Senior .NET Full-Stack Engineer—Security & Legacy Modernization

EPAM Systems; Colombia; On-site; COP 223,864,000 - 351,786,000; Full time

Benefits offered by this job

Healthcare benefits

LinkedIn Learning access

Global career opportunities

Paid time off and sick leave

Upskilling and certification courses

Job summary

EPAM Systems in Colombia seeks a Senior Full-Stack .NET Developer to remediate security vulnerabilities, support legacy applications, and modernize services across .NET Framework and .NET 6/8+. You will work across backend, data, and frontend while partnering on secure delivery.

Responsibilities include investigating and remediating OWASP Top 10 findings, hardening against SQL injection and XSS, building ASP.NET Core APIs, and collaborating with DevOps on secure CI/CD pipelines and production

Qualifications

• 3+ years of full-stack .NET development experience.
• Strong leadership and ownership to drive remediation and modernization work.
• C# and .NET Framework expertise including ASP.NET MVC and Web Forms.
• REST API development with ASP.NET Core (6/8+).
• Microsoft SQL Server and ADO.NET for secure data access.
• Upper-Intermediate English (B2+).

Responsibilities

• Investigate and remediate application security vulnerabilities across OWASP Top 10 and automatic findings.
• Harden applications against SQL injection, XSS, and dependency risks.
• Maintain and modernize legacy .NET Framework apps (ASP.NET Web Forms, MVC, WCF, ASMX).
• Build and enhance ASP.NET Core Web APIs and modern .NET services.
• Collaborate with DevOps to support secure CI/CD pipelines and deployments.
• Troubleshoot production issues and deliver timely fixes with minimal risk.
• Review code changes for security and maintainability.
• Document remediation decisions for future maintenance.

Skills

Full-stack .NET development

Leadership

C#

JavaScript

REST API

English (B2+)

Problem solving

Tools

ASP.NET MVC

ASP.NET Web Forms

WCF

ASP.NET Core

ADO.NET

SQL Server

Job description

EPAM Systems in Colombia seeks a Senior Full-Stack .NET Developer to remediate security vulnerabilities, support legacy applications, and modernize services across .NET Framework and .NET 6/8+. You will work across backend, data, and frontend while partnering on secure delivery.

Responsibilities include investigating and remediating OWASP Top 10 findings, hardening against SQL injection and XSS, building ASP.NET Core APIs, and collaborating with DevOps on secure CI/CD pipelines and production