Lead Software Engineer- CoStar- Arlington, VA

Lead Software Engineer – Arlington, VA

CoStar Group is a leading global provider of commercial and residential real estate information, analytics, and online marketplaces. We are on a mission to digitize the world’s real estate, empowering people to discover properties, insights, and connections that improve their businesses and lives.

As CoStar’s next Lead Software Engineer, you will lead the build of a greenfield, enterprise‑scale web application infused with AI, leveraging modern technologies and frontier models. You will drive the development of AI‑powered product experiences while shaping AI‑first engineering workflows that redefine how software is built. This is a high‑impact role to architect, innovate, and influence the future of intelligent applications at scale.

• Architect scalable, resilient distributed systems – defining service boundaries, data contracts, and cross‑team API standards for an enterprise‑scale platform.
• Build responsive, high‑performance applications using React, Node.js, Tailwind, etc.
• Work with cloud‑native services (Azure/AWS/GCP), containers, and microservices.
• Optimize for performance, observability, and developer productivity.
• Leverage AI tooling & automation (CI/CD, code generation, test generation).
• Influence and establish AI‑first engineering practice (vibe coding, human‑in‑the‑loop, debugging).
• Establish AI culture & mentorship (team upskilling, lifecycle redefinition).
• Continually evaluate emerging technologies to identify opportunities, trends, and best practices that can be used to strengthen CoStar’s technology platform and development practices.
• Develop and maintain an in‑depth working knowledge of the CRE industry and CoStar’s business model/technology.

• Bachelor’s degree required from an accredited, non‑profit, in‑person university or college.
• 8+ years of production development experience in modern technologies, such as React, Vue, Type Script, Node.js, C#, .NET, Open Search, Kafka, SQL, No
  
  SQL.
• Demonstrable track record of building and launching successful products and platforms.
• Experience designing for high availability, horizontal scalability, and production observability at enterprise scale.
• Experience with cloud technologies such as AWS, Cloud‑managed services, etc.
• Experience in Agile/Scrum processes and continuous delivery practices.
• Experienced in unit, performance, and automation testing.
• Deep understanding of the business requirements for the software you build.
• Active role in mentoring developers and building consensus.

• Experience managing a large enterprise‑level code base, code quality, and dependencies.
• Experience with C#, Node.js, and/or React.
• Experience building agents and workflows using modern AI patterns.
• Leverage Vibe coding to improve productivity and quality.
• Excellent written and verbal communication skills.
• Commercial Real Estate (CRE) knowledge is a bonus.

• Generous compensation and performance‑based incentives.
• Comprehensive healthcare coverage (Medical, Vision, Dental, Prescription Drug, Life, legal, and supplementary insurance).
• Virtual and in‑person mental health counseling services.
• 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 (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 healthy snacks.

CoStar Group is an Equal Employment Opportunity Employer; we maintain a drug‑free workplace and perform pre‑employment substance abuse testing. CoStar Group (NASDAQ: CSGP) is a leading global provider of commercial and residential real estate information, analytics, and online marketplaces. We are committed to creating a diverse environment and are proud to be an 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 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. Reasonable accommodations may be requested by calling 1‑855‑840‑1715 or contacting