Lead Software Engineer- CoStar Suite- Arlington, VA

CoStar Group•Arlington, VA

3d•$145,000 - $222,000•Hybrid

About The Position

As CoStar’s Lead Software Engineer, you will lead development of a greenfield, enterprise-scale web application infused with AI, using modern technologies and frontier models. You will drive AI-powered product experiences and help shape AI-first engineering workflows. The role involves architecting and innovating intelligent applications at scale. The position is based in Arlington, Virginia. It is onsite Monday through Thursday, with the option to work from home on Friday. The successful candidate will develop and maintain an in-depth working knowledge of the commercial real estate industry and CoStar’s business model and technology.

Requirements

Bachelor’s degree from an accredited, not-for-profit, in-person university or college.
A track record of commitment to prior employers.
At least 8 years of production development experience with modern technologies such as React, Vue, TypeScript, Node.js, C#, .NET, OpenSearch, Kafka, SQL, or NoSQL.
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 and cloud-managed services.
Experience with Agile/Scrum processes and continuous delivery practices.
Experience in unit, performance, and automation testing.
Deep understanding of the business for which software is being built.
Ability to actively mentor developers and build consensus.
Excellent written and verbal communication skills.

Nice To Haves

Experience managing a large enterprise-level codebase, code quality, and dependencies.
Experience with C#, Node.js, and/or React.
Experience building agents and workflows using modern AI patterns.
Experience leveraging vibe coding to improve productivity and quality.
Commercial real estate knowledge.

Responsibilities

Architect scalable, resilient distributed systems, including defining service boundaries, data contracts, and cross-team API standards for an enterprise-scale platform.
Build responsive, high-performance applications using technologies such as React, Node.js, and Tailwind.
Work with cloud-native services, containers, and microservices.
Optimize for performance, observability, and developer productivity.
Leverage AI tooling and automation, including CI/CD, code generation, and test generation.
Influence and establish AI-first engineering practices, including vibe coding, human-in-the-loop approaches, and debugging.
Establish an AI culture through team upskilling and redefinition of the development lifecycle.
Evaluate emerging technologies to identify opportunities, trends, and best practices that strengthen CoStar’s technology platform and development practices.
Develop and maintain an in-depth working knowledge of the commercial real estate industry and CoStar’s business model and technology.
Mentor developers and build consensus.

Benefits

Generous compensation and performance-based incentives.
Professional and academic growth investment.
Medical, vision, dental, and prescription drug coverage.
Life, legal, and supplementary insurance.
Virtual and in-person mental health counseling services for individuals and families.
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, depending on location, with yoga studio, Pelotons, personal training, and group exercise classes.
Access to Employee Resource Groups.
Complimentary gourmet coffee, tea, hot chocolate, fresh fruit, and other healthy snacks.