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

EPAM Systems; Colombia; On-site; COP 167,400,000 - 234,360,000; Full time

Benefits offered by this job

Healthcare benefits

Employee financial programs

Paid time off and sick leave

Upskilling and certification courses

LinkedIn Learning access

Job summary

EPAM Systems is seeking a Senior Full-Stack .NET Developer to tackle modernization and security remediation across legacy and modern .NET environments. You will address vulnerabilities, support legacy Web Forms, MVC, WCF, and ASMX apps, and build RESTful services with ASP.NET Core.

The role requires strong C#, .NET Framework experience, and proficiency with SQL Server, React/Angular/Vue, and secure coding practices. Collaboration with DevOps on secure CI/CD is essential.

Qualifications

• 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.
• English proficiency at an Upper-Intermediate level (B2) or higher.

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.

Skills

.NET

C#

SQL Server

ASP.NET Web Forms

MVC

ASP.NET Core

REST APIs

JavaScript

TypeScript

React

Angular

Vue.js

OWASP Top 10

SAST/DAST

CI/CD

English (B2+)

Tools

TeamCity

Octopus Deploy

IIS

Entity Framework Core

Dapper

Job description

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.ResponsibilitiesInvestigate and remediate application security vulnerabilities, including OWASP Top 10, SAST/DAST findings, SQL injection, XSS, and dependency risksMaintain and modernize legacy ASP.NET Web Forms, MVC, WCF, and ASMX applicationsDevelop and enhance ASP.NET Core Web APIs and modern .NET servicesWork with SQL Server, ADO.NET, EF Core/Dapper, ensuring secure data accessSupport frontend development using HTML, CSS, JavaScript/TypeScript, jQuery, and modern SPA frameworksCollaborate with DevOps to support secure CI/CD and production deploymentsRequirements3+ years of full-stack .NET development experienceExpertise in C#, .NET Framework, and SQL ServerProficiency in ASP.NET Web Forms and MVCBackground in .NET 6/8+, ASP.NET Core, and REST APIsUnderstanding of dependency injectionPractical application security experience and knowledge of OWASP Top 10Experience with React, Angular, or Vue.jsStrong troubleshooting skills and ability to work with large legacy codebasesEnglish proficiency at an Upper-Intermediate level (B2) or higherNice to haveExperience with TeamCity, Octopus Deploy, and IISKnowledge of OAuth2, OIDC, and JWTSkills in HTML, CSS, and jQueryWe offerInternational projects with top brandsWork with global teams of highly skilled, diverse peersHealthcare benefitsEmployee financial programsPaid time off and sick leaveUpskilling, reskilling and certification coursesUnlimited access to the LinkedIn Learning library and 22,000+ coursesGlobal career opportunitiesVolunteer and community involvement opportunitiesEPAM Employee GroupsAward-winning culture recognized by Glassdoor, Newsweek and LinkedInEPAM 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.