Senior Software Engineer (Backend)

In this role, you willWe are looking for a Senior Backend Software Engineer passionate about building reliable, scalable integrations with third-party systems. Subsets integrates with many external APIs from major CRM and marketing platforms, including HubSpot, Braze, and Sailthru. You'll own and develop new features from conception to deployment, ensuring reliability and scalability across our integration ecosystem. This includesBuild and maintain backend services that integrate with third-party CRM APIs.Implement and improve data sync processes between our system and external CRMs.Improve Subsets’ depth of integrations with third-party CRM APIs to unlock additional functionality for our customers.Ensure integrations are reliable and data stays correct by adding proper validation, monitoring, and error handling.You may be a good fit if you have(Required) Proficiency with .NET and Entity Framework Core.(Required) Experience with building and maintaining robust 3rd party api integrations.Experience with DDD.Experience with event-driven data architecture.PostgreSQL (or general SQL) expertise.Experience with Google Cloud Platform.Familiarity with Claude Code or other coding agent tools.Strong bias toward action and self-direction with the ability to work autonomously without much oversight.Anti-meeting culture mindset.This is neither an exhaustive nor a necessary list of capabilities. If none of these apply to you, but you believe you can contribute to Subsets, please reach out.How We WorkOur tech stackBackend: .NET 10, Entity Framework Core, PostgreSQL, Hangfire, Redis.Frontend: React.js, Vite, Tailwind CSS, shadcn/ui.Infrastructure & CI/CD: Google Cloud Platform (GCP), Terraform, GitHub Actions.Lightweight and efficient development cultureIssue tracking and planning via Linear2-week sprintsAnti-meeting culture - we value focused work timeBenefitsCompetitive salaryEquity package: 0.2%-0.4% (favorable taxation under §7p, read: no upfront tax on your options!)Company card for all things food/snacks: order whatever office snacks you like (we frequently get mango smoothies, protein drinks, barbells, monster, etc.)Great breakfast and lunch (and dinner when working late in the office)Office kayaks 🛶About the interviewWe will typically meet three times:For an introductory coffee in our Copenhagen office,For an in-depth technical interview, andFor a 2 day work trial.