MLPlatform
Our Take
Build ML models optimizing Spotify's messaging to over a billion users.
What you’ll do
- Design, build, and ship ML models for messaging optimization
- Plan and run A/B experiments
- Contribute to reinforcement learning systems
- Partner with product managers and engineers
- Own the full ML lifecycle
- Integrate ML models with upstream systems
- Shape AI-assisted development within the team
What they’re looking for
- Build and deploy ML models in production at scale
- Translate business problems into ML solutions
- Experience with complex optimization problems
- Hands-on experience with PyTorch
- Experience with distributed systems (Ray)
- Deep understanding of experimentation and A/B testing
- Experience with reinforcement learning
What you get
- Flexibility to work where you work best
- Work from home flexibility
- Equal opportunity employer
- Inclusive recruitment process
Skills & Focus Areas
- machine learning
- PyTorch
- A/B testing
- reinforcement learning
- optimization
- deployment
- monitoring
- causal inference
As posted by Spotify
Spotify’s Subscriptions Mission focuses on converting listeners into lifelong subscribers by delivering seamless, valuable experiences across pricing, packaging, and customer journeys. We build the systems and tools that power acquisition, retention, and overall subscription growth at scale.
Design, build, and ship machine learning models that optimize messaging across push, email, and in-app channels
Plan and run A/B experiments in a multi-objective environment, balancing conversion, engagement, retention, and reachability
Contribute to reinforcement learning systems that optimize for long-term user outcomes rather than immediate interactions
Partner with product managers, data scientists, and engineers to define what success looks like and how to measure it
Own the full ML lifecycle, from data and modeling to deployment, monitoring, and iteration
Integrate ML models with upstream systems, including domain value signals and opportunity generation frameworks
Help shape the future of AI-assisted development within the team, exploring how tools can accelerate experimentation and delivery
The Messaging Platform powers Spotify’s communications to over a billion users — from push notifications to emails and in-app messages that connect listeners to the content they love. Within this space, the Paloma squad focuses on message optimization: deciding which message reaches which user, through which channel, and at what moment.
We’re evolving how messaging works at Spotify — moving from short-term optimization toward systems that understand long-term user journeys. By combining reinforcement learning approaches with deeper domain signals, we’re expanding how machine learning shapes the entire messaging funnel.
What You'll Do
Who You Are
- You have strong experience building and deploying machine learning models in production environments at scale
- You are comfortable translating business problems into ML solutions and discussing trade-offs with cross-functional partners
- You have worked on complex optimization problems such as ranking systems or multi-objective decision-making
- You bring hands-on experience with PyTorch and distributed systems such as Ray or similar frameworks
- You understand experimentation deeply and can design reliable tests in environments with interacting metrics
- You are able to analyze results using approaches like causal inference or metric decomposition when needed
- You have experience with or curiosity about reinforcement learning and long-term optimization systems
- You enjoy working across disciplines and navigating ambiguity while shaping strategy and direction
Where You'll Be
- This role is based in London and Stockholm
- We offer you the flexibility to work where you work best! There will be some in person meetings, but still allows for flexibility to work from home