C# Senior Backend Engineer, Ukraine, remote in Kalinovskiy Yu.I., FOP

You’ll build and maintain backend services powering a large, data-heavy enterprise platform. This is a hands-on role: schema design, API endpoints, performance/security hardening, and production support—shipping features end-to-end with a small, high-ownership team.

What kind of Features you will work on 
Implementation of personalized news notifications feature

Develop a highly effective subscription management mechanism enabling customers to receive timely updates about significant corporate actions/events affecting assets in their investment portfolios. 

Performance optimization of stock trading services

Conduct thorough profiling and monitoring analysis to identify bottlenecks and critical areas. Apply advanced techniques including caching mechanisms, responsibility redistribution among microservices, and refactoring current code base. Implement automated testing practices along with CI/CD methodologies.

Enhancing system observability across all infrastructure components

Investigate the full lifecycle of customer requests and integrate modern tools to improve observability. Enhance logging systems, robust tracing capabilities, and comprehensive monitoring frameworks. Create user-friendly dashboards providing instant visibility into problem zones and facilitating quick issue resolution.

Integration of AI technologies for risk calculation and compliance control

Design and build infrastructure for seamless interaction with machine learning models aimed at improving risk calculations of investment portfolios and trading compliance control.

Modernization of CRM system using microservice architecture

Migrate the existing CRM solution onto a new microservices architecture based on Clean Architecture principles. This effort will accelerate our company's large-scale transformation program of IT infrastructure.

Development of securities lending microservice

Architect and develop a specialized microservice enabling customers to borrow securities from brokers and financial institutions. Feature should simplify complex reconciliation processes and routine settlements with counterparties.

Responsibilities

• Scoping, architecting, modeling and implementing multiple new product features as you collaborating with front end engineers, UX designers, and founder.
• Getting your hands dirty, writing API endpoints, schemas, data-handling functions, and other code.
• Advising and guiding the evolution of our product roadmap, providing feedback on feasibility and estimated timelines for new feature development.
• Optimize applications for performance, accessibility, and security

Required Experience

• Strong backend experience in C# / .NET
• Strong experience in ASP.NET Core
• Experience with unit testing in .NET
• Experience in SQL
• Knowledge of SOLID principles
• Experience in microservice architecture
• Nice to have (But not required)
  • Knowledge of Clean Architecture principles
  • Experience in buses (like Kafka and Azure Service Bus) and caches (like Redis)

Expectations

We're building mission-critical software for some of the most demanding clients in finance. Here's what that means in practice:

• Ownership over tickets: You'll work within structured sprints, but we expect you to think critically, ask clarifying questions, and take ownership of outcomes — not just check off tasks.
• Delivery-focused culture: We measure success by shipped features and real product impact, not story points or hours logged.
• Full-time commitment: This is a dedicated role requiring 45–50 hours per week. We don't have rigid hours, but expect most work to wrap up by 7 PM your local time. 
• AI-assisted development is expected.

If you're looking for a place where you can grow, ship meaningful work, and be treated as a core part of the team — not just a ticket processor — we'd love to hear from you.