C# Backend Developer

Company: Quant Capital
Apply for the C# Backend Developer
Location: London
Job Description:

Overview

You will join a small, high-caliber team to build a greenfield trading platform and integrate with external systems. The role sits in a fast-growing fintech environment that values deep technical craft and collaboration. You’ll tackle complex, low-latency problems in distributed .NET architectures and contribute across the product lifecycle. This is a chance to shape critical trading software in a relaxed, open culture with strong learning and growth opportunities.

Pay / Benefits

  • bonus around 20%
  • training budget 750
  • pension
  • life/health insurance
  • flexible working
  • regular social events

Responsibilities

  • Build and improve highly concurrent, event-driven architectures using .NET and C#
  • Develop and maintain APIs and integration points with external platforms
  • Collaborate with a small team and Head of Development to drive product growth
  • Solve complex performance and resiliency challenges in trading software
  • Participate in tech talks, training, and hackathons to continuously improve technology
  • Contribute to design patterns and code quality in a fast-paced fintech environment

Key requirements

  • Degree
  • C# and SQL
  • Experience writing efficient, concurrent .NET code
  • Experience working on distributed systems
  • Knowledge of TCP/IP and websockets
  • WPF, MVC 5, Entity Framework, Web API, Design Patterns
  • collaboration
  • problem-solving
  • continuous learning
  • C#
  • .NET
  • SQL

Posted: September 14th, 2026