Senior .NET / C# Developer – Enterprise API & Platform Integration

Turnkey Learning; Hyderabad; On-site; INR 1,800,000 - 2,400,000; Full time

Job summary

Turnkey Learning is seeking a Senior .NET / C# Developer to design and build scalable backend services for enterprise-grade APIs and platform integrations. You will work on REST APIs, cloud-native components, and secure integrations across retirement, payroll, HRIS, and benefits ecosystems.

The ideal candidate has 5+ years of experience with .NET technologies, API design, SQL Server, and modern cloud deployments.

Qualifications

• 5+ years of experience building enterprise-grade backends and REST APIs.
• Strong expertise in .NET, API development, cloud integrations.
• Experience with secure auth (OAuth2/OpenID Connect) and JWT.
• Domain experience in retirement, payroll, HRIS, or benefits integrations.
• Familiar with SaaS platforms and microservices architectures.

Responsibilities

• Design and develop scalable backend apps using C#, .NET Core/.NET 8.
• Build and maintain RESTful APIs and middleware for enterprise integrations.
• Integrate with retirement, payroll, HR and benefits platforms.
• Implement secure authentication using OAuth2, JWT, OpenID Connect.
• Implement asynchronous processing, event-driven workflows, microservices.
• Design/optimize SQL Server and PostgreSQL data models and access layers.
• Participate in cloud deployments, CI/CD, monitoring, production support.
• Collaborate with product managers, architects, QA, DevOps, client teams.

Skills

C#

.NET Core / .NET 6-8

ASP.NET Core Web API

Entity Framework Core

API & Integration

REST APIs

Swagger/OpenAPI

JSON/XML

OAuth2/OpenID Connect

Webhooks & Integrations

Postman/API Testing

SQL Server

Query Optimization

Stored Procedures

Transaction Processing

Tools

Docker

GitHub / GitHub Actions

Job description

Senior .NET / C# Developer – Enterprise API & Platform Integration

Seeking a Senior .NET / C# Developer with 5+ years of experience building enterprise-grade backend systems, REST APIs, and cloud-native integrations. The role focuses on developing scalable SaaS platforms and secure integrations similar to retirement administration, financial services, payroll, and benefits platforms such as Relius API Platform .

The ideal candidate will have strong expertise in .NET technologies, API development, cloud services, secure integrations, and transactional enterprise systems.

Qualifications

• C#
• .NET Core / .NET 6/7/8
• ASP.NET Core Web API
• Entity Framework Core
• API & Integration
• REST APIs
• Swagger / OpenAPI
• JSON/XML
• OAuth2 / OpenID Connect
• Webhooks & API Integrations
• Postman/API Testing
• Database Technologies
• SQL Server
• Query Optimization
• Stored Procedures
• Transaction Processing
• Docker
• GitHub / GitHub Actions
• Preferred Skills
• Redis Caching
• Financial or Retirement Domain Experience
• Payroll / HRIS / Benefits Integrations
• SaaS Platform Development
• Functional Domain Experience Preferred
• Retirement Administration
• Insurance & Benefits Administration
• Payroll Systems

Responsibilities

• Design and develop scalable backend applications using C#, .NET Core/.NET 8, and ASP.NET Core Web APIs
• Build and maintain RESTful APIs, middleware, and enterprise integrations
• Integrate with retirement, payroll, HR, financial, and benefits administration platforms
• Develop secure authentication and authorization frameworks using OAuth2, JWT, and OpenID Connect
• Implement asynchronous processing, event-driven workflows, and microservices architectures
• Design and optimize SQL Server/PostgreSQL databases and data access layers
• Participate in cloud deployments, CI/CD automation, monitoring, and production support
• Collaborate with product managers, architects, QA teams, DevOps engineers, and client integration teams