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Jan KeijzerJK

Jan Keijzer

Senior Software Engineer & Tech Lead

€800/day
Heerde, NL
15+ years

Average response time: 1 hour

About Jan

30 years of building production systems. I enter where technical foundation is missing and build what's needed — architecture, backend, APIs, infrastructure.

What I've delivered:

  • A SaaS platform from zero to acquisition (several million euros)
  • A 24/7 healthcare alarm system scaled from hundreds to thousands of devices, zero downtime
  • Real-time simulation software for ESA spacecraft
  • One of the first Dutch online banking portals (ABN AMRO, 1995)
Available for: technical lead, solution architect, senior backend developer. I work best on projects that need someone who sees the full picture — not just code, but architecture, scalability, and delivery.

Stack: Python, FastAPI, PostgreSQL, Docker, CI/CD. AI-augmented development as standard practice.

PhD Reactor Physics, TU Delft.
  • Dutch

    Native or bilingual

  • English

    Fluent

Remote only
Primarily works remotely

Experience

  • Imperial Automation
    Owner / Senior Software Engineer
    DIGITAL AND IT
    January 2026 - Today (5 months)
    Heerde, Netherlands
    Independent consultant specialising in technical architecture and AI-powered system development.
    • • Built open source developer tooling that automates AI-augmented development workflows
    • • Built node-based AI workflow orchestration for automated content pipelines
    • • Implemented prompt tracking and evaluation for monitoring AI output quality
    • • Designed and built a full dating platform from scratch: FastAPI, PostgreSQL, Redis, Docker, AI-driven content moderation Stack: Python, FastAPI, LLM APIs, Pydantic, Docker, PostgreSQL, TypeScript, PHP, CI/CD
    Python FastAPI PostgreSQL Docker LLM
  • Zintouch
    Lead Developer
    DIGITAL AND IT
    January 2019 - January 2025 (6 years)
    Heerde, Netherlands
    Joined as first software engineer on a 24/7 social alarm platform for life-critical healthcare situations. Together with the CTO, professionalised the product while it had to keep running around the clock.
    • • Transformed an ad-hoc codebase into structured architecture with CI/CD and version control
    • • Executed zero-downtime server migration without a single lost alarm
    • • Scaled from hundreds to thousands of connected devices across multiple tenant organisations
    • • Co-responsible for company growth from 6 to 50+ employees
    • • Contributed to ISO certification process Tech: PHP, MySQL, Yii2, JavaScript, Docker, Jenkins, Linux
    PHP MySQL Docker Jenkins Linux
  • Connected Care
    Lead Developer
    DIGITAL AND IT
    January 2017 - January 2019 (2 years)
    Heerde, Netherlands
    Tech lead on EU-funded healthcare innovation projects across multi-country consortia. Managed rotating development teams across international partners. Coordinated technical deliverables across organisations with different capabilities and priorities. Navigated the intersection of technology, healthcare regulation, and multi-stakeholder governance.
    Java Spring Angular MySQL React Native

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Education

  • PhD
    (TU Delft).
    PhD
  • PhD
    Delft University of Technology
    1996
    PhD

Certifications

Skill set

Categories