Backend Engineer - Search (all genders)
About You SE & Co. KG2 days ago
Hamburg, Germany or Berlin, GermanyMid Level
Responsibilities
- Develop the ABOUT YOU search engine with a focus on query understanding, entity resolution, and semantic vector search.
- Combine OpenSearch relevance, embedding similarity, and behavioral re-ranking signals to produce relevant search results.
- Build and maintain search-index pipelines for entities, synonyms, and k-NN product vectors using data from BigQuery.
- Integrate Gemini and Vertex AI embedding and LLM models under strict latency requirements, including caching and fallback mechanisms.
- Improve search quality through golden lists, regression suites, and continuous A/B experiments.
- Collaborate on architecture with the Tech Lead and work closely with data analysts, engineers, and product managers.
Requirements
- At least 3 years of experience developing scalable, low-latency backend APIs, ideally with Node.js and TypeScript.
- Alternatively, experience with Java, Go, or Kotlin and the ability to learn new technologies quickly.
- Deep practical experience with Elasticsearch or OpenSearch, including mappings, custom analyzers, percolators, and scoring functions.
- Strong algorithmic understanding of ranked data, including result merging and deduplication, score combination, and latency-versus-quality tradeoffs.
- Interest in combining backend engineering and machine learning and deploying model scores, embeddings, or LLM features in production systems.
- Very good English communication skills and a pragmatic, data-oriented, curious working style.
- Nice to have: information retrieval and NLP knowledge, including tokenization, multilingual search, or search-relevance evaluation frameworks.
- Nice to have: vector-search experience with k-NN/HNSW indexes and SigLIP embeddings, including recall and latency optimization.
- Nice to have: LLM engineering experience with prompt caching, timeout budgets, or Datadog LLM Observability.
- Nice to have: familiarity with BigQuery, dbt, Dagster, and related data pipelines.
Benefits
- The company promotes an inclusive workplace where people can be themselves and values acceptance, inclusion, and fair treatment.
- The role is associated with ABOUT YOU locations in Hamburg and Berlin.
- Employees can participate in team lunches, after-work drinks, company events, and informal coffee breaks.
- Applications are submitted online, with feedback promised as soon as possible.
About About You SE & Co. KG
ABOUT YOU SE & Co. KG operates an online fashion marketplace for European consumers and licenses commerce technology to brands via its SCAYLE platform. The group sells apparel and lifestyle products through its mobile app and aboutyou.com, and offers a cloud-based enterprise shop system under a license model to retailers. Founded in 2014 and headquartered in Hamburg, it is a publicly listed company.