Remote Senior ML Engineer - Retrieval & Multimodal Search

Lever, Inc.; Netherlands; Remote; EUR 71,000 - 106,000; Full time

Benefits offered by this job

Fully remote working environment

Apple laptop provided

Job summary

Lever, Inc. seeks a Senior Machine Learning Engineer for ML Recall, based in the Netherlands, to shape the retrieval layer of a large-scale e-commerce search engine.

You will own end-to-end ML initiatives, from problem framing to deployment, optimizing dense and sparse retrieval, partial multilingual signals, and multimodal search. You will work with transformer-based models, balance relevance with millisecond latency, and run production experiments and A/B tests in a remote-first environment.

Qualifications

• 4+ years of experience building and shipping production machine learning systems.
• Professional experience with search, information retrieval, recommendation systems, or closely related machine learning applications.
• Hands-on experience training, fine-tuning, and evaluating transformer-based models.
• Strong Python and PyTorch skills, with practical experience developing production-quality ML solutions.
• Familiarity with data orchestration and large-scale data processing tools such as Spark and Airflow.
• Demonstrated experience owning machine learning models end to end, from problem formulation and experimentation to deployment and production monitoring.
• Experience designing and running A/B tests and using experimental results to assess and improve model impact.
• Strong analytical and problem-solving abilities, particularly when working with complex retrieval and relevance challenges.
• Excellent English communication skills and the ability to collaborate effectively in a distributed, technical environment.

Responsibilities

• Develop and optimize modern search retrieval systems using dense and sparse models, query understanding, and other machine learning techniques.
• Build solutions that balance retrieval quality and strict latency requirements, ensuring relevant products are returned within milliseconds.
• Develop end-to-end visual and multimodal search capabilities, including image search, visual recommendations, and "shop the look" experiences.
• Train, fine-tune, evaluate, deploy, and continuously improve deep learning models used across multiple products and teams.
• Experiment with new model architectures, retrieval approaches, and techniques, validating their effectiveness through A/B testing and live traffic experiments.
• Address complex measurement challenges in search recall by developing reliable ground truth and evaluation methodologies for products that may otherwise be missed entirely.
• Design models that generalize across 40+ languages and 20+ domains without relying on customer‑specific rules or overrides.
• Take ownership of machine learning initiatives from problem framing and research through production rollout and ongoing optimization.
• Collaborate with other engineering and machine learning teams whose products build on the models and capabilities you develop.

Skills

Python

PyTorch

Spark

Airflow

English communication

A/B testing

Distributed systems

Problem solving

Tools

Transformers

Job description

Lever, Inc. seeks a Senior Machine Learning Engineer for ML Recall, based in the Netherlands, to shape the retrieval layer of a large-scale e-commerce search engine.

You will own end-to-end ML initiatives, from problem framing to deployment, optimizing dense and sparse retrieval, partial multilingual signals, and multimodal search. You will work with transformer-based models, balance relevance with millisecond latency, and run production experiments and A/B tests in a remote-first environment.