Backend (Python) Software Engineer - Calvin Risk team

2 weeks ago


Belgrade Novi Sad Nis, Serbia Holycode Full time €60,000 - €80,000 per year
Backend (Python) Software EngineerCalvin Risk

About the job

Calvin Risk is a Swiss-based start-up helping companies create and manage trustworthy AI that is aligned with humanity. Founded in 2022 as an ETH Zurich spin-off, the company is building the most advanced platform for assessing risks associated with AI in commercial use and managing them throughout the entire product lifecycle. The Calvin platform creates a much-needed framework for transparency, governance, and standardization for enterprises to manage their AI portfolios while ensuring that AI remains safe and compliant with the highest ethical standards and impending regulatory requirements.

In this role, you'll be part of a small, dynamic team where your work will directly contribute to the development of a platform designed to shape the future of AI governance. You'll work on interesting problems, develop critical backend systems, and grow alongside the company as we scale.

What You'll Do:

  • Architect and develop a polished Python SDK that wraps our APIs—packaged and published (e.g., PyPI) with clear versioning.
  • Create utility CLI tools, helper libraries, and integration examples to streamline adoption.
  • Design, develop, and maintain robust and scalable APIs to support the Calvin platform and its integrations with internal and external services.
  • Author thorough documentation, code samples, and tutorials to onboard new users.
  • Work with CI/CD pipelines and DevOps tools like Docker and Kubernetes to support deployment processes and make small adjustments when necessary.
  • Monitor production systems and SDK usage metrics to ensure uptime and performance

What We're Looking For:

  • Proven track record building and maintaining client-side libraries or SDKs—packaging, versioning, and publishing to PyPI.
  • Proven expertise in backend software development, particularly in API development and data processing, using Python and frameworks like Flask, FastAPI, or Django.
  • Familiarity with DevOps tools like Docker and CI/CD pipelines, with a willingness to learn and adapt.
  • A thoughtful, results-driven approach to solving technical problems.

Why Calvin Risk?

  • Purpose-driven work: Your contributions will help build a platform focused on making AI safer and more accountable.
  • Creative Ownership: You'll work on the full system, from architecture to core features, with the freedom to shape how things are built.
  • Growth: As a growing start-up, you'll have the opportunity to grow alongside the company and take on increasing responsibilities.
  • Inclusive Culture: We value respect, integrity, and collaboration. Everyone's input matters, and we foster a supportive, inclusive environment.

We follow the REEEEF principle as our guideline to success: respect, efficiency, entrepreneurship, excellence, empathy, fun. We cherish character traits such as result orientation, a sense of responsibility, integrity, and passion. This is an a**hole-free zone and it shall remain that way. Apart from this, no matter who you are or where you are from, you are highly welcome at Calvin Risk

Why you'll love working here:

  • Private health insurance
  • Flexible work model – full remote or hybrid
  • Equipment of your choice (laptop, monitor, accessories)
  • High-growth company with innovative products
  • Supportive, international team
  • Budget for professional development (courses, books, conferences)
  • English and German language lessons during working hours
  • Nice office in Belgrade with a stocked kitchen and game area
  • Opportunity to learn, grow, and make a real impact

If you are looking for an environment where you can grow professionally, learn from the best in the field, balance work and life habits and have a pleasant and enthusiastic environment, please submit your CV in English.

#LI-hybrid



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