LoopNet - Senior Software Engineer (C#/.NET)

LoopNet - Senior Software Engineer (C#/.NET) Job Description CoStar Group (NASDAQ: CSGP) is a leading global provider of commercial and residential real estate information, analytics, and online marketplaces. Included in the S&P 500 Index, CoStar Group is on a mission to digitize the world’s real estate, empowering all people to discover properties, insights and connections that improve their businesses and lives. We have been living and breathing the world of real estate information and online marketplaces for over 35 years, giving us the perspective to create truly unique and valuable offerings for our customers. We’ve continually refined, transformed and perfected our approach to our business, creating a language that has become standard in our industry, for our customers, and even our competitors. We continue that effort today and are always working to improve and drive innovation. LoopNet, the most popular place to find a space, is the #1 global commercial real estate marketplace. With more than 12 million global unique monthly visitors, LoopNet provides brokers, buyers and sellers with what they need to meet and make deals. LoopNet has established itself as the most effective and far-reaching digital marketplace for commercial real estate owners and brokers. This position is in Irvine, CA and offers 4 days a week on-site with 1 day working from home. RESPONSIBILITIES Design and develop enterprise applications using software design principles/patterns to attain high reusability and maintainability. Deep knowledge and experience in writing unit testable software with C#. Develop an in-depth understanding of CoStar’s product architecture and frameworks. Maintain and contribute to CoStar’s product platform as necessary. Develop database stored procedures and SQL scripts that meet CoStar database standards to implement product requirements. Participate and drive continuous improvement within CoStar’s Agile/Scrum teams. Build consensus among different teams working on software development projects. Facilitate discussions among peer .NET and database developers to exchange new ideas and improvements. Continually evaluate emerging technologies to identify opportunities, trends and best practices that can be used to strengthen CoStar’s technology platform and development practices. REQUIRED QUALIFICATIONS Bachelor’s degree required from an accredited, not-for-profit university or college. A track record of commitment to prior employers. 7+ years of production development experience with .NET or .NET Core. Working experience with AWS cloud technologies (file storage, data storage, search, cache), Apache Kafka. Frontend working knowledge (Vue, React or Angular, and TypeScript). A demonstrable track record of building and launching enterprise products/platforms. Deliver products that meet specifications and performance SLA; experience in unit, performance, and integration tests. Experience with Git-based workflows. Deeply understand enterprise application business logic. PREFERRED QUALIFICATIONS Experience in relational database design (MS SQL or MySQL) including performance optimization and NoSQL design. Application security knowledge. Leverage AI Coding Tools for development, refactoring, and debugging (Claude Code, GitHub Copilot or equivalent). WHAT’S IN IT FOR YOU When you join CoStar Group, you’ll experience a collaborative and innovative culture working alongside the best and brightest to empower our people and customers to succeed. We offer you generous compensation and performance-based incentives. CoStar Group also invests in your professional and academic growth with internal training, and tuition reimbursement. Our benefits package includes (but is not limited to): Comprehensive healthcare coverage: Medical / Vision / Dental / Prescription Drug. Life, legal, and supplementary insurance. Virtual and in person mental health counseling services for individuals and family. Commuter and parking benefits. 401(K) retirement plan with matching contributions. Employee stock purchase plan. Paid time off. Tuition reimbursement. On-site fitness center and/or reimbursed fitness center membership costs (location dependent), with yoga studio, Peloton, personal training, group exercise classes. Access to CoStar Group’s Employee Resource Groups. Complimentary gourmet coffee, tea, hot chocolate, fresh fruit, and other healthy snacks. We welcome all qualified candidates who are currently eligible to work full-time in the United States to apply. However, please note that CoStar Group is not able to provide visa sponsorship for this position. This position offers a base salary range of $124,000-$187,000, based on relevant skills and experience and includes a generous benefits plan. CoStar Group is an Equal Employment Opportunity Employer; we maintain a drug-free workplace and perform pre-employment substance abuse testing. CoStar Group is committed to creating a diverse environment and is proud to be an equal opportunity workplace and affirmative action employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status. CoStar Group is also committed to compliance with all fair employment practices regarding citizenship and immigration status. If you are a qualified individual with a disability or a disabled veteran, you may request a reasonable accommodation if you are unable or limited in your ability to use or access as a result of your disability. You can request reasonable accommodations by sending an email to View email address on click.appcast.io. #J-18808-Ljbffr