Senior Python Developer

Locus; Amsterdam; Hybrid; EUR 90,000 - 130,000; Full time

Job summary

Locus is seeking a Senior Python Developer in Amsterdam to join our small team building property management software. You will work on backend features using Python, FastAPI, PostgreSQL, and Redis, turning requirements into robust implementations.

You’ll collaborate with domain experts, write maintainable code with domain-focused tests, and help shape architecture while mentoring colleagues in a fast-paced, product-driven environment.

Qualifications

• Strong experience building and maintaining Python applications, ideally with FastAPI and event sourcing.
• Understanding of relational databases, transactions, backend design, and architectural tradeoffs.
• Collaborative mindset: share thinking, listen, follow through, ask for help.

Responsibilities

• Turn requirements into an implementation, bringing your own ideas to the solution.
• Develop backend features using event sourcing to model business processes and record changes.
• Write maintainable code and domain-focused tests that validate business flows and document how they should work.
• Work with domain experts to validate features, then iterate on their feedback.
• Mentor colleagues and offer guidance on technical decisions, helping the team achieve more together.

Skills

Python

FastAPI

Event sourcing

Relational databases

Tools

PostgreSQL

Redis

Job description

At Locus we're looking for a Senior Python Developer to join our team.

About the company

We're Locus, a small team in Amsterdam building property management software. We know our market, we know what customers need, and we’re ready to build the business. Join us and be part of that journey.

If you enjoy building Python applications, collaborating with colleagues, and taking responsibility for features, we'd like to meet you. You'll work with a lean, structured codebase where event sourcing and CQRS are core to the architecture. You'll focus on backend features, business logic, and data, using Python, FastAPI, PostgreSQL, and Redis.

About the work

Colleagues with real estate expertise are available to explore requirements and work through questions with you. With a shared understanding of the goal and context, you'll have the trust and responsibility to carry the work forward.

• Turn requirements into an implementation, bringing your own ideas to the solution.

• Develop backend features using event sourcing to model business processes and record changes.

• Write maintainable code and domain-focused tests that validate business flows and document how they should work.

• Work with domain experts to validate features, then iterate on their feedback.

• Mentor colleagues and offer guidance on technical decisions, helping the team achieve more together.

  You'll join a team with different strengths and perspectives, with room to deepen your expertise and develop in new directions.
  

  What we'd like you to bring

  • Strong experience building and maintaining Python applications, ideally with FastAPI and event sourcing.

  • A good understanding of relational databases, transactions, backend design, and the tradeoffs behind architectural decisions.

  • Thoughtful collaboration: share your thinking, listen to colleagues, follow through on commitments, and ask for help when you need it.

    If your experience is mainly in Python and event-driven systems, and you're familiar with event sourcing, we'd still like to hear from you. There's room to develop further depth on the job.

    Useful extras

    • Experience integrating cloud AI services, such as Gemini, Claude, or Amazon Bedrock, into application workflows.

    • React experience is a plus, but isn't required. If you're comfortable working on the interface, there's room to contribute there too.

      Practical details

      • You're eligible to work in the Netherlands without requiring sponsorship.

      • 40 hours per week.

      • 25 days of annual leave, plus national holidays.