Lead .NET Engineer (Full-Stack)

CSHARK Sp. z o.o. is seeking a Lead .NET Engineer to join an international project focused on developing and modernising a lending platform used by financial institutions in the UK and Europe.

• Strong commercial experience with C# and .NET Framework 4.x including production application development and maintenance.
• Advanced knowledge of SQL Server and T-SQL, including stored procedures, query optimisation, and agent jobs.
• Hands-on experience with ASP.NET MVC or WebForms and frontend technologies: JavaScript, jQuery, AJAX, Bootstrap.
• Experience in developing and maintaining REST APIs, system integrations, and background-processing services.
• Experience working with complex legacy systems and incremental modernization.
• Previous role as a Tech Lead or Software Architect with architectural decisions, standards, and mentoring.
• Ability to take technical ownership and introduce improvements.
• Practical experience using AI coding assistants (GitHub Copilot, Claude Code, Cursor, OpenAI Codex) including validation of generated code.
• Commercial experience in regulated or financial domains (lending, banking, payments, insurance, consumer credit, collections, KYC/AML).
• Understanding of auditability, change control, data integrity, and compliance requirements.
• Strong analytical and problem-solving skills; proactive and able to work independently.
• Strong written and spoken English (B2+ minimum, C1 preferred).

Nice to have:

• Experience with Delphi 7, COM/COM+, VB, VB.NET, classic ASP, XSLT.
• Knowledge of older Angular applications or SignalR.
• Experience with SOAP/ASMX, Windows Services, RabbitMQ, MSMQ, IBM MQ, XML, EDI.
• Experience migrating applications from .NET Framework to modern .NET.
• Experience in lending, asset finance, consumer credit or debt collection.
• Knowledge of SEPA, UK Direct Debit, card payments, or financial system integrations.
• Familiarity with IdentityServer, ASP.NET Identity, Redis, Adobe Sign, DocuSign.
• Experience with Azure DevOps, TeamCity, or Octopus Deploy.
• Previous experience in a software product company or vendor environment.

• Develop and maintain a complex lending platform using C#, .NET Framework 4.x, ASP.NET, and SQL Server.
• Deliver full-stack changes end-to-end, including requirements analysis, implementation, testing, and code review.
• Develop and optimize T-SQL stored procedures, SQL Server Agent jobs, and database queries.
• Work with ASP.NET MVC, WebForms, JavaScript, jQuery, AJAX, and Bootstrap.
• Maintain APIs, system integrations, and background-processing services.
• Support legacy components including Delphi 7, COM/COM+, and VB.NET where required.
• Improve code quality, system architecture, and maintainability through incremental modernization.
• Utilize AI coding assistants (GitHub Copilot, Claude Code, OpenAI Codex) for development, code analysis, troubleshooting, and documentation.
• Collaborate with developers, business analysts, and stakeholders.
• Take ownership of technical architecture, engineering standards, and product technical direction.
• Mentor engineers and support adoption of AI-assisted development practices.