Principal Software Engineer

We are looking for a Principal Software Engineer to own the technical direction of our engineering stack and to build in it every day.

This is a hands-on principal role. You will be the most senior engineer on the platform side: a true peer to our senior engineers pairing on hard problems reviewing designs and setting the standard for how we build ship and operate software. At the same time you will own the architectural vision for our services and infrastructure and make sure it stays tightly coupled to where the product is going.

You will work directly with our CTO on technical strategy and with product and business stakeholders on what we commit to and when. We are not looking for an architect who writes documents nor a pure infrastructure specialist. We are looking for the engineer who raises the operational and engineering bar of the whole company and who can be counted on to deliver the hardest piece of work themselves.

What you will own

Architectural vision and technical strategy

• Own the architecture of our service landscape service boundaries contracts data flows real-time serving and evolve it deliberately rather than incidentally.
• Translate the product vision into a technical roadmap: what we build now what we defer what we retire and why.
• Partner closely with the CTO on technical strategy build-vs-buy decisions and cost.
• Write and review designs run architecture sessions and make the trade-offs explicit and documented.

Hands-on engineering:

• Contribute production code continuously this role is expected to be in the codebase not adjacent to it.
• Pair with our senior engineers on hard problems and mentor mid-level engineers through review pairing and design work rather than through a reporting line.
• Take the hardest most ambiguous piece of work yourself when that is what the team needs.

Production and operational excellence

• Own our CI/CD and delivery pipeline: fast safe boring releases; trunk-based automated reversible.
• Own observability end to end metrics logs traces SLOs meaningful alerting so that we detect problems before our partners do.
• Own incident management as a practice: clear on-call structured incident response blameless postmortems and follow-through on the fixes.
• Drive reliability latency and cost as first-class engineering goals for a system embedded in our partners revenue-critical storefronts.

Delivery and stakeholder ownership

• Own delivery commitments with product and business: scope estimate sequence and communicate honestly including when a date will not hold.
• Bring the engineering perspective into product discussions early and represent product reality back into engineering.
• Make decisions with data: instrument what we ship define what better means before building and use production evidence to decide what happens next.
• Think end to end and product first: from problem framing to deployment monitoring and iteration. Shipping is the start of the work not the end.

What we are looking for:

• Substantial experience (typically 8 years) building and operating production software with a clear track record of end-to-end ownership.
• Deep hands-on experience running production workloads on Kubernetes and a major cloud (we are on GCP; equivalent AWS/Azure depth is fine) you have operated real systems not only deployed to a managed platform.
• Proven ownership of observability and incident management: you have personally built monitoring and alerting defined SLOs been on call led incidents and driven the follow-up work. Strong software engineering fundamentals in at least one of our backend languages (Go Python clean tested maintainable code.
• Mature CI/CD practice: automated pipelines automated testing safe rollouts infrastructure as code (Terraform/Helm).
• Data-driven decision making: you define metrics before you build instrument what you ship and change course based on evidence.
• Excellent communication with non-engineering stakeholders. You can explain a trade-off to a product manager or a CEO without diluting it and you handle disagreement directly and constructively.
• Current on industry practice you know what good looks like in 2026 and can bring it in pragmatically rather than wholesale. Fluent English. Based in or relocating to Berlin with at least 3 days/week in the office.

Strong plus

• Experience with low-latency high-volume services (millisecond budgets hundreds of millions of requests per month).
• Working knowledge of TypeScript/React enough to work confidently across our frontend widget though frontend is not the core of this role.
• Experience working alongside data science / ML teams on serving feature pipelines or experimentation.
• Fluency with AI-assisted development (Claude Code Copilot and similar) and an interest in defining how a team uses these tools well.
• E-commerce marketplace or retail technology background. Security and compliance awareness (SOC 2 GDPR) in day-to-day engineering practice.

Required Skills:

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