.NET WinForms Developer

CSHARK Sp. z o.o. is hiring a .NET WinForms Developer to join their frontend engineering team working on high-performance, real-time trading applications used by professional traders. The role involves crafting fast, responsive, custom-rendered desktop UIs primarily for trading systems.

• 5+ years of hands-on experience developing desktop applications in C#/.NET (preferably .NET 8).
• Strong expertise in Windows Forms.
• Proven experience building custom UI controls from scratch (inheriting from base controls and implementing custom rendering).
• Experience working with continuous real-time data streams where data is pushed to the UI.
• Strong understanding of multi-threaded UI applications including safe UI updates from worker threads.
• Practical experience in UI performance optimization including reducing redraw cost, minimizing GC pressure, batching updates, and preventing flicker.
• Experience working with TCP / socket-based communication.
• Ability to clearly explain previous UI design decisions and their impact on end users.
• Fluency in English (minimum B2+).

Nice to have:

• Experience with trading systems, market data, or real-time financial applications.
• Familiarity with C++ or interoperability between C# and native components.
• Understanding of high-performance visualization and data interaction patterns.

• Design, implement, and optimize custom WinForms controls (charts, grids, interactive visualization components).
• Work with continuous real-time data streams and ensure ultra-responsive UI under load.
• Ensure smooth multi-threaded UI updates without blocking or freezing.
• Collaborate with backend engineers (C++ systems) to maintain low-latency TCP/socket communication.
• Profile, debug, and tune rendering performance focusing on GC pressure, paint cost, batching, flicker control.
• Improve engineering practices and influence UI architecture and usability.