flux-lab.dev
Careers

C# / .NET Backend Developer

Full-time
EngineeringRemote (Europe)

Accounting is our financial platform for small and medium businesses: invoicing, expense tracking, bank synchronization, VAT and exports to 1C/BAS. We're building its next core on .NET and need a C# engineer to own it: the double-entry ledger, the tax and reporting engine, bank and payment-provider integrations, and the background jobs that keep thousands of businesses' books in sync. Correctness matters more than speed here — money math, audit trails and idempotent processing are the daily work. You'll work with the TypeScript frontend team and define the API contract between backend and client.

Requirements

  • 4+ years of production C# and .NET (ASP.NET Core, EF Core or Dapper)
  • Strong PostgreSQL skills: transactions, isolation levels, schema design and migrations
  • Domain modelling for financial data: decimal math, multi-currency, immutable ledgers, audit trails
  • Background processing and reliable messaging (Hangfire, Quartz or MassTransit; RabbitMQ or Redis Streams)
  • REST API design with OpenAPI, versioning and authentication (JWT, OAuth 2.0)
  • Testing culture: xUnit or NUnit, integration tests against a real database, Testcontainers
  • Docker-based deployments on Linux and CI/CD (GitHub Actions)
  • Bonus: bank API or Open Banking integrations, 1C/BAS exports, or Ukrainian tax reporting

Benefits

Fully remote — work from anywhere in Europe
Flexible schedule — async-first culture, no mandatory meetings before noon
$1,500/year professional development budget (conferences, courses, books)
$1,000 equipment allowance for your home office setup
Own the financial core — architecture decisions are yours to make and defend
Small team — your impact is visible from day one
Paid vacation: 20 days + Ukrainian public holidays

Apply Now