Senior Machine Learning Engineer: ML Recall

About Us

Launched in 2019, Constructor is an AI-first ecommerce search and discovery platform that helps shoppers find the right products at the right time and enables leading global e-commerce brands to drive meaningful revenue and conversion gains.

As a member of the ML Recall team, you will improve the e-commerce experience for hundreds of millions of users across the world by building the retrieval layer of our search engine.

The mission is to make sure the product a shopper looks for is always among the results - for any query, in any language, in a few milliseconds.

About the Job

Your primary focus will be search retrieval and visual solutions:

• Search Recall. A modern retrieval stack with dense and sparse models, plus query understanding. Latency is a strict requirement, so quality vs speed tradeoff is constant.
• Visual and multimodal search. End-to-end visual solutions: image search, shop the look, visual recommendations.
• Models as a platform. Our team owns a wide range of deep learning models, and other teams build on top of them.

What makes this interesting

• Multi-domain, multi-language, at scale - 40+ languages, 20+ domains. The models need to generalize across all of them - without per-customer rules or overrides.
• Real room for R&D. You will experiment with new architectures and approaches, A/B test them on live traffic, and deliver measurable business value.
• The measurement challenge. You can't measure what was not returned - a missed product leaves no trace in the logs, and the query looks like it worked. Building the ground truth to catch that is part of the modeling work.

Requirements

• 4+ years shipping production ML systems
• Experience with search, information retrieval, or recommendation systems
• Hands-on experience training, fine-tuning, and evaluating transformer models
• Strong Python and PyTorch. Fluency in data orchestration tools (Spark, Airflow)
• Experience owning a model end to end - from problem framing to rollout
• Experience designing and running A/B tests to validate model impact
• Excellent English communication skills

Benefits

• 🏝️ Unlimited vacation time - we strongly encourage all of our employees take at least 3 weeks per year
• 🌎 Fully remote team - choose where you live
• 🛋️ Work from home stipend! We want you to have the resources you need to set up your home office
• 💻 Apple laptops provided for new employees
• 🧑‍🎓 Training and development budget for every employee, refreshed each year
• 👪 Maternity & Paternity leave for qualified employees
• 🧠 Work with smart people who will help you grow and make a meaningful impact
• 💵 Base salary: $80k–$120k USD, depending on knowledge, skills, experience, and interview results
• 📈 Stock options - offered in addition to the base salary
• 🎉 Regular team offsites to connect and collaborate

Diversity, Equity, and Inclusion at Constructor

At Constructor.io we are committed to cultivating a work environment that is diverse, equitable, and inclusive. As an equal opportunity employer, we welcome individuals of all backgrounds and provide equal opportunities to all applicants regardless of their education, diversity of opinion, race, color, religion, gender, gender expression, sexual orientation, national origin, genetics, disability, age, veteran status or affiliation in any other protected group.

Studies have shown that women and people of color may be less likely to apply for jobs unless they meet every one of the qualifications listed. Our primary interest is in finding the best candidate for the job. We encourage you to apply even if you don’t meet all of our listed qualifications.