Staff Software Engineer 100%

You will own:

• Domain model and service boundaries: applying domain-driven design (bounded contexts, aggregates, context mapping) to a real, evolving business domain
• Conceptualize the API layer: contracts, versioning, authentication and authorization, and gateway design, with APIs that developers genuinely enjoy using
• Abstractions that last: defining the abstractions and storage models the platform will grow on as our business logic and expansion needs increase
• Security architecture: IAM, service-to-service authentication, secrets management, and threat modeling as a routine part of design
• Key technical decisions: build vs. buy, migrations, and technology choices, documented as short design docs (ADRs/RFCs) with clear trade-offs
• Critical-path implementation: reference implementations of the hardest components, and reviews of the changes that matter most
• The reliability baseline: observability, failure handling, data consistency (idempotency, retries, event-driven workflows), and an on-call experience that gets better over time

What you bring

This is a senior role. If you have fewer than 10 years of experience, or have not been accountable for architecture decisions, it is not the right role yet.

• 10+ years in software engineering, including at least 4 years as the person accountable for the architecture of a production system
• Deep, practical experience applying domain-driven design to a real system, and the ability to explain where it helped and where it did not
• Strong TypeScript/Node.js, or equivalent depth in another stack with the willingness to work in ours
• Experience designing storage abstractions and data models (PostgreSQL or similar) for scaled backend systems
• Experience designing and operating APIs behind a gateway, including authentication, authorization, rate limiting, and versioning
• Security you have actually applied: least-privilege IAM, service identity, and threat modeling
• Experience designing resilient distributed systems and improving the on-call experience of production systems
• Hands-on experience with AWS and containerized deployments
• Experience with observability in production (logs, metrics, traces, alerting) and an operator’s mindset
• A habit of writing: clear design docs and decisions you can defend
• Fluent English, written and spoken. C1 level or equivalent. English is our working language for design docs, reviews, and daily communication
• Ownership mindset: you believe there is no such thing as “other people’s code”
• The ability to work well with product and engineering colleagues, advocate for what you need, and adjust designs as requirements and feedback change

Nice to have

• Event-driven architecture at scale
• Experience building a platform that other teams build on
• Light frontend exposure (UI work will not be a main part of the role)

Our stack and how we work

• Stack: primarily TypeScript, with Next.js and Tailwind CSS on the frontend, and containers on AWS
• Tooling: use whatever helps you do your best work, including Claude Code and other AI tools
• Language: English first for all documentation, meetings, and written decisions
• Async-first, with written decisions
• Engagement: contractor (B2B), paid in EUR, with a competitive rate for the seniority of the role

How to apply

Please do not just upload a CV. Send your CV together with short written answers in English (about 300 words each) to the following two questions:

1. Describe a system whose architecture you owned. What was the hardest trade-off you made, and what would you change today?
2. Describe a case where a domain boundary you drew turned out to be wrong. How did you find out, and what did it cost to fix?

What you get

• A competitive rate in EUR, matched to the seniority of the role and protected from local currency swings
• Real ownership. You shape the architecture of a platform from day one, and your decisions stay in the product
• A fast-growing company. properti is growing quickly, so your scope and influence can grow with it
• Direct access to decision-makers, a small senior team, and a say in the roadmap
• Freedom in how you work. Remote, flexible hours, and the tools you choose, including AI tools like Claude Code