# David Marcos (@noz.am)

Profile: https://sifa.id/p/noz.am
Headline: Senior Software Engineer

## Career

- **Senior Software Engineer at United Nations** (Oct 2023 - Dec 2025)
  • Built modular React + TypeScript frontends and reusable UI components for analyst workflows.
  • Developed advanced D3.js force graph visualizations for investigative analysis (zoom/pan, filtering, highlights).
  • Designed and secured backend APIs using Flask, PostgreSQL, and graph DB integrations with OIDC + JWT + RBAC.
  • Improved system performance through ORM optimization, indexing, caching, and query tuning.
  • Implemented unit tests (pytest) and UI tests (Selenium) integrated into CI/CD.
  • Containerized and deployed systems across DEV/QA/PROD using Azure DevOps.
  • Implemented platform-wide i18n with locale routing and translation workflows.
- **Realtime Data Engineer at Citymapper** (May 2021 - Sep 2023)
  In Citymapper I worked mainly on integrating and maintaining data pipelines for real time transport data, mainly related to public transport in different cities and countries.
  
  I have also had to work on infraestrucure as a code, deployments and creating APIs.
  
  I have worked with Python (flask, pandas...), AWS (EC2, Lambda, Cloudwatch, DynamoDB...), and Grafana/InfluxDB for reporting, and Docker.
- **Software Developer at Newtral** (Apr 2019 - May 2021)
  At Newtral.es, I worked in a variety of projects, from tools that help journalists on their daily work, to data analysis and visualization for data journalism projects, where I was able to work with journalists. This work was related to fighting misinformation in Spain. I developed APIs for internal tools using Flask and FastAPI on Python. I also collaborated with the ML team, where I used libraries like Pandas and Scipy. My work was related to the data pipelines used for the models, and deploying models as APIs.
- **Junior Backend Developer at TherapyChat** (Nov 2018 - Apr 2019)
  I was able to learn what would be the basic skills I would need in my professional career, helping build a welcome chat bot for the main company's service, using mainly Python and SQL. I also got to work with Django.

## Skills

### Technical
- Android Studio
- AWS
- D3.js
- Docker
- Eclipse
- GCP
- Git
- Linux
- MySQL
- Python
- React.js
- SQL
### Other
- Azure DevOps Server
- Empresas de nueva creación
- Flask
- Mantenimiento de datos

## Credentials

- Python for Data Science — Coursera (Aug 2018) https://www.coursera.org/account/accomplishments/verify/9WSUNV2BFVQA
- Data Visualization with Python — Coursera (Aug 2018) https://www.coursera.org/account/accomplishments/verify/MC96KUQSFHGN

## Education

- **Universidad Carlos III de Madrid** — Grado en Ingeniería (2016 - 2017)
  Activities & Societies: Comisión TIC UC3M, Volunteer at T3chFest

## Involvement

### Volunteering
- T3chFest (Oct 2017 - Oct 2018)
  Organizer

## Links

- linkedin: https://www.linkedin.com/in/dmarcosm