Principal Engineer, Software Fullstack

Principal Software Engineer, Full Stack Ingestion (L07)

About T-Mobile
T-Mobile US, Inc. (NASDAQ: TMUS), headquartered in Bellevue, Washington, is Americas supercharged Un-carrier, connecting millions through its strong nationwide network and flagship brands, T-Mobile and Metro by T-Mobile. Customers benefit from an unmatched combination of value, quality, and exceptional service experience.
About TMUS Global Solutions
TMUS Global Solutions is a world-class technology powerhouse accelerating the companys global digital transformation. With a culture built on growth, inclusivity, and global collaboration, the teams here drive innovation at scale, powered by bold thinking.

About the Role

Principal Engineer, Software Full Stack is responsible for designing, implementing, and delivering comprehensive full stack software solutions that operate in cloud environments and meet complex customer and business requirements. This role spans front-end and back-end systems, microservices, streaming solutions, databases, and cloud infrastructure, with ownership across the full software lifecycle. The Principal Engineer provides deep technical expertise, supports and maintains deployed solutions, and sets technical direction through hands-on design and implementation. Success is measured by the creation, deployment, and long-term support of scalable, reliable, and maintainable cloud-native software systems. This role impacts the organization by enabling robust software platforms that support customer objectives and operational efficiency.

What Youll Do

• Design full stack web solutions that deliver complete, end-to-end software systems meeting customer requirements
• Implement and deploy front-end, back-end, microservices, streaming, database, and cloud infrastructure components
• Review code and mentor engineers to improve software quality, maintainability, and team capabilities
• Develop advanced scheduled jobs and microservices to support new architectural patterns and orchestrations
• Design and implement relational and non-relational data storage solutions to meet application needs
• Configure and manage cloud services using infrastructure-as-code practices to deploy and maintain software solutions
• Present and apply new ideas, frameworks, and patterns to enhance existing systems, processes, and services
• Support and maintain production systems to ensure reliability, scalability, and performance

What Youll Bring

• Bachelors Degree in Computer Science, Engineering, or a related field, or equivalent practical experience
• 1012 years of hands-on experience building and supporting full stack software applications
• Deep experience designing and implementing systems across front-end, back-end, and cloud layers
• Proven ability to mentor and coach engineers to elevate technical quality and team effectiveness
• Strong problem-solving skills with the ability to reason across complex systems and workflows
• Strong communication skills to collaborate effectively with technical and non-technical stakeholders

Must Have Skills

• Expert-level experience building full stack applications end to end, from front-end to backend infrastructure
• Ability to set up a complete full stack environment from scratch, including build steps and backend infrastructure
• Proficiency with front-end technologies including HTML, CSS, JavaScript, Webpack, and at least one modern front-end framework
• Proficiency with backend frameworks and RESTful web services
• Strong SQL skills, including database modeling, schema design, performance tuning, and data store refactoring
• Deep understanding of web protocols, full stack application behavior, and data flows
• Advanced experience with cloud platforms such as Azure, AWS, or GCP
• Strong understanding of cloud system configurations, parameters, and optimization techniques
• Experience using infrastructure-as-code to configure, deploy, and maintain cloud services
• Proficiency with modern programming languages such as Python and Java

Nice to Have

• Experience with streaming and distributed data technologies such as Spark and Kafka
• Experience with build and test tooling such as Maven, JUnit, and Webpack
• Experience introducing and evolving architectural patterns in complex systems
• Broad understanding of adjacent engineering processes and workflows across teams