Search - Workchat - Senior Data Scientist

Overview Senior Data Scientist role in Elastic's Search - Workchat team. You will help build a conversational (agentic) platform that lets customers chat with their own data in Elasticsearch. You will participate in cross-functional work with backend, DS, PM, and UX to drive chat quality end-to-end, including designing evaluation pipelines, improving prompts and tool behaviors, and turning measurements into product decisions that customers can feel.

What You Will Be Doing Design and maintain offline / online evaluation pipelines for conversational search : golden sets, rubric / LLM-as-judge calibration, groundedness / citation checks, and A / B tests.

Build and compare retrieval & re-ranking baselines (sparse + dense), query understanding, and semantic rewrites; land improvements with clear metrics.

Use results to drive product decisions : model selection, efficient agent routing, tool gating, and agent customization for Elastic use cases in search and beyond.

Instrument dashboards and telemetry so helpfulness, faithfulness, latency, and cost trade-offs are visible and trustworthy; guard against regressions in CI.

Collaborate with backend engineers on contracts (ES|QL, citations, telemetry), and with PM / UX to translate findings into shipped features.

Share outcomes clearly (docs, notebooks, PRs) and mentor peers in experiment design and evaluation craft.

What You Will Bring 5–8 years in applied DS / ML with strong IR / NLP experience (RAG, dense / sparse retrieval, re-ranking, vector search).

Proficiency in Python, PyTorch / Transformers, Pandas; reproducible experiments (e.g., MLflow), versioned datasets, and clean, reviewable code.

Hands-on evaluation expertise : offline metrics (nDCG / MRR / Recall@k), LLM-as-judge calibration, groundedness / citation scoring, and online A / B testing.

Experience turning experimental results into clear product calls (models, routing, tools) and communicating them crisply to cross-functional partners.

Practical Elasticsearch experience (or similar); ES|QL familiarity is a plus.

Comfort working in a distributed, async-first environment; strong written communication; low-ego collaboration.

Compensation and Benefits Compensation for this role is in the form of base salary with a typical starting range listed below. The role does not include a variable compensation component. Elastic offers a stock program and a 401k with employer matching up to 6% of eligible earnings, plus a range of benefits focused on well-being.

The typical starting salary ranges are :

Not location-specific : $133,100—$210,600 USD

In select locations (including Seattle WA, Los Angeles CA, the San Francisco Bay Area CA, and the New York City Metro Area) : $159,900—$252,900 USD

Additional Information Elastic is committed to diversity and inclusion. We provide accommodations during the application process upon request at candidate_accessibility@elastic.co. We post rights under Federal Employment Laws and provide links to posters such as FMLA, EEO, and EPPA. We encourage applicants from diverse backgrounds and offer equal opportunity in employment.

Location Madrid, Community of Madrid, Spain

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