Senior Machine Learning Engineer: Search Quality (Remote)
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 Senior Machine Learning Engineer in the Search Quality team, you will improve the e-commerce experience for hundreds of millions of users across the world by building the systems that power relevance for global retailers - from fashion and grocery to electronics and hardware.
The mission is to measure search quality, push it higher, and catch degradations before the user does. You will achieve this through a blend of fine-tuned LLMs for relevance judgment, real-time models, and deep offline analysis of query logs.
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.
- No universal ground truth. A grocery retailer and a fashion retailer may have different perceptions on what "relevant" means.
- Efficiency at scale. Optimizing and scaling LLM inference across our entire customer base.
What you'll do
- LLM-based evaluation. We fine-tune our own models to assess relevance. This involves teaching the model to understand query intent, represent items from messy catalog data, and align model judgments with real user behavior.
- Real-time quality in production. Reranking, filtering, signal computation. Latency is a strict requirement, so quality vs speed tradeoff is constant.
- Automated quality monitoring and agentic insights. Pipelines to detect degradations and find underperforming patterns. Agent-based systems that generate actionable recommendations for the product data and search configurations.
Requirements
- 4+ years shipping production ML systems
- Experience with search, information retrieval, or recommendation systems
- Hands-on experience with fine-tuning, evaluation frameworks, and scaling LLM deployments
- Strong Python and PyTorch. Fluency in SQL and data orchestration tools (Spark, Airflow)
- Experience designing and running A/B tests to validate model impact
- Excellent English communication skills
- Experience collaborating in cross-functional teams (ranking, product, data engineering)
Benefits
- 🧠 Work with smart and empathetic people who will help you grow and make a meaningful impact.
- 🎉 Regular team offsite events to connect and collaborate.
- 🌎 Fully remote team - choose where you live.
- 🏝️ Unlimited vacation time - we strongly encourage all of our employees take at least 3 weeks per year.
- 🛋️ 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.
- 💵 Base salary: $80k–$120K USD, depending on knowledge, skills, experience, and interview results
- 📈 Stock options - offered in addition to the base salary
Who you are
The description mentions collaboration in cross-functional teams including ranking, product, and data engineering, but specific "who you are" criteria are encompassed in the requirements above, including communication skills and experience across domains.
