Principal Data Scientist

Jotelulu
Jotelulu
Hibrido, SpainOn-siteCompetitiveAdded 4 months agoMidPermanent
Jotelulu

Principal Data Scientist

Original Advert

Your mission?

Turn our rich operational and product telemetry into trustworthy, timely, secure, and business-ready data. Build the semantic layer and pipelines that power GTM, Product, Operations, and Partner Success-so decisions are faster, experiments are rigorous, and growth is compounding.


The role


What are we looking for?
We're hiring a Principal Data Scientist / Developer-part architect, part builder, part strategist-to own our end-to-end data foundation and accelerate impact from insights to shipped improvements.

You'll partner with Product and Engineering leads to design the next-gen data platform (batch and streaming), define metrics and contracts, and ship models (analytics, ML, and LLM-assisted) that lift activation, expansion, and reliability.

Reporting to the COO, you'll work hands-on while coaching others, translating business questions into robust, production-grade data products. This role is based in Madrid, Spain, with a hybrid work model.

This isn't about dashboards alone-it's about building the engines that move the business.


What you'll own and drive

  • End-to-end data infrastructure: From ingestion to orchestration to serving (batch/stream), optimizing cost, reliability, and speed.

  • Data quality, integrity, and availability: CI/CD for data, contracts, tests, and observability as first-class citizens.

  • Pipelines & processes: Design/optimize ingestion, transformation, and analysis workflows for structured and unstructured data.

  • Insights to action: Partner with GTM, Product, Operations, and Partner Success to prioritize questions, run experiments, and land changes.

  • Models & semantics: Own core metrics, semantic layers, reporting models, and feature stores aligned to the partner funnel (SQL→MQL→SQL→ARR).

  • Governance & collaboration: Lineage, catalog, permissions, and clear documentation so teams can self-serve safely and confidently.

Day-to-day tasks

  • Design/optimize pipelines (ingestion, transformation, orchestration).

  • Develop and maintain analytical and ML/LLM models (structured/unstructured; stats/experimentation).

  • Implement/improve dashboards (Dash/Plotly, Power BI, Tableau, Looker).

  • Analyze trends/patterns to improve processes, product, and the partner funnel.

  • Data modeling (dimensional, lakehouse, feature stores).

  • Data quality & observability (detect/fix inconsistencies).

  • Coordinate accessibility & usability (catalog, lineage, permissions).

  • Automate extraction/transformations, data testing, and deployment.

  • Document best practices, standards, and methodologies.


Tooling you'll use
Linux, bash, Git, Containerization; SQL/NoSQL; Flask/FastAPI for APIs; Data stack: Pandas, scikit-learn, Polars, DuckDB; DL stack: PyTorch, HuggingFace, TensorFlow; Dash/Plotly/Power BI; Slack; Microsoft O365; Jira; Confluence; Cloud platforms & data services.


What will make us fall in love with you as a candidate?

It will be a perfect match if...

  • You are proactive. You spot data gaps early and propose scalable solutions without waiting for direction.

  • You prioritize clarity over clutter. You define crisp metrics and contracts, and make complex systems understandable.

  • You rock in strategic storytelling. You turn analysis into compelling narratives that move execs and engineers to act.

  • You are brave & creative. You experiment fast, embrace feedback, and solve problems others deem "too technical" or "too messy."

  • You simplify the complex. You design data models and APIs that make cloud workflows intuitive for partners and internal teams.

  • Ownership. You can lead the full data lifecycle-from ingestion to models to serving and observability-hands-on and end-to-end.

  • You love being the bridge between tech and business. You translate questions into analysis, and insights into shipped changes.

  • For you, user and business impact go first. You champion data integrity and responsible AI to improve real outcomes.

  • Trust. You give and receive feedback thoughtfully, with the intent to build, and you lead with transparency.


Requirements that are important for us

Please, only apply if you match these.

  • A principal level: 8+ years across Data Science/Analytics/Engineering (including leading initiatives), with shipped data products and measurable business impact.

  • Mastery of data tooling: Python (preferred) and/or R; SQL & NoSQL; visualization (Power BI, Tableau, Looker, Dash/Plotly); ML/LLM/stats; cloud data services. You use AI responsibly to speed up quality work.

  • English skills: Intermediate level required - Level B1 minimum (B2+ is a plus) to collaborate with international teams.


Data

  • SQL & NoSQL excellence: Schema design, performance tuning, partitioning, indexing.

  • ETL/ELT & orchestration: Reliable pipelines (batch/stream) with monitoring, alerting, and recovery.

  • Modeling: Dimensional modeling, lakehouse patterns, and feature stores that serve analytics and ML.

  • ML/LLM & experimentation: From baseline models to rigorous A/B tests and causal inference on structured/unstructured data.

  • Visualization: Power BI, Tableau, Looker, and Dash/Plotly for decision-ready views.

  • Observability & governance: Data tests, lineage, contracts, catalogs, and CI/CD for data.

  • Quality by design: Freshness, completeness, accuracy, and SLAs as non-negotiables.


Engineering

  • System design & architecture: Comfortable with monoliths, microservices, and event-driven patterns.

  • APIs & services: Build/consume services with Flask/FastAPI; productionize models and data apps.

  • Cloud & data services: Practical fluency with cloud storage/compute and managed data offerings.

  • Core stack: Python, Pandas, Polars, DuckDB, scikit-learn; DL with PyTorch/TensorFlow/HuggingFace.

  • DevX: Linux, bash, Git, containerization; automation, testing, and CI/CD for code and data.

  • Security-minded: Design with least privilege, encryption, and secure defaults.


Security & Compliance
The Data Analytics team ensures secure and responsible data use in line with ISO 27001, ENS, and HDS-protecting confidentiality, integrity, and availability.


We anonymize and encrypt where applicable, enforce access controls, uphold data quality, and ensure that analysis tools/platforms are compliant. You'll work closely with our Security team to bake this into architecture and day-to-day operations.

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