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Sergio Sánchez RamírezSS

Sergio Sánchez Ramírez

Senior Python Developer | Django | REST API | AWS

€390/day
Santa Cruz de Tenerife, ES
15+ years

Average response time: 1 hour

About Sergio

I help companies build and improve their backend systems: APIs, integrations, data pipelines, and internal tools. My focus is Python (Django, FastAPI, Flask), and I bring 20 years of experience turning business requirements into working, maintainable code.

Typical projects I take on: building new features for existing platforms, integrating third-party services (CRMs, payment providers, external APIs), designing data flows between systems, and improving performance or reliability of current codebases.

I've worked across travel-tech, healthcare, e-commerce, and SaaS. This means I'm comfortable ramping up quickly in different domains and understanding what actually matters for the business.

I work well with distributed teams and async communication. Clear documentation, proactive updates, and predictable delivery are part of how I operate.

Available for contract engagements, both short-term projects and longer collaborations.
  • Spanish

    Native or bilingual

  • English

    Fluent

  • Catalan

    Fluent

  • French

    Basic

Can work on-site
Santa Cruz de Tenerife (up to 50km), Barcelona (up to 20km)

Experience

  • Maarlab
    Senior Python Engineer
    TRAVEL AND TOURISM
    March 2025 - December 2025 (9 months)
    Santa Cruz de Tenerife, Spain
    Developed backend microservices for a travel-tech platform enabling hotels to sell flight+hotel packages directly, competing with traditional OTAs. Designed and implemented the financial settlement system handling complex commission flows between customers and hotels, including payment cycle management
    with state machines and domain events.

    Built a dynamic flight filtering engine to optimize search results quality with Redis synchronization for distributed rule management. Applied Clean Architecture and domain-driven design patterns with emphasis on testability, service integration, and structured logging for observability. M
    FastAPI Microservices Clean Architecture Domain Driven Design Python (Programming Language)
  • Panora
    Senior Python Engineer
    E-COMMERCE
    September 2024 - November 2025 (1 year and 2 months)
    Built backend features for a Customer Success SaaS platform using Django REST Framework. Integrated HubSpot CRM data via Nango synchronization layer, handling deals, contacts, companies, and pipeline stages without custom OAuth infrastructure.

    Contributed to service-oriented architecture design and implemented background processing with Celery for data updates and historical backfills. Emphasis on comprehensive test coverage throughout.


    Part-time engagement during overlap with other contracts.
    Django API REST AWS Celery
  • IQVIA Spain
    Senior Python Engineer
    HEALTH AND WELLNESS
    November 2023 - June 2024 (7 months)
    Barcelona, Spain
    Contracted as sole developer to maintain and evolve a Clinical Terminology Server for healthcare data standardization, during its acquisition by IQVIA. Developed new features and ensured interoperability with other applications through APIs and background tasks.

    Helped align the product with IQVIA's internal standards and project requirements.

    Led the hiring process for the permanent position, including candidate evaluation, onboarding, and knowledge transfer.
    Django API REST Amazon Web Services (AWS) Python (Programming Language)

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Education

  • Ingeniería Técnica en Informática de Sistemas
    Universidad de La Laguna
    2001
    Ingeniería Técnica en Informática de Sistemas

Skill set

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