Senior Platform Engineer - Polar

Why Polar?

It's never been easier to build, ship, and scale software. But it's never been harder to monetize it.

Modern startups look fundamentally different than prior generations:

• Smaller teams
• Exponential revenue growth relative to headcount
• Higher variability in costs (LLMs) requiring more frequent pricing iterations
• Laser focused on product development and distribution
• Delegating and automating everything that is boilerplate – be it in their codebase or business operations

Exceptional billing primitives, APIs, and SDKs are essential, but delightful integration is not enough. Startups need a billing platform designed for their speed of iteration—combining billing and analytics in one platform to offer customer- and feature unit economics in real-time. Polar offers built-in pricing and cost insights, simulations, and optimizations while handling international compliance, tax management, fraud prevention, and more.

Polar is building the next standard for applied AI startups. Join our small, engineering-led team across Europe as we build infrastructure powering the next generation of software companies.

Role & Responsibilities

We’re hiring a Senior Platform Engineer to architect and evolve the Polar platform—ensuring the system remains fast, resilient, and operationally sound as we scale.

Polar operates as a merchant of record, meaning our platform sits directly in the critical path of global payments, billing infrastructure, and financial workflows. Reliability, uptime, and correctness are essential—while still maintaining the ability to move quickly and ship product improvements.

You’ll work across the platform, application, and infrastructure layers that power Polar—from core infrastructure and observability to shipping new core primitives used within the platform by our customers.

In this role, you will:

• Ensure Platform Reliability & Uptime: Design and evolve systems that maintain high availability, predictable performance, and operational stability. Drive improvements in uptime, resilience, and operational discipline as the system scales.
• Engineer for Scale & Performance: Strengthen how our distributed services behave under load. Identify bottlenecks, optimize critical paths, and design systems that scale with growing traffic and complexity.
• Advance SRE & DevOps Practices: Embed reliability engineering practices across the platform—defining SLOs and SLIs, improving incident response, reducing operational toil, and making production behavior measurable and actionable.
• Evolve Cloud & Infrastructure Systems: Continuously evolve Polar’s infrastructure baseline and determine when the current stack needs to evolve. Improve infrastructure-as-code, environment management, and operational safety mechanisms.
• Strengthen Deployment & Operational Safety: Refine CI/CD systems, rollout strategies, and rollback mechanisms to ensure changes are safe, observable, reversible, and fast to deploy.
• Improve Observability & Debuggability: Advance logging, metrics, and tracing standards so engineers can quickly understand, debug, and resolve issues in production.
• Collaborate across Engineering, Risk & Legal: Work closely with product and infrastructure engineers, as well as risk and legal stakeholders, to translate evolving regulatory requirements into clear technical abstractions while maintaining long-term platform reliability and health.

What We’re Looking For

Systems Thinking & Operating Mindset

• Deep systems thinking: You anticipate failure modes, design for idempotency and consistency, and think carefully about how distributed systems behave in production.
• Security- and compliance-aware engineering mindset: You build with auditability, principled access control, and regulatory constraints as first-order design considerations.
• End-to-end ownership: You are comfortable owning features from infrastructure and backend systems all the way to shipping functionality that powers the product.
• Strong product judgment: You know when to move fast while ensuring that correctness, auditability, and long-term system integrity take precedence.
• High-ownership collaboration: You thrive in small teams, collaborating closely across engineering to evolve the platform architecture.

Technical Skills

• Strong backend expertise designing clear, durable APIs and building systems resilient under real-world load and edge cases.
• Highly proficient in SQL and data modeling with rigorous reasoning about long-term data correctness, performance, and reliability across large datasets.
• Strong production debugging and observability instincts with an ability to trace complex issues across services.
• Experience building or operating distributed systems with strong reliability and operational requirements.

Experience

• 5–8+ years of engineering experience building and scaling customer-facing SaaS or fintech products in a high-growth environment.
• Experience in payments and billing infrastructure (subscription lifecycles, transaction orchestration, refunds/disputes, payouts, and financial state management).
• Nice-to-have: Open source contributions or side projects to showcase.

What We Offer

• Meaningful ownership: Small team & large surface area. You’ll directly influence how the company and platform scale.
• Product-driven culture: We build to empower the next generation of software companies and operate with the same builder mindset internally.
• Competitive compensation: Salary and equity aligned with the impact of the role.
• Remote-first environment: Work from anywhere in Europe, with a home office setup budget available.
• Annual team offsites: Gather in person at least once a year to collaborate, plan, and spend time together.
• Health benefits: Comprehensive health coverage to support you and your family.
• Parental leave: Paid parental leave aligned with local standards and regulations.

Hiring Process

1. Application Review: Review of your application and previous work.
2. Intro Call: Short conversation with Birk (Founder & CEO).
3. Take-home Assignment: Practical exercise reflecting real platform problems.
4. Assignment Review: Review of your assignment and feedback together.
5. Team Conversations: 2–3 video calls to meet future team members.
6. Offer & Reference Calls