# Senior Software Engineer - LoopNet at CoStar Group

- Company: CoStar Group
- Company website: https://www.costargroup.com
- Type: Startups
- Level: Senior
- Location: Irvine (US)
- Work setup: On-site
- Pay: $124K to $187K base salary per year (USD)
- Posted: 2026-09-23
- Apply by: 2026-11-07
- Apply: https://costar.wd1.myworkdayjobs.com/en-US/CoStarCareers/job/Irvine-US/Senior-Software-Engineer---LoopNet_R39829
- Page: https://www.1752.vc/careers/jobs/costar-group-senior-software-engineer-loopnet/

## About the role

We are seeking a highly skilled Senior Software Engineer with deep expertise in C#/.NET, AWS cloud development, and hands-on experience with AI coding tools such as Claude Code or GitHub Copilot. In this role, you will contribute to building scalable, high-quality systems across multiple products and brands—including LoopNet.com—while leveraging modern AI-driven development practices to accelerate delivery and improve code quality.

## What they're looking for

- Bachelor’s degree from an accredited, not-for-profit university or college
- A demonstrated track record of commitment with prior employers
- 6+ years of production development experience with C# and .NET or .NET Core
- Proven history of building and launching successful products and platforms
- Experience delivering products that meet specifications and performance SLAs
- Solid experience writing unit, performance, and automated end-to-end tests