Carlos León
enes

Experience

Where I've worked.

Data engineering, BI, and machine learning across consulting, the public sector, and energy.

Resume (PDF)

  1. Sep 2025 - Present

    Data Engineer · Astrafy

    Building data platforms and data products on Google Cloud for finance and marketing teams, from ingestion and dbt modeling to CI/CD, infrastructure as code, and self-serve analytics.

    • Built and owned analytics data products on GCP, BigQuery, dbt, and Airflow across 5+ initiatives supporting finance and marketing KPIs
    • Designed and maintained production dbt projects with 100+ models across staging and marts, reducing analytics inconsistencies by around 30%
    • Implemented CI/CD and Infrastructure as Code with GitLab CI, Terraform, and GCP IAM, reducing setup and deployment issues by around 40%
    • Delivered self-serve dashboards in Lightdash and Looker used by 10+ stakeholders for reporting and decision-making
    • Python
    • SQL
    • dbt
    • GCP
    • BigQuery
    • Airflow
    • Terraform
    • Looker
    • Lightdash

  2. Oct 2024 - Sep 2025

    BI Engineer · SII Group Spain

    Developed data engineering and BI solutions for the Ministry of Defense, improving planning, reporting, and visibility across financial and operational data.

    • Developed and automated data engineering and BI solutions used across 10+ departments
    • Built Power BI dashboards to monitor multi-million euro budgets for 4+ senior stakeholders
    • Automated ETL workflows with Python, SQL, and Bash, reducing processing time by 95%
    • Centralized and modeled historical datasets to improve reporting consistency and planning visibility
    • Python
    • SQL
    • Power BI
    • Bash
    • Docker
    • Elasticsearch

  3. Jul 2023 - Jan 2024

    Data Consultant · Minsait

    Worked on SQL-heavy data solutions, partnering with analysts and technical teams to improve performance, reliability, and process quality.

    • Optimized complex SQL queries, improving database performance by 20% and reducing retrieval times by 25%
    • Collaborated with functional analysts to translate business requirements into technical data solutions
    • Improved documentation standards and data processes, increasing team efficiency by around 30%
    • Strengthened delivery quality across a 10+ member technical team through clearer data processes
    • SQL
    • PostgreSQL
    • ETL

  4. Apr 2023 - Jul 2023

    Data Science Intern R&D · Red Eléctrica

    Worked at the intersection of analytics, machine learning, and innovation, building internal tools and dashboards for energy-market and R&D use cases.

    • Built analysis workflows and machine learning models to monitor 200+ energy market agents, cutting supervisor workload by 50%
    • Integrated Whisper for call transcription and documentation, improving reporting accuracy by 35%
    • Delivered 3 Power BI dashboards used weekly by 10+ analysts in the Markets Department
    • Managed 50+ R&D initiatives in the Innovation Lab and represented Elewit at industry events
    • Python
    • SQL
    • Power BI
    • AWS
    • Git
    • Machine Learning

Education & credentials

Education

  • Applied Data Science Program

    Zrive

    Intensive program covering end-to-end data science workflows, feature engineering, model development, and deployment with FastAPI.

  • BSc in Mathematics

    University of Extremadura

    Bachelor's thesis in game theory. Built a strong foundation in structure, modeling, and analytical thinking.

Certifications

  • Professional Data Engineer

    Google Cloud

    Professional certification focused on designing, building, operationalizing, securing, and monitoring data processing systems on Google Cloud.

  • Professional Cloud Architect

    Google Cloud

    Professional certification focused on designing secure, scalable, and reliable cloud architectures on Google Cloud.

  • Data Engineering: SQL, dbt, Snowflake & Power BI

    Cívica

    Focused on analytics engineering, data modeling, and modern warehouse workflows.