Principal Software Engineer – .NET, AWS & AI

Thomson Reuters Corp.; Washington (District of Columbia); Hybrid; USD 183,000 - 340,000; Full time

Benefits offered by this job

Hybrid Work Model

Mental Health Days off

Tuition Reimbursement

401k with company match

Job summary

Thomson Reuters Corp. is seeking a hands-on Principal Software Engineer to lead architecture and delivery for large-scale production systems using C#/.NET Core and AWS.

The role emphasizes cloud-native modernization, microservices, and secure, scalable APIs, with a focus on responsibly integrating AI/ML capabilities into our tax compliance platforms. The ideal candidate has 10+ years of professional software engineering, hands-on leadership at the principal level, and deep AWS experience.

Qualifications

• 10+ years of professional software engineering experience with demonstrated Principal Engineer or equivalent senior IC scope.
• Strong, recent, hands-on C#/.NET Core engineering experience, including personally designing and implementing production software.
• Deep, hands-on production experience with AWS services and cloud-native architectures.
• Proven experience architecting and implementing large-scale distributed systems, microservices, APIs, and highly available applications.
• Experience modernizing complex legacy applications into scalable cloud-native solutions.
• Principal-level architecture and system design ownership across multiple teams.
• Ability to remain hands-on with engineering delivery while providing technical leadership.
• Experience with AI/ML, Generative AI, LLMs, or RAG in production is highly preferred.

Responsibilities

• Own architecture and system design for large-scale production platforms, making decisions on scalability, reliability, performance, and security.
• Design and build production software using C#/.NET Core and AWS, actively contributing to implementation and reviews.
• Lead modernization of legacy applications into cloud-native architectures and microservices ecosystems.
• Provide hands-on technical leadership through architecture reviews, mentoring, and engineering best practices.
• Identify opportunities to incorporate AI/ML capabilities into production products and roadmaps.

Skills

C#/.NET Core

AWS

Distributed systems

AI/ML

Principal-level leadership

Education

Bachelor's degree in Computer Science or related

Tools

EC2

S3

Elastic Load Balancing

Auto Scaling

RDS

Lambda

SQS

Kubernetes

Job description

**About the Role****hands-on Principal Software Engineer with deep, recent C#/.NET Core and AWS experience building large-scale distributed systems and cloud-native platforms**, along with experience applying **AI/ML, Generative AI, large language models (LLMs), retrieval-augmented generation (RAG), or agentic AI capabilities in production environments.**This is a **Principal-level individual contributor role** requiring demonstrated ownership of **architecture and technical direction for complex, enterprise-scale production systems**. The successful candidate will have operated at **Principal Engineer or equivalent scope**, influencing multiple engineering teams while **remaining actively hands-on with architecture, design, development, and implementation.**You will play a key role in the modernization and evolution of our U.S. tax compliance solutions, helping establish technical direction, improve platform scalability and reliability, and responsibly incorporate AI-enabled capabilities into our products.Candidates outside the Washington, DC area must be willing and able to travel to the Washington, DC office as needed.* **Own architecture and system design for complex, large-scale production platforms**, making technical decisions around scalability, reliability, performance, security, and maintainability.* **Design and build production software using C#/.NET Core and AWS**, remaining actively involved in implementation, technical problem-solving, design reviews, and engineering delivery.* **Lead the modernization of complex legacy applications into cloud-native architectures**, including distributed systems, microservices, APIs, data services, and containerized workloads.* **Establish technical direction and influence architecture and engineering decisions across multiple teams.*** Provide hands-on technical leadership through architecture and design reviews, code guidance, troubleshooting, mentoring, and engineering best practices.* Identify and help implement opportunities to incorporate **AI/ML and Generative AI capabilities into production products.*** Contribute to the long-term technical roadmap and communicate architecture decisions, trade-offs, risks, and recommendations.**About You**You're a fit for this Principal Software Engineer role if you bring:* 10+ years of professional software engineering experience with demonstrated **Principal Engineer or equivalent senior individual contributor scope.*** **Strong, recent, hands-on C#/.NET Core engineering experience, including personally designing and implementing production software.*** **Deep, hands-on production experience with Amazon Web Services (AWS)**, designing and implementing cloud-native systems using multiple AWS services such as **EC2, S3, Elastic Load Balancing, Auto Scaling, RDS, Lambda, SQS, and container services.*** **Proven experience architecting AND implementing large-scale distributed systems, microservices, APIs, and highly available production applications.*** **Demonstrated experience modernizing complex legacy applications into scalable, resilient cloud-native solutions.*** **Principal-level architecture and system design ownership**, including making significant technical trade-offs, setting technical direction, and influencing engineering decisions across multiple teams.* **Proven ability to remain hands-on with engineering delivery while providing Principal-level technical leadership.*** Strong knowledge of software architecture, object-oriented design, data structures, algorithms, design patterns, API design, relational databases, and modern engineering practices.* Strong communication and collaboration skills with the ability to influence across Product, Engineering, Security, Quality Assurance, Data, and Operations.* Bachelor's degree in Computer Science or a related technical discipline, or equivalent practical experience.* **Experience designing, building, or integrating production AI/ML, Generative AI, LLM, RAG, or agentic AI capabilities is highly preferred.*** Experience with containers, Kubernetes, API gateways, infrastructure automation, Python, TypeScript, Node.js, React, or Angular is preferred.**#LI-TH1*** **Hybrid Work Model:** We've adopted a flexible hybrid working environment for our office-based roles while delivering a seamless experience that is digitally and physically connected.* **Flexibility & Work-Life Balance:** Flex My Way is a set of supportive workplace policies designed to help manage personal and professional responsibilities, whether caring for family, giving back to the community, or finding time to refresh and reset. This builds upon our flexible work arrangements, including work from anywhere for up to 8 weeks per year, empowering employees to achieve a better work-life balance.* **Career Development and Growth:** By fostering a culture of continuous learning and skill development, we prepare our talent to tackle tomorrow's challenges and deliver real-world solutions. Our Grow My Way programming and skills-first approach ensures you have the tools and knowledge to grow, lead, and thrive in an AI-enabled future.* **Industry Competitive Benefits:** We offer comprehensive benefit plans to include flexible vacation, two company-wide Mental Health Days off, access to the Headspace app, retirement savings, tuition reimbursement, employee incentive programs, and resources for mental, physical, and financial wellbeing.* **Culture:** Globally recognized, award-winning reputation for inclusion and belonging, flexibility, work-life balance, and more. We live by our values: Obsess over our Customers, Compete to Win, Challenge (Y)our Thinking, Act Fast / Learn Fast, and Stronger Together.* **Social Impact:** Make an impact in your community with our Social Impact Institute. We offer employees two paid volunteer days off annually and opportunities to get involved with pro-bono consulting projects and Environmental, Social, and Governance (ESG) initiatives.* **Making a Real-World Impact:** We are one of the few companies globally that helps its customers pursue justice, truth, and transparency. Together, with the professionals and institutions we serve, we help uphold the rule of law, turn the wheels of commerce, catch bad actors, report the facts, and provide trusted, unbiased information to people all over the world.In the United States, Thomson Reuters offers a comprehensive benefits package to our employees. Our benefit package includes market competitive health, dental, vision, disability, and life insurance programs, as well as a competitive 401k plan with company match. In addition, Thomson Reuters offers market leading work life benefits with competitive vacation, sick and safe paid time off, paid holidays (including two company mental health days off), parental leave, sabbatical leave. These benefits meet or exceeds the requirements of paid time off in accordance with any applicable state or municipal laws. Finally, Thomson Reuters offers the following additional benefits: optional hospital, accident and sickness insurance paid 100% by the employee; optional life and AD&D insurance paid 100% by the employee; Flexible Spending and Health Savings Accounts; fitness reimbursement; access to Employee Assistance Program; Group Legal Identity Theft Protection benefit paid 100% by employee; access to 529 Plan; commuter benefits; Adoption & Surrogacy Assistance; Tuition Reimbursement; and access to Employee Stock Purchase Plan.Thomson Reuters complies with local laws that require upfront disclosure of the expected pay range for a position. The base compensation range varies across locations.Eligible office location(s) for this role include one or more of the following: New York City, San Francisco, Los Angeles, and/or Irvine, CA; McLean, VA; Washington, DC. The base compensation range for the role in any of those locations is $183,100 USD - $340,000 USD.Base pay is positioned within the range