Oscar Fernandez
Full Stack Developer · Security Researcher
Experience
Backend Developer & DevOps
Intake · Lanzadera — Valencia (Remote)
- Full design and ownership of the AWS architecture for the MVP: ECS Fargate, ECR, ElastiCache Redis, S3 + CloudFront for frontends, and Secrets Manager; stack selection and architectural decisions made independently.
- Implemented the CI/CD pipeline with GitHub Actions: main branch → pre-production, v* tags → production, covering 10 ECS services across 4 repositories.
- Backend development in FastAPI: domain error system, rate limiting, validation, and observability patterns for production.
- Built integrations with Slack, Microsoft Teams, and WhatsApp Business for the conversational agent.
- Designed and implemented the RAG pipeline (ai_core): embeddings, retrieval, and prompt construction, with final inference on Claude (Amazon Bedrock); function calling and custom tools system for agent orchestration.
Full Stack Developer Intern
Moodest · Lanzadera — Tecnocampus, Mataró
- Developed a REST API with FastAPI integrating with a time-tracking platform with 300,000+ users: authentication, role management, KPIs, and security.
- Built 4 integrations with external channels (Slack, Teams, among others) for the conversational agent, from protocol design to deployment.
- Main developer of the people analytics dashboard (Angular + TypeScript + NestJS): feature implementation, complex user flows, and end-to-end business logic.
- DevOps: containerization with Docker Compose, Nginx configuration on production, and deploy management on own server.
- Agile methodology with Scrum/Kanban, code reviews, and PR management in team.
Education
Vocational Degree in Computer Systems and Networks
Escola Pia Santa Anna, Mataró
Sistemas Microinformáticos y Redes (SMR)
Master's in Programming and Web Development
Frontend: HTML, CSS, JS, React, Next.js. Backend: Python, Django, Flask, FastAPI.
Secondary Education (ESO)
Institut Esteve Albert, Sant Vicenç De Montalt
Complementary Training
Hack4u — Cybersecurity Academy
Offensive Python, Intro to Hacking, Linux administration.
Self-Taught Development & Security Research
Self-directed
3+ years of independent learning across backend engineering, offensive security, and systems programming. Built and published open-source tools in Python and Rust; researched and responsibly disclosed real-world vulnerabilities; hands-on with FastAPI, Docker, Redis, PostgreSQL, MongoDB, CI/CD pipelines, and cloud infrastructure (AWS). Driven entirely by personal projects and curiosity.