Javier – SQL, AWS, Python
With over 10 years of experience in the industry, Javier is a seasoned Data Engineer with a strong understanding of modern cloud environments and ETL workflows. Throughout his career, he’s managed teams of 4-6 engineers and held a CTO role at a startup. Beyond his core work, Javier contributes to open-source projects and teaches, reflecting his commitment to continuous learning and knowledge sharing.
12 years of commercial experience in
Main technologies
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Let’s get started today!Experience Highlights
Software Engineer
It's a task tracker used for personal needs.
- Developed back-end functionality using a microservice architecture.
- Built front-end components with FastHTML.
- Implemented notifications using the ntfy.sh service.
- Wrote unit and integration tests to ensure system reliability.
- Integrated LLMs to generate day-at-a-glance summaries.
Software Engineer
It's a wrapper around ntfy.sh service to foster and ease the implementation of shell notifications for any process. This package is designed explicitly for self-hosting services.
- Developed the core code wrapper.
- Designed system interactions and workflows.
- Open-sourced the project code.
Lead Software Engineer
It's an intrapreneur venture aimed at digitalizing a car dealership.
- Developed back-end architecture using a microservices approach.
- Built front-end interfaces to support back-office operations.
- Integrated with instant messaging providers.
- Integrated with credit score services, including Equifax.
- Deployed backend services through CI/CD pipelines, maintaining 99.999% uptime.
- Wrote unit, integration, and end-to-end tests to ensure system reliability.
Software Engineer
It's an open-source Python version of the Spicy IDs system.
- Developed an implementation of the Spicy ID framework in Python.
- Open-sourced the project code.
- Wrote comprehensive tests to ensure functionality and stability.
- Deployed the package to PyPI.
Senior Data Engineer
The project aimed to improve the quality and speed of data in the company’s data lake and data warehouses for a fintech platform serving businesses.
- Deployed the Dagster orchestrator for data workflow management.
- Developed DAGs to automate and manage data processing tasks.
- Integrated Dagster with DBT for data transformation and modeling.
- Implemented process triggers to streamline pipeline execution.
- Integrated the system with all relevant data sources and sinks.
Senior Data Engineer
It's a data lake development for a fintech platform serving businesses.
- Built a medallion-tiered data lake on Google Cloud Storage (GCS).
- Deployed a CDC solution using Datastream on GCP, integrating MySQL and PostgreSQL sources across multiple clouds.
- Implemented data lake pipelines with DBT across all layers.
- Built enriched One Big Tables to serve internal customer needs.
Lead Data Engineer
It's a credit scoring pipeline for a fintech platform serving businesses.
- Developed a scoring algorithm and refactored code using clean architecture.
- Built a pub/sub process for near-real-time and batch entity processing.
- Wrote unit and integration tests with Pytest.
- Deployed the solution on AWS.
Senior Data Engineer
It's a data lake development and maintenance for a utilities company from Chile.
- Created and deployed SSIS pipelines and artifacts to source data from SQL Server.
- Built and deployed PySpark pipelines to integrate data from additional sources.
- Developed a data lake and integrated it into a SQL Server database.
- Designed and populated multiple data warehouses.
- Maintained and optimized the data lake architecture.
Senior Data Engineer
It's a data lake for a utilities company to enhance its operations and facilitate cross-selling across multiple channels.
- Developed a data lake integrating data from multiple databases and platforms.
- Established a governed data management process based on the DAMA framework.
- Deployed batch and near–real-time data acquisition pipelines.
- Utilized BigQuery scheduled queries to create and maintain tables and views in a structured manner.
- Deployed PySpark pipelines to perform large-scale data transformations.
Senior Data Engineer
It's an ML containerization and deployment for a government agency to analyze its workload and enable operational efficiencies.
- Containerized an API-based ML model using Docker.
- Orchestrated Docker containers with Docker Compose.
- Deployed the solution on a remote platform using Make and Bash scripts.
- Developed and fine-tuned ML models using MLflow and Python.
Senior Data Engineer
The project focused on building a daily predictive model to forecast customer energy consumption for a utilities company using time series analysis.
- Developed PySpark data pipelines to feed input to ML algorithms.
- Built and deployed predictive models using Facebook’s Prophet framework.
- Optimized Spark code to reduce runtime and improve performance.
- Developed and deployed multiple ML models using MLflow.