Principal Software Engineer

CoStar Group, Inc.; Irvine (CA); On-site; USD 214,000 - 297,000; Full time

Benefits offered by this job

Healthcare coverage

Mental health counseling

401K with match

Employee stock plan

Paid time off

Tuition reimbursement

On-site fitness

Job summary

CoStar Group in Irvine is seeking a Principal Software Engineer to own architecture across full-stack products and secure data pipelines. You will translate complex requirements into scalable designs and guide teams through architectural decisions and governance.

You will lead with communication through diagrams, mentor engineers, and ensure security, performance, and reliability across enterprise-scale systems.

Qualifications

• 10+ years in designing enterprise web applications (complex, high-volume).
• Deep knowledge of microservices, serverless, data and web apps.
• Experience designing secure systems and security-minded development practices.
• Experience with AWS services (Lambda, DynamoDB, API Gateway, etc.).
• Experience with relational and NoSQL databases and data modeling.
• Experience in event-driven architectures and real-time data streaming.
• Strong ability to communicate through architectural diagrams.

Responsibilities

• Collaborate with Product and Technology leadership to translate requirements into technical solutions.
• Define architectural direction based on project needs, resources, and timing.
• Document systems with diagrams and architecture docs for multiple systems.
• Mentor engineers on microservices, micro-frontends, and data streaming practices.
• Advocate for security, observability, performance, and reliability in all designs.

Skills

Microservices

Serverless

AWS

Architecture design

Security minded

Java

C#

Python

JavaScript/TypeScript

Data streaming

NoSQL

Relational DBs

GraphQL

TDD

Git

Azure DevOps

Terraform

Education

Bachelor's Degree

Tools

Git

Azure DevOps

Terraform

Job description

Principal Software Engineer

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 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.

Our CoStar development team is looking for an experienced Principal Software Engineer to own the architecture and design of our software systems, from full stack web products to high-volume, secure data pipelines. This role includes design of new greenfield systems, so being able to convert product requirements to system architecture is essential. It will also help guide the ongoing architectural evolution of our current solutions, meaning the ability to fully understand existing complex systems is required as well. It is a highly collaborative role that comes with great influence on the technical solutions we are building and requires strong communication and cooperation across multiple teams and disciplines. This includes developers within the same team and Software Architects throughout the company. To be successful in this role you must be a problem-solving, collaborative person with deep technical skills, and the ability to work in a secure, performant, enterprise-scale environment. This position will be located in Irvine and is in office Monday through Thursday and work from home on Friday.

Responsibilities

Work in partnership with Product and Technology leadership to deeply understand a project’s complex functional requirements and drive implementation of appropriate technical solutions. Collaborate with development teams to determine the right architectural direction based on project needs, level of effort, resourcing, timing, etc. Understand existing systems and ensure they are well documented, so that you become a go-to source of architectural information across multiple systems. Act as an architectural subject matter expert and source of good advice to technical leadership and developers. Drive and evangelize architectural principles and guidelines to ensure high quality, consistent results across teams. Partner with engineering managers to ensure that they are following established architectural best practices. Create, organize, and maintain architectural diagrams and other system documentation. Provide architectural guidance and mentoring to other technical staff on topics such as microservices, micro-frontends, high-volume data streaming / event processing, etc. Stay up to date with emerging technologies, evaluate and development practices and identify how they might improve existing or new systems we are building. Develop a deep understanding of the CoStar business, and how the technical work we are doing aligns with that strategy. Advocate for and design solutions that are well‑instrumented, so that we are confident we are building stable, high-performance products. Be a go-to resource in the understanding and diagnosis of complex performance, scalability, and reliability issues. Be an advocate for security and ensure that we are architecting and building secure software products and platforms.

Basic Qualifications

• Bachelor’s Degree required from an accredited, not-for-profit, in-person college/university
• A track record of commitment to prior employers
• 10+ years of hands‑on experience in designing highly complex enterprise‑level web applications, including deep knowledge of microservices, serverless, data, and web applications.
• Experience designing and buildings secure systems and security minded development practices.
• Experience with financial data is a big plus.
• Extensive experience in software engineering with expert-level proficiency in at least one of these programming languages: C#, Java, Python, JavaScript/TypeScript.
• Exposure to languages and platforms across the full web application stack is a big plus (e.g., GraphQL).
• Significant, hands‑on experience designing and implementing solutions using Amazon Web Services (AWS) services including Lambda, DynamoDB, CloudWatch, CloudFormation, SNS/SQS, S3, API Gateway, etc.
• Experience with Test Driven Development methodologies.
• Experience modeling and implementing large-scale relational and NoSQL database systems.
• Experience designing/implementing event‑oriented architectures and real‑time data streaming solutions.
• Strong ability to communicate through architectural diagrams.

Preferred Qualifications

• Architect‑level certifications from AWS, Azure or GCP
• Experience with agile development methodologies.
• Experience with modern source control and CI/CD technologies including Git or Azure DevOps.
• Experience establishing software development best practices, including standard, code reviews, source control, builds, testing and operations.
• Experience with Infrastructure as Code in Terraform.
• Experience in observability logging/tracing with CloudWatch and/or Kibana.
• Experience building highly secure software, including tokenization, OpenID, etc.
• Team or project leadership experience is a plus.

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.

• 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 snack

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: $214,000 - $297,000 (Hourly/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.

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. 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 37 years, giving us the perspective to create truly unique and valuable products and services. We’ve continually refined, transformed and perfected our approach to our business, creating a language that has become standard in our industry and for our customers. 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. 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 www.costargroup.com/careers as a result of your disability. You can request reasonable accommodations by sending an email to [e-mail].