Principal ML Engineer: Matching & Personalisation

Bumble Inc.; Greater London; On-site; GBP 120,000 - 170,000; Full time

Job summary

Bumble Inc. is seeking a Principal Machine Learning Engineer, Matching & Recommendations in London to define the ML strategy and remain hands-on across retrieval, ranking, personalization and experimentation.

You will lead cross-functional work with Engineering, Product and Data Science to deliver scalable ML solutions that improve member outcomes. We value Python proficiency, PyTorch/TF expertise and experience with large-scale ML systems, LLMs, and responsible AI practices.

Qualifications

• 10–15 years of relevant experience in ML engineering or equivalent.
• Deep expertise in building large-scale ML systems in production.
• Strong Python skills and experience with PyTorch or TensorFlow.
• Experience with recommender/ranking systems and NLP is a plus.

Responsibilities

• Define and lead the ML strategy for AI/machine-learning systems powering recommendations and matching.
• Design, develop and deploy production-grade models in high‑traffic environments.
• Build AI agents and integrate LLM-based capabilities and MCP integrations.
• Architect end‑to‑end ML pipelines with Spark and Airflow; manage experimentation.
• Mentor senior engineers and influence across teams toward responsible AI.

Skills

Python

PyTorch

ML systems design

Large Language Models

A/B testing

Mentoring

Cross-functional leadership

Spark

Airflow

Tools

Spark

Airflow

LLM tooling

Job description

Bumble Inc. is seeking a Principal Machine Learning Engineer, Matching & Recommendations in London to define the ML strategy and remain hands-on across retrieval, ranking, personalization and experimentation.

You will lead cross-functional work with Engineering, Product and Data Science to deliver scalable ML solutions that improve member outcomes. We value Python proficiency, PyTorch/TF expertise and experience with large-scale ML systems, LLMs, and responsible AI practices.