Senior C#/.NET Developer – WPF UI | FinTech | Low-Latency Systems

# Senior C#/.NET Developer – WPF UI | FinTech | Low-Latency Systems **Location:** Delhi / Gurgaon / NCR, India **Initial Onsite Requirement:** Gurgaon – minimum 1 month **Engagement:** Contract / Part-Time or Full-Time – depending on fit **Experience:** 5+ years ## About the Role We are looking for a **Senior C#/.NET Developer with strong hands-on WPF/UI development experience** to join an ongoing technology project. This is **not a greenfield project**. You will be joining an established application and development team, so you should be comfortable understanding an existing codebase, architecture and business logic and becoming productive quickly. The role is particularly suited to someone with strong **C#/.NET + WPF + XAML** experience. Experience in **FinTech, Capital Markets, Trading, Banking or other financial applications** is a strong advantage. Experience with **low-latency, high-performance or real-time systems** will be highly valued. ## Important Location Requirement You **must be based in Delhi/Gurgaon/NCR** and be able to work from our **Gurgaon office for at least the initial one-month onboarding period**. The purpose of this initial onsite period is to ensure you become familiar with the existing application, architecture, business requirements, development processes and team workflows. Once you are fully familiar with the project and the team is comfortable with the transition, the longer-term working arrangement can be discussed. **Please do not apply if you are unable to meet the initial Gurgaon onsite requirement.** ## What You'll Be Doing * Develop and enhance an existing C#/.NET application. * Understand and work within an established codebase and architecture. * Develop and maintain **WPF-based desktop UI using C# and XAML**. * Work with data binding, commands, MVVM and reusable UI components. * Build responsive, reliable and maintainable user interfaces. * Develop new features and enhance existing functionality. * Troubleshoot, debug and resolve application-level and UI issues. * Analyse performance issues and contribute to application optimisation. * Participate in code reviews and maintain high code quality. * Work closely with developers, product/business stakeholders and other team members. * Perform unit testing, functional testing and regression testing. * Reproduce reported issues, identify root causes and validate fixes. * Ensure new functionality does not negatively impact existing functionality. * Document technical changes and functionality where required. ## Required Technical Skills Strong hands-on experience with: * **C#** * **.NET / .NET Framework** * **WPF** * **XAML** * Object-Oriented Programming * Design Patterns * SOLID principles * Multithreading / asynchronous programming * LINQ * REST APIs / Web Services * SQL / relational databases * Debugging and performance optimisation * Unit testing * Git or other source-control systems ### WPF/UI Experience is Essential This is a **WPF-heavy role**, so strong practical experience is essential. You should be comfortable working with: * XAML * Data Binding * Commands * MVVM * Custom Controls * UI Performance Optimisation * Complex Desktop Applications * Reusable UI Components * UI and application-level debugging ## FinTech / Capital Markets Experience – Major Advantage Experience working on: * FinTech applications * Capital Markets * Trading systems * Banking applications * Financial Services * Market data applications * Order Management Systems * Risk systems * Transaction-intensive applications will be a strong advantage. ## Low-Latency / High-Performance Experience – Strong Advantage Candidates with genuine experience in performance-critical systems will be preferred. Relevant experience includes: * Low-latency systems * High-throughput applications * Multithreading and concurrency * Memory optimisation * Performance profiling * Efficient data structures and algorithms * Real-time data processing * High-frequency or near-real-time financial applications This is **not mandatory**, but it will be a significant differentiator. ## Testing & Quality Ownership This role is not limited to development. You will also be expected to take ownership of the quality of the code you deliver, including: * Unit testing * Functional testing * Regression testing * Reproducing reported issues * Debugging defects * Validating fixes * Working with testers/business users * Ensuring new changes do not break existing functionality We are looking for someone who takes ownership of the quality of their work rather than simply handing development work over to QA. ## What We're Looking For The ideal candidate is: * A strong hands-on C#/.NET developer. * Highly experienced in WPF/UI development. * Comfortable working with an existing and potentially complex codebase. * Strong in debugging and problem-solving. * Comfortable working independently. * Detail-oriented and quality-conscious. * Able to take ownership of modules/features. * Comfortable collaborating with an established development team. * Able to understand business requirements and translate them into technical solutions. * Comfortable working across both development and testing. * Able to learn an existing product and business domain quickly. ## Why Join This Project? You will be joining an **ongoing real-world technology project** rather than working on a small standalone assignment. The application involves technically challenging areas where **performance, reliability, UI quality and business functionality** are important. Candidates with FinTech, Capital Markets and low-latency experience will have the opportunity to work on particularly interesting technical challenges. ## To Apply Please include the following in your proposal: 1. Total years of C#/.NET experience. 2. Total years of WPF experience. 3. A brief description of your WPF/XAML/MVVM experience. 4. Details of any FinTech, Capital Markets, Trading or Banking applications you have worked on. 5. Details of any low-latency or high-performance systems you have worked on. 6. Your experience with testing and debugging. 7. Your current location in Delhi/NCR/Gurgaon. 8. Confirmation that you can work from our Gurgaon office for the **initial one-month onboarding period**. 9. Your current availability and notice period. 10. Your expected hourly/monthly rate. **Please provide specific examples of relevant projects rather than generic descriptions of your experience.** We are particularly interested in candidates who can demonstrate strong **C# + WPF + XAML/MVVM + desktop UI development** experience. FinTech and low-latency experience will be a major advantage.