Senior Backend Developer

Overview

We are seeking a highly experienced Senior .NET RESTful API Developer with deep expertise in ASP.NET Core on .NET 10 to design, implement, and operate high-performance, secure, and scalable RESTful APIs
.

This role is API-first and focuses on building backend platforms that serve web, mobile, and third-party clients. The ideal candidate has an advanced understanding of HTTP, REST principles, API versioning, security, performance, and lifecycle management
, combined with strong C# and T-SQL skills and real-world experience hosting APIs on IIS
.

RESTful API Design & Development (Primary Responsibility)

• Design and implement RESTful APIs using ASP.NET Core (.NET 10)
• Define and enforce REST standards
  :
• Proper HTTP methods and status codes
• Resource-oriented API design
• Idempotency and statelessness
• Implement API versioning strategies and backward compatibility
• Design clean, consistent request/response contracts (DTOs)
• Handle pagination, filtering, sorting, and searching efficiently
• Implement robust input validation, error handling, and exception mapping
• Produce and maintain API documentation (OpenAPI / Swagger)
• Optimize APIs for high throughput and low latency
• Ensure APIs are secure, reliable, and maintainable throughout their lifecycle

• Write high-quality, performant, and maintainable C# code
• Apply Clean Architecture / DDD principles to API-centric systems
• Design efficient data access layers using EF Core and Dapper
• Write and optimize T-SQL queries, stored procedures, and functions
• Implement JWT-based authentication and claims-based authorization
• Deploy and manage REST APIs on Microsoft IIS
• Configure IIS application pools, bindings, SSL, and environment settings
• Diagnose and resolve API performance and production issues
• Participate in code reviews and enforce API design standards
• Mentor team members on RESTful API best practices

• Expert knowledge of ASP.NET Core (.NET 10) for REST APIs
• Deep understanding of:
• HTTP protocol and semantics
• Middleware pipeline and filters
• Model binding and validation
• Strong experience with Minimal APIs and Web APIs
• Strong experience designing APIs consumed by SPAs and mobile apps
• Advanced C# expertise
  , including:
• async/await and concurrency
• Memory management and GC behavior
• Value vs reference types
• Records, immutability, and performance-aware coding
• Strong understanding of the .NET 10 runtime and BCL

Databases & T-SQL

• Strong experience with SQL Server
• Advanced T-SQL skills:
• Query tuning and execution plans
• Indexing strategies
• Transactions and isolation levels
• Efficient use of Entity Framework Core for APIs
• Experience with Dapper for performance-critical API endpoints

API Security

• JWT-based authentication
• Claims-based and policy-based authorization
• Secure API design following OWASP API Security Top 10
• Experience integrating external identity providers (Azure AD or similar)

IIS & API Hosting

• Strong experience hosting ASP.NET Core REST APIs on IIS
• Application pool tuning and request handling
• HTTPS, certificates, and bindings
• API logging, diagnostics, and monitoring on Windows Server

Dev Ops & Delivery

• CI/CD pipelines using Azure Dev Ops or Git Hub Actions
• Deployment to Azure and/or AWS
• Environment configuration and secrets management

Soft Skills

• Strong API-centric problem-solving mindset
• Clear communication of technical API concepts
• Ownership of API quality and stability
• Ability to mentor developers on REST standards and backend best practices
• High attention to detail and consistency

Qualifications

• Bachelor’s degree in Computer Science or equivalent experience
• 5+ years building production-grade RESTful APIs in .NET
• Proven experience designing APIs used by real-world clients