Backend C#/.NET Developer

What you would do

• Design and implement backend services and REST APIs using C# and .NET frameworks
• Write clean, maintainable code with comprehensive documentation and clear architectural patterns
• Build efficient MySQL database schemas and write optimized queries for data access
• Troubleshoot and resolve backend issues quickly in production and staging environments
• Optimize existing systems for performance and scalability without breaking deployments

Who they want

• Advanced expertise in C# and the .NET ecosystem, with strong understanding of asynchronous programming and dependency injection patterns
• Strong experience with MySQL database design, schema optimization, and query performance tuning
• Solid understanding of RESTful API design patterns, integration approaches, and secure coding practices
• Demonstrated history of producing clean, maintainable code with comprehensive technical documentation
• Strong communication skills and capacity for self-directed work in distributed team contexts

Main skills

What the interview asks about

1. 1.C# and .NET service design

   Building robust backend services requires mastery of .NET patterns, async programming, and architectural decisions that affect scalability and maintainability.

   For example: “Payment processor must handle 1000 req/sec at sub-100ms latency. Describe ASP.NET Core architecture, dependency injection strategy, and async patterns.”

2. 2.MySQL optimization and data modeling

   Efficient database design and query performance directly impact system latency and cost at scale.

   For example: “Query runs 500ms, needs 50ms. Joins four tables on large dataset. Outline investigation, indexing strategy, and optimization approach.”

3. 3.API design and error handling

   Well-designed APIs prevent client bugs and reduce support burden; poor API design creates cascading failures downstream.

   For example: “You are versioning an API that currently has 200 production clients. A business requirement needs a new field in a frequently-called endpoint response. How would you handle versioning, and what would you consider about backward compatibility?”

4. 4.Production debugging and incident response

   Services fail in production; the ability to diagnose and fix issues quickly under pressure separates competent backend developers from strong ones.

   For example: “Customer bulk upload fails after 5 minutes, small files work fine, no logged exceptions. How would you diagnose, what monitoring enable?”

5. 5.Backend security and validation

   Backend services are targets for attack; secure coding practices prevent data breaches and injection vulnerabilities.

   For example: “You are building an endpoint that accepts user input for filtering database records. Walk me through your approach to preventing SQL injection, validating input, and ensuring the API cannot be abused to access unauthorized data.”

A task you may get

Design and implement a backend service in C# that handles a specific business requirement: define the API contract, database schema, error handling, and optimization strategy. Include unit tests and documentation.

How to prepare

• Review your past C# projects and prepare to discuss architectural decisions, performance optimizations, and scaling challenges you solved
• Study SOLID principles and design patterns in .NET; practice explaining how you would apply them to a new service
• Work through a complex MySQL query optimization scenario: write the slow query, identify the bottleneck, and test index and query rewrites
• Practice debugging simulated production issues: given logs and metrics, identify the root cause and propose a fix

The facts

Pay

$60–110/hr

Open to

Bangladesh, Hong Kong, India, Indonesia, Japan, Kazakhstan, Kyrgyzstan, Malaysia, Pakistan, Philippines, Singapore, Sri Lanka, Taiwan, Thailand, Uzbekistan, Vietnam, Austria, Belarus, Belgium, Denmark, France, Germany, Greece, Italy, Netherlands, Portugal, Russia, Spain, Switzerland, United Kingdom, Argentina, Brazil, Chile, Colombia, Mexico, Peru, Algeria, Bahrain, Egypt, Iraq, Jordan, Kuwait, Lebanon, Libya, Morocco, Oman, Palestine, Qatar, Saudi Arabia, Tunisia, United Arab Emirates, United States, Canada, Nigeria, Kenya, South Africa, Ghana, Ethiopia

Field

Software Engineering

Role type

Specialist

Posted

4/17/2026

Places left

2

We wrote this page from the public micro1 listing. It may be out of date, so read the full posting before you apply.