Senior Software Engineer (C#/.NET)
CoStar Group1 day ago
Arlington, VA, USASenior
Base Salary
$143k - $187k/yr
Responsibilities
- Build large-scale distributed, API-driven systems and web applications for tens of thousands of users.
- Design and implement AI-powered solutions, including AI skills, agents, tools, intelligent workflows, and customer-facing applications.
- Develop robust, efficient, and maintainable software using C#, .NET Framework, SQL Server, and AWS.
- Improve monitoring, telemetry, observability, replayability, diagnostics, and system reliability through AI and automated solutions.
- Create automation that streamlines research workflows, improves information discovery, and increases operational efficiency.
- Lead software design, development standards, and code reviews.
- Collaborate with Product, Research, and Data teams to identify AI-driven business opportunities.
- Evaluate emerging technologies, trends, and best practices for the technology platform and development practices.
Requirements
- Bachelor’s degree from an accredited, not-for-profit, in-person university or college.
- 5+ years of deep C#/.NET development experience, including cross-platform communication technologies such as Web API.
- Experience with MSSQL or other relational database development.
- Working knowledge and experience with cloud platforms such as AWS or Azure.
- Experience with RESTful web services and ASP.NET MVC.
- Experience architecting, designing, and building large-scale distributed, service-oriented systems and web applications in an agile environment.
- Experience with data modeling, including conceptual, logical, and physical designs.
- Familiarity with large language models, prompt engineering, or agent-based architectures.
- Experience with monitoring, telemetry, observability, or automated diagnostics platforms.
- Strong understanding of data quality principles, data governance concepts, and data-centric application design.
- Strong communication skills with business and technical partners.
- Preferred experience with AWS Lambda, DynamoDB, SQS, AI agents, workflow automation platforms, intelligent search solutions, and AI-assisted software development practices.
- A track record of commitment to prior employers.
Benefits
- Arlington, VA position with in-office work Monday through Thursday and work from home on Friday.
- Comprehensive medical, vision, dental, and prescription drug coverage.
- Life, legal, and supplementary insurance.
- Virtual and in-person mental health counseling for individuals and families.
- Commuter and parking benefits.
- 401(k) retirement plan with matching contributions.
- Employee stock purchase plan and paid time off.
- Tuition reimbursement and internal training.
- On-site fitness center or reimbursed fitness center membership costs where available.
- Employee Resource Groups, complimentary beverages, fresh fruit, and healthy snacks.
Categories
About CoStar Group
CoStar Group builds subscription databases, analytics, and online marketplaces for commercial and residential real estate professionals, investors, and advertisers. Its portfolio includes CoStar (research and data), LoopNet (commercial listings), and Apartments.com (rental listings), generating revenue from subscriptions, listings, and advertising. The company is publicly traded on NASDAQ (CSGP) and is headquartered in Arlington, Virginia, with inclusion in the S&P 500 index.