Senior Backend Engineer - Search & Discovery, All genders

Job Description

• Develop the search engine behind ABOUT YOU, covering query understanding, entity resolution, and semantic vector search in Node.js/TypeScript
• Blend OpenSearch relevance, embedding similarity, and behavioral re-ranking signals into unified search results
• Build search-index pipelines (entities, synonyms, k-NN product vectors) streaming data from BigQuery into OpenSearch
• Integrate LLMs and embedding models (Gemini, Vertex AI) under tight latency budgets with caching and fallback layers
• Guard search relevance using golden lists, regression suites, and continuous A/B experiments
• Shape architecture alongside our Tech Lead and collaborate closely with data analysts, engineers, and product managers

Qualifications

• You love investigating the "why" behind search outcomes and turning those findings into actionable technical improvements
• 5+ years of experience building scalable, low-latency backend APIs (Node.js/TypeScript preferred, or fast-converting from Java, Go, or Kotlin)
• Real depth in Elasticsearch/OpenSearch (mappings, custom analyzers, percolators, scoring functions) beyond just basic query clients
• Strong algorithmic intuition for ranked data (merging, deduplication, score blending, and latency trade-offs)
• You're excited to bridge backend engineering and ML by serving model scores, embeddings, or LLM features in production
• Fluent English communication skills and a pragmatic, data-curious mindset

Nice to Have

• IR/NLP fundamentals (tokenization, multilingual search, relevance evaluation frameworks)
• Vector search experience (k-NN/HNSW indices, SigLIP embeddings, recall vs. latency tuning)
• LLM engineering (prompt caching, timeout budgets, Datadog LLM Observability)
• Familiarity with BigQuery, dbt, or Dagster pipelines

Additional Information

Your perks at a glance: Visit our benefits page.

Simply apply online via our career page - we will get back to you as soon as possible!

A Place Where You Can Be You
We take it as our responsibility to create an environment where everyone feels welcome, exactly as they are.
Different backgrounds and perspectives make us stronger and shape our culture in ways that matter.
What we stand for internally, we stand for as a brand: acceptance, inclusion, and a fairer approach to fashion.

Compensation: 70000 to 85000 (EUR) (YEARLY)