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Guillaume SantoroGS

Guillaume Santoro

Backend Software Engineer

€540/day
Perpignan, FR
3-7 years

Average response time: 1 hour

About Guillaume

I’m a highly skilled and passionate Backend Software Engineer with over 7 years of professional experience in building robust and scalable applications. I specialize in backend systems development, particularly using Java, and have worked extensively with modern frameworks and tools such as Spring Boot, Python, Docker, and NGINX.

Currently, I work as a freelancer, providing tailored solutions to clients by designing and developing APIs, microservices, and backend infrastructure that optimize business operations. My focus is on delivering clean, secure, and reliable code with a strong emphasis on performance and maintainability.


Key Skills:
Backend Development: Java (Spring Boot, Hibernate), Python
Microservices & API Design
Cloud Infrastructure: AWS (EC2, Lambda, RDS, DynamoDB)
DevOps: Docker, Terraform, Jenkins
Databases: MongoDB, PostgreSQL
Tools: Git, JIRA, Confluence, CircleCI


Whether you're looking to build a new system from scratch or improve an existing one, I can help you achieve your goals with solutions that are designed to scale with your business needs.
  • French

    Native or bilingual

  • English

    Fluent

  • Spanish

    Fluent

Can work on-site
Perpignan (up to 50km)

Experience

  • Opengamma
    Backend Software Engineer
    January 2021 - December 2025 (4 years and 11 months)
    Implemented sophisticated margin model to calculate margin requirements, enabling clients to optimize margin usage, forecast treasury needs and ef fectively manage financing risks. Ensured code quality and test coverage contributing to secure and reliable systems.
    Développement Back-End Java
  • ISAM Funds,
    Full Stack Engineer (Systematic Trading)
    January 2020 - January 2021 (1 year)
    London, UK
    Development of trading systems and tools. Monitoring and executing IRSs, CDSs or NDFs. Rich financial environment with 300+ markets traded. 14, PostgreSQL, JUnit, Mockito, Maven
  • BNP Paribas Arbitrage,
    Full Stack Engineer (Risk & PnL)
    January 2018 - January 2020 (2 years)
    London, UK
    Development of several tailor-made tools for trading in a global risk manage ment application. Production responsibilities on Risk & PnL.

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Education

  • IBM AI Engineering
    Coursera
    2025
    IBM AI Engineering
  • Ingénieur en Informatique et Mathématiques Appliquées
    ENSIMAG
    2018

Skill set

Categories