Javier Ramirez

Software Engineer

TrueCold

Barcelona, Spain

2024 - Present

• Built and optimized a complex cold chain tracking system:
• Implemented persistent table views with URL-based state management across 9+ data tables (materials, inventory, deliveries, carriers, sensors, etc.).
• Built reusable table components with server-side pagination, filtering, and sorting using TanStack Table.

• Architected and maintained a scalable monorepo structure:
• Designed a Turborepo-based monorepo with multiple apps (backoffice, truecold-app, truecold-api, server) and shared packages.
• Built shared packages for database queries, UI components, type definitions, email service, and logging.
• Implemented consistent TypeScript configuration and ESLint rules across the entire codebase.
• Developed complex database queries with Prisma handling relations, aggregations, and dynamic filtering.
• Created authentication flows and role-based permission systems.
• Built dashboard interfaces for inventory management, sensor monitoring, and delivery tracking.
• Integrated real-time temperature monitoring with TOR (Time Out of Range) calculations and alerts.

• Enhanced developer experience and code quality
• Worked through complex Prisma ORM limitations (e.g., complex relations) and implemented workarounds.
• Applied performance optimizations.
• Fixed critical UX issues.
• Maintained clean separation between server and client components in Next.js 14 App Router.
• Implemented sophisticated URL parameter synchronization for stateful UI components.
• Debugged and resolved TypeScript type issues across a large codebase.

Software Engineer

IEEC - Institut d'Estudis Espacials de Catalunya

Barcelona, Spain

2021 - 2023

Internship

• Contributed to the Gaia4Sustainability outreach project:
• Worked on raising awareness about light pollution and its effects on ecosystems and human life.
• Collaborated with cross-disciplinary teams to translate satellite data into accessible outreach materials and demonstrations.

• Developed hardware and firmware for the FreeDSM initiative:
• Designed and prototyped an affordable, long-lasting device to measure local irradiance for light-pollution studies.
• Integrated sensors, power management and data-logging features to allow distributed deployments and reliable field measurements.
• Implemented data validation and calibration routines to enable comparison with Gaia satellite irradiance products.

• Built data infrastructure, modelling and backend services:
• Implemented a model that estimates irradiance for a given time and place using astronomical parameters and observational metadata.
• Developed Flask-based backends and containerized services (Docker) to collect, store and serve device and model data.
• Created pipelines to compare ground measurements with satellite observations and produce metrics for light-pollution analysis and outreach.
• Wrote documentation, tests and helped maintain reproducible deployments for field teams.

Final Degree Project (Thesis)

Classpip

Barcelona, Spain

2021 - 2021

Final degree project

• Collaborated on the Classpip open-source gamification project:
• Implemented improvements and new features to support classroom gamification scenarios.
• Worked closely with maintainers to submit clean, documented contributions and PRs.

• Designed and implemented a geocaching mode:
• Built geolocation-based gameplay using browser/device geolocation APIs and OpenStreetMap services.
• Integrated map tiles, marker management and route handling to support location-based challenges.

• Delivered supporting work and thesis documentation:
• Implemented front-end logic, UI improvements and performance refinements for the new mode.
• Packaged a demo and deployment-ready assets for evaluation by supervisors and users.
• Thesis (memory) available at: https://errezeeta.github.io/javier.dev/assets/JRM_thesis.pdf