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Senior .NET / SQL Performance Engineer

Recruitment.aiSan Jose, CA🇺🇸United StatesPosted 9 Sept 2026

Why This Role Stands Out

You'll make a significant impact by optimizing critical application performance and reducing database costs in this hybrid role. This position is ideal for a seasoned .NET and SQL expert who thrives on complex problem-solving and driving efficiency, offering excellent opportunities for skill development. Apply now to join a forward-thinking team and elevate your career!

Quick Overview

Seniority
Mid Senior
Work mode
Hybrid
Location
San Jose, CA, United States
Posted
Yesterday

Job Description

Senior .

Role Overview

We are seeking a Senior C#/.NET Engineer with deep SQL Server and Entity Framework performance expertise to identify and eliminate database performance bottlenecks within an Entity Framework-heavy application.

The engineer will analyze AWS RDS for SQL Server performance, identify expensive queries, trace those queries back into the C# application, optimize SQL/database access, improve indexes, and reduce application timeouts and database costs.

Responsibilities

  • Assess AWS RDS / SQL Server performance metrics and identify major bottlenecks.
  • Identify high-impact/slow-running SQL queries.
  • Trace problematic queries back to C# / Entity Framework code.
  • Analyze and optimize inefficient Entity Framework-generated SQL.
  • Where appropriate, convert inefficient Entity Framework/database access patterns into optimized SQL.
  • Optimize queries, stored procedures, database access patterns, and execution performance.
  • Review and optimize SQL Server indexes.
  • Troubleshoot application timeouts and database performance issues.
  • Build, test, and deploy C#/.NET and database performance improvements.
  • Review and remove/test SQL Server compatibility mode where appropriate.
  • Improve application performance while reducing AWS RDS/database hosting costs.
  • Share SQL/AWS performance knowledge with the development team.

Required Skills

  • 4–6+ years of strong C# / .NET Framework development experience.
  • Deep hands-on experience with Microsoft SQL Server.
  • Strong Entity Framework / ORM experience.
  • Demonstrated experience diagnosing database performance bottlenecks in .NET applications.
  • Strong SQL query writing and query optimization/tuning experience.
  • Ability to identify inefficient Entity Framework queries and optimize/rewrite the database interaction.
  • Strong knowledge of indexes, execution plans, query performance, locking/blocking, and timeouts.
  • Hands-on experience with AWS RDS for SQL Server.
  • Strong troubleshooting and root-cause analysis skills.

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