# Senior Machine Learning Engineer, Personalization, Rewards
**Company:** [Spotify](https://hotfix.jobs/companies/spotify)
**Location:** Remote
**Experience:** 5+ years
**Skills:** Machine Learning, Reinforcement Learning, Statistics, Optimization, Sequential Models, Transformers, Generative AI, LLMs, Fine-Tuning, A/B Testing
**Posted:** 2026-05-12
> Machine Learning Engineer focused on Reinforcement Learning for personalization and reward modeling in Spotify's recommendation systems. Requires RL expertise and experience with LLMs, transformers, and A/B testing.
## Job Description
## What You'll Do
- Contribute to designing, scaling/building, evaluating, integrating, shipping, and refining reward signals for recommendations by hands-on ML development.
- Lead collaborations and align across PZN to integrate and A/B test mid-term signals in various recommendation and discovery systems.
- Promote and role-model best practices of ML systems development, testing, and evaluation throughout the organization.
- In your first 6 months, you will be responsible for ML development: prototyping models, building pipelines, productizing/scaling models, and launching A/B tests for personalized generative recommendations at Spotify.

## Who You Are
- You have a strong background in machine learning and enjoy applying theory to develop real-world applications.
- Reinforcement Learning (RL) expertise is key, and experience in RL for recommendations is a must have.
- Expertise in statistics and optimization, especially in sequential models, transformers, generative AI, large language models (LLMs are a plus), and relevant fine-tuning processes.
**Apply:** https://hotfix.jobs/jobs/senior-machine-learning-engineer-personalization-rewards-at-spotify-39f14e9f-5d6e-4831-a9e3-013f0cca55a9
**Canonical:** https://hotfix.jobs/jobs/senior-machine-learning-engineer-personalization-rewards-at-spotify-39f14e9f-5d6e-4831-a9e3-013f0cca55a9