Job Description
Overview
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 to 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. This is how we deliver for our customers, our employees, and investors. By equipping the brightest minds with the best resources available, we provide an invaluable edge in real estate.
As a Software Engineer on the Platform Development team, you will play a key role in expanding the data platform that supports all of CoStar Group’s largest brands including CoStar Suite, LoopNet, Homes.com and Apartments.com. You will deeply understand what drives the business for which you are building software. We firmly believe that what separates a good developer from a great one is a deep understanding of the business that they are supporting.
CoStar is investing heavily in artificial intelligence to accelerate software delivery, improve platform observability, automate research and business workflows, enhance product experiences through intelligent agents and skills, and improve data quality across enterprise systems. Successful candidates will demonstrate a willingness to learn, adopt, and apply AI technologies responsibly to solve complex business and engineering challenges.
This position is in Arlington, VA and is in office Monday through Thursday with work from home on Friday.
Responsibilities
- Build big, distributed, API-driven systems for tens of thousands of users.
- Design and implement AI-powered software solutions that enhance the customer experience, improve platform intelligence, and unlock new product capabilities across CoStar brands.
- Build and integrate AI skills, agents, tools, and intelligent workflows into internal systems and customer-facing applications.
- Produce bullet-proof code that is robust, efficient, and maintainable; our primary tools are C#, .NET Framework, SQL Server, AWS, Claude Code.
- Utilize AI models to enhance monitoring, replayability, observability, and diagnostic capabilities to improve system reliability, accelerate problem resolution, and reduce operational risk.
- Implement telemetry-driven solutions that proactively identify anomalies, performance bottlenecks, and potential customer-impacting issues.
- Learn software design, development standards, and take part in code reviews.
- Build intelligent automation solutions that streamline research workflows, improve information discovery, and increase operational efficiency across business functions.
- Continually evaluate emerging technologies to identify opportunities, trends, and best practices that can be leveraged to strengthen CoStar’s technology platform and development practices.
Basic Qualifications
- Bachelor’s Degree required from an accredited, not for profit, in person university or college.
- A track record of commitment to prior employers.
- 3+ years of deep .NET development (C#) development experience including cross platform communication technologies such as Web API.
- Working knowledge and experience with cloud-based platforms (AWS or Azure).
- Experience with RESTful web services.
- Experience in architecting, designing, and building distributed, service-oriented systems and web applications in an agile environment.
- Data modeling experience.
- Familiarity with large language models (LLMs), prompt engineering, or agent-based architectures.
- Experience working with monitoring, telemetry, observability, or automated diagnostics platforms.
- Strong understanding of data quality principles, data governance concepts, and data-centric application design.
Preferred Qualifications and Skills
- Strong communication skills (to both business and technical partners).
- SQL and database development knowledge.
- Familiarity with AWS PaaS services such as Lambda, DynamoDB, and SQS.
- Data modeling experience from conceptual, logical, and physical designs.
- Experience implementing AI agents, workflow automation platforms, or intelligent search solutions.
- Experience applying AI-assisted software development practices to improve engineering productivity and code quality.
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)
- Access to CoStar Group’s Employee Resource Groups
- Complimentary gourmet coffee, tea, hot chocolate, fresh fruit, and other healthy snacks
The final salary or hourly rate offered for this role will fall within the range set forth below based on a variety of factors, including but not limited to, geographic location, skills, and competencies.
Base Compensation: $108,000 - $154,000 Annually
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.
#LI-AR
CoStar Group is an Equal Employment Opportunity Employer; we maintain a drug-free workplace and perform pre-employment substance abuse testing
Skills Required
- Bachelor's degree from an accredited, not-for-profit, in-person university or college
- Track record of commitment to prior employers
- 3+ years of deep .NET and C# development experience, including Web API or similar cross-platform communication technologies
- Working knowledge and experience with cloud-based platforms such as AWS or Azure
- Experience with RESTful web services
- Experience architecting, designing, and building distributed, service-oriented systems and web applications in an agile environment
- Data modeling experience
- 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
- SQL and database development knowledge
- Familiarity with AWS PaaS services such as Lambda, DynamoDB, and SQS
- Data modeling experience across conceptual, logical, and physical designs
- Experience implementing AI agents, workflow automation platforms, or intelligent search solutions
- Experience applying AI-assisted software development practices to improve engineering productivity and code quality
CoStar Group Compensation & Benefits Highlights
The following summarizes recurring compensation and benefits themes identified from responses generated by popular LLMs to common candidate questions about CoStar Group and has not been reviewed or approved by CoStar Group.
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Healthcare Strength — Healthcare coverage is described as extensive, spanning medical, dental, vision, and prescription plans, with additional life and supplementary insurance options. Mental health counseling and wellness incentives are also part of the package, reinforcing the sense of strong health support.
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Wellbeing & Lifestyle Benefits — Lifestyle perks include commuter and gym reimbursements and daily lunch, alongside office snacks/drinks and company social events. Fitness stipends and wellness programs add to the perceived day-to-day value of the rewards package.
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Equity Value & Accessibility — Opportunities to become a shareholder via stock-related programs are highlighted as a meaningful element of total rewards. Equity and employee stock purchase options are positioned as an additional path to value beyond base pay.
CoStar Group Insights
What We Do
CoStar Group (NASDAQ: CSGP) is a global leader in commercial real estate information, analytics, online marketplaces, and 3D digital twin technology. Founded in 1986, CoStar Group is dedicated to digitizing the world’s real estate, empowering all people to discover properties, insights, and connections that improve their businesses and lives. CoStar Group’s major brands include CoStar, a leading global provider of commercial real estate data, analytics, and news; LoopNet, the most trafficked commercial real estate marketplace; Apartments.com, the leading platform for apartment rentals; Homes.com, the fastest-growing residential real estate marketplace; and Domain, one of Australia’s leading property marketplaces. CoStar Group’s industry-leading brands also include Matterport, a leading spatial data company whose platform turns buildings into data to make every space more valuable and accessible, STR, a global leader in hospitality data and benchmarking; Ten-X, an online platform for commercial real estate auctions and negotiated bids; and OnTheMarket, a leading residential property portal in the United Kingdom.
