Senior Software Engineer, .NET & WCF Modernization

lseg; Bengaluru; On-site; INR 2,600,000 - 4,200,000; Full time

Job summary

LSEG in Bengaluru is seeking a Senior Software Engineer to support, modernize, and enhance a portfolio of .NET Framework and WCF-based applications. You will lead modernization efforts toward ASP.NET Core Web APIs and cloud-ready architectures, while collaborating with Product, QA, DevOps, and Architecture teams to maintain stability and performance.

The role demands hands-on development, production support, and strong experience in REST APIs, SQL Server, and enterprise integrations, with

Qualifications

• 7+ years of software development experience using Microsoft technologies.
• Strong experience with C#, .NET Framework, and WCF services.
• Experience supporting and enhancing large-scale legacy enterprise applications.
• Knowledge of SOAP, XML, XSD, and service-oriented architectures.
• Experience developing REST APIs using ASP.NET Core or Web API.
• Experience designing and implementing modernization strategies for legacy systems.
• Strong SQL Server experience including stored procedures, query optimization, and performance tuning.

Responsibilities

• Support, maintain, and enhance existing .NET Framework and WCF-based applications and services.
• Diagnose and resolve complex production and application issues across multiple environments.
• Analyze system behavior, logs, and performance metrics to identify root causes and implement fixes.
• Develop new functionality within existing applications while maintaining stability and backward compatibility.
• Participate in on-call support and critical incident resolution activities.
• Document system behavior, integrations, technical dependencies, and support procedures.
• Design, develop, and maintain WCF services supporting internal and external processes.
• Manage service contracts, endpoint configurations, bindings, and authentication mechanisms.
• Develop phased migration strategies from WCF to ASP.NET Core Web APIs and modern architectures.
• Build RESTful APIs supporting modernization initiatives.
• Apply SOLID principles and clean code practices; contribute to architecture discussions.
• Collaborate with architects to align modernization efforts with long-term goals.
• Support CI/CD pipelines and deployment automation; improve release processes.
• Increase automated testing coverage with QA teams.

Skills

C#

NET Framework

WCF

REST APIs

ASP.NET Core

SQL Server

SOAP

XML

Git

Agile

Tools

Git

Job description

Position Overview

The Senior Software Engineer, .NET & WCF is responsible for supporting, enhancing, and modernizing a portfolio of business-critical .NET Framework and WCF-based applications. This role combines hands-on development, production support, technical leadership, and modernization planning to ensure legacy platforms remain stable, secure, and scalable while evolving toward modern .NET and cloud-ready architectures.

The successful candidate will work closely with Product, QA, DevOps, and Architecture teams to maintain existing services, resolve complex technical issues, improve performance, and lead the gradual transformation of legacy applications into modern API-driven solutions.

Key Responsibilities

Legacy Application Support & Enhancement

• Support, maintain, and enhance existing .NET Framework and WCF-based applications and services.
• Diagnose and resolve complex production and application issues across multiple environments.
• Analyze system behaviour, logs, and performance metrics to identify root causes and implement fixes.
• Develop new functionality within existing applications while maintaining system stability and backward compatibility.
• Participate in on-call support and critical incident resolution activities as required.
• Document system behavior, integrations, technical dependencies, and support procedures.

WCF Services & Integration Engineering

• Design, develop, and maintain WCF services supporting internal and external business processes.
• Support SOAP-based integrations and XML messaging frameworks.
• Troubleshoot service communication, security, serialization, and interoperability issues.
• Manage service contracts, endpoint configurations, bindings, and authentication mechanisms.
• Work with business and technical stakeholders to support enterprise integration requirements.
• Ensure integrations remain reliable, secure, and scalable.

Modernization & Migration Initiatives

• Assess legacy applications and identify modernization opportunities.
• Develop phased migration strategies from WCF services to ASP.NET Core Web APIs and modern service architectures.
• Refactor legacy code to improve maintainability, performance, and testability.
• Modernize authentication, authorization, and service communication patterns.
• Support migration efforts from .NET Framework to modern .NET versions where appropriate.
• Evaluate technical debt, prioritize modernization efforts, and recommend implementation approaches.

Application Development

• Develop and maintain applications using C#, .NET Framework, ASP.NET, ASP.NET Core, and related technologies.
• Build and enhance RESTful APIs supporting modernization initiatives.
• Implement secure, maintainable, and scalable software solutions.
• Apply software design principles including SOLID, dependency injection, and clean code practices.
• Contribute to application architecture and technical design discussions.

Database Development & Performance

• Design, develop, and maintain SQL Server database objects including: Stored procedures
• Functions
• Views
• Triggers
• Indexes

Technical Leadership

• Provide technical guidance and mentorship to developers.
• Conduct code reviews and promote engineering best practices.
• Identify technical risks and propose mitigation strategies.
• Assist in establishing development standards and modernization roadmaps.
• Collaborate with architects to align modernization efforts with long-term platform goals.

DevOps & Continuous Improvement

• Support CI/CD pipelines and deployment automation activities.
• Improve build, deployment, and release processes.
• Collaborate with QA teams to increase automated testing coverage.
• Contribute to monitoring, logging, and observability improvements.
• Recommend tooling and process enhancements that improve development efficiency and platform reliability.

Skills & Qualifications

Required

• 7+ years of software development experience using Microsoft technologies.
• Strong experience with C#, .NET Framework, and WCF services.
• Experience supporting and enhancing large-scale legacy enterprise applications.
• Strong understanding of SOAP, XML, XSD, and service-oriented architectures.
• Experience developing REST APIs using ASP.NET Core or Web API.
• Experience designing and implementing modernization strategies for legacy systems.
• Strong SQL Server experience including: Stored procedures
• Query optimization
• Performance tuning
• Database design
• Experience troubleshooting production issues and performing root-cause analysis.
• Strong understanding of software design principles and object-oriented development.
• Experience with source control systems such as Git.
• Experience working in Agile development environments.

Preferred

Experience migrating WCF services to ASP.NET Core Web APIs