Senior Full-Stack .NET Developer (Security & Modernization)

We are looking for a Senior Full-Stack .NET Developer experienced with both legacy .NET Framework and modern .NET (.NET 6/8+). The primary focus is security vulnerability remediation, legacy application support, and modernization.

Responsibilities

• Investigate and remediate application security vulnerabilities, including OWASP Top 10, SAST/DAST findings, SQL injection, XSS, and dependency risks
• Maintain and modernize legacy ASP.NET Web Forms, MVC, WCF, and ASMX applications
• Develop and enhance ASP.NET Core Web APIs and modern .NET services
• Work with SQL Server, ADO.NET, EF Core/Dapper, ensuring secure data access
• Support frontend development using HTML, CSS, JavaScript/TypeScript, jQuery, and modern SPA frameworks
• Collaborate with DevOps to support secure CI/CD and production deployments

Requirements

• 3+ years of full-stack .NET development experience
• Expertise in C#, .NET Framework, and SQL Server
• Proficiency in ASP.NET Web Forms and MVC
• Background in .NET 6/8+, ASP.NET Core, and REST APIs
• Understanding of dependency injection
• Practical application security experience and knowledge of OWASP Top 10
• Experience with React, Angular, or Vue.js
• Strong troubleshooting skills and ability to work with large legacy codebases
• English proficiency at an Upper-Intermediate level (B2) or higher

Nice to have

• Experience with TeamCity, Octopus Deploy, and IIS
• Knowledge of OAuth2, OIDC, and JWT
• Skills in HTML, CSS, and jQuery

We offer

• International projects with top brands
• Work with global teams of highly skilled, diverse peers
• Healthcare benefits
• Employee financial programs
• Paid time off and sick leave
• Upskilling, reskilling and certification courses
• Unlimited access to the LinkedIn Learning library and 22,000+ courses
• Global career opportunities
• Volunteer and community involvement opportunities
• EPAM Employee Groups
• Award-winning culture recognized by Glassdoor, Newsweek and LinkedIn

EPAM is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, age, sexual orientation, gender identity or expression, disability, protected veteran status, or any other characteristic protected by applicable law.