Senior Software Engineer - Search F/H

Join Qobuz, a leading music streaming service, as a Senior Software Engineer specializing in search. You will lead the migration of our search infrastructure to a modern, scalable platform, own search relevance end-to-end, and operate a 24/7 production service. You will collaborate closely with product, data, and catalog teams in a small, autonomous environment.

• Lead the design and migration of the search architecture to a modern, scalable platform.
• Own search relevance end-to-end, including ranking, indexing, query understanding, and evaluation.
• Build and maintain the analytics, A/B testing, and KPI frameworks that drive continuous improvement in search quality.

**What we're looking for:**

• Proven experience building and operating a large production search system
• Strong expertise in **full-text and semantic search** on large-scale catalogs (100M+ records) across multiple languages
• Hands-on experience with modern search stacks such as **Elasticsearch, OpenSearch, or Vespa**
• Experience building **ranking, indexing, analytics, and A/B testing** pipelines for search
• Experience defining and tracking **success and failure KPIs** for search quality
• Track record running a **24/7 service with strong operational constraints** — tens of millions of queries per day, tight response-time SLAs
• Solid grounding in **information retrieval fundamentals**: BM25, text matching, scoring mechanics, relevance tuning
• Experience with **AWS cloud architecture**
• Comfort with **data pipelines and ETL** (batch and streaming), working with cloud data warehouses and object storage
• Experience leading at least one **major system migration** — dual-write patterns, shadow testing, gradual rollouts, and rollback strategies

**Our stack :**

• **API:** PHP (Symfony) — PHP/Symfony experience is a plus
• **Data:** SQL databases, Snowflake data warehouse
• **Cloud:** AWS
• **Tooling:** JIRA, Confluence

**Bonus points :**

• Experience with **metadata quality issues in the music industry**
• Experience with **personalization algorithms**
• Using **ML tools to improve metadata quality**
• Familiarity with ML-based ranking techniques (learning to rank, embedding-based retrieval)
• Knowledge of relevance evaluation metrics (NDCG, MRR, MAP)
• Experience with multilingual and CJK search challenges (tokenization, multi-script handling)
• Experience working in a small, autonomous team owning the full stack from data pipeline to query serving