Principal Engineer, GenAI Innovation

Company: T-Mobile USA, Inc.
Location: Bellevue
Posted on: May 1, 2025

Job Description:

At T-Mobile, we invest in YOU! Our Total Rewards Package ensures that employees get the same big love we give our customers. All team members receive a competitive base salary and compensation package - this is Total Rewards. Employees enjoy multiple wealth-building opportunities through our annual stock grant, employee stock purchase plan, 401(k), and access to free, year-round money coaches. That's how we're UNSTOPPABLE for our employees!

Job Overview
The full stack Principal Engineer will work with a team of other software engineers to design, implement, and deploy complete systems which meet customer's requirements and are cloud native. The Principal Engineer will focus on creation of full stack software solutions that typically include front end web frameworks, back end services, micro services, databases, and all associated cloud infrastructure required to deploy and maintain the solution. Responsible for creating, deploying and supporting a full software solution. Expected to be an accomplished generalist across the full software stack.

Job Description

This position is to lead the architecting and development of custom GPT Actions, and Connectors for Enterprise GPT program. Currently we have 50 Actions/Connectors in roadmap to develop in order to deliver high impact GPT solutions, to build value for business.

Job Responsibilities:

• Designs and builds full stack web solutions including both the back end and front end
• Code Review and mentoring of other team members
• Designs / crafts sophisticated scheduled jobs and micro-services defining new patterns and orchestrations
• Designs / implements detailed data storage mechanisms using relational and non-relational data stores
• Explores, creates and configures cloud services using infrastructure as code. Recommends new cloud services and patterns
• Presents new ideas which improve an existing system/process/service. Presents new ideas which apply new frameworks to improve an existing system/process/service
• Collaborates with team to break down features into user stories and estimate them
• Awareness of technology roadmap. Updates job knowledge by monitoring and understanding emerging engineering practices. Continuously learns, builds content, and mentors others in specific subject areas.
• Informally coaches and builds into the development of others through mentoring or in-house workshops and learning sessions. Mentors and develops engineers across functional teams on technology decisions.
• Influences technology and policy decisions made at Director+ level across the organization. Understands financial decisions, including NPV and return on investment, based on customer experience/business drivers.
• Develops and integrates Generative AI solutions into full stack applications, using LLMs, APIs, and AI-driven workflows to enhance user experience and automation.
  
  Education:
  
  
  • Bachelor's Degree in Computer Science or Engineering (Required)
    
    Work Experience:
    
    7+ years of proven experience in:
    
    • Full stack web development experience, including front end and back end
    • Technical engineering experience
    • Crafting database schemas, writing SQL (Required)
    • 3+ years of DevOps experience with infrastructure as code (Required)
    • 4-7 years using cloud services from AWS, Azure, or GCP (Required)
    • 2+ years of experience working with Generative AI models, APIs (such as OpenAI, Hugging Face, or similar), and AI/ML integration in software development (Preferred)
    • Experience coaching and mentoring team members (Preferred)
      
      Knowledge, Skills, and Abilities:
      
      
      • Expected to be able to set up a completely new full stack environment from scratch, including build steps and backend infrastructure (Required)
      • Knowledge of HTML, CSS, Webpack, JavaScript, at least one front-end framework, and one back-end framework (Required)
      • Understands web protocols, how full stack applications operate, and data flows (Required)
      • Understanding of database modeling and SQL. Capable of performance tuning and refactoring from one data store to another (Required)
      • Deep understanding of cloud system parameters, configurations, and how to alter them for desired results (Required)
      • Experience integrating AI-driven components, such as chatbots, automated content generation, or recommendation systems, into full stack applications (Preferred)
      • Good understanding of adjacent processes and workflows (Required)
        
        --- At least 18 years of age
        --- Legally authorized to work in the United States
        
        Travel:
        Travel Required (Yes/No):Yes
        
        DOT Regulated:
        DOT Regulated Position (Yes/No):No
        Safety Sensitive Position (Yes/No):No
        
        Base Pay Range: $129,400 - $233,400
        
        Corporate Bonus Target: 20%
        
        The pay range above is the general base pay range for a successful candidate in the role. The successful candidate's actual pay will be based on various factors, such as work location, qualifications, and experience, so the actual starting pay will vary within this range.
        
        At T-Mobile, employees in regular, non-temporary roles are eligible for an annual bonus or periodic sales incentive or bonus, based on their role. Most Corporate employees are eligible for a year-end bonus based on company and/or individual performance and which is set at a percentage of the employee's eligible earnings in the prior year. Certain positions in Customer Care are eligible for monthly bonuses based on individual and/or team performance. To find the pay range for this role based on hiring location, click here .
        
        At T-Mobile, our benefits exemplify the spirit of One Team, Together! A big part of how we care for one another is working to ensure our benefits evolve to meet the needs of our team members. Full and part-time employees have access to the same benefits when eligible. We cover all of the bases, offering medical, dental and vision insurance, a flexible spending account, 401(k), employee stock grants, employee stock purchase plan, paid time off and up to 12 paid holidays - which total about 4 weeks for new full-time employees and about 2.5 weeks for new part-time employees annually - paid parental and family leave, family building benefits, back-up care, enhanced family support, childcare subsidy, tuition assistance, college coaching, short- and long-term disability, voluntary AD&D coverage, voluntary accident coverage, voluntary life insurance, voluntary disability insurance, and voluntary long-term care insurance. We don't stop there - eligible employees can also receive mobile service & home internet discounts, pet insurance, and access to commuter and transit programs! To learn about T-Mobile's amazing benefits, check out www.t-mobilebenefits.com .
        
        Never stop growing!
        As part of the T-Mobile team, you know the Un-carrier doesn't have a corporate ladder-it's more like a jungle gym of possibilities! We love helping our employees grow in their careers, because it's that shared drive to aim high that drives our business and our culture forward. By applying for this career opportunity, you're living our values while investing in your career growth-and we applaud it. You're unstoppable!
        
        T-Mobile USA, Inc. is an Equal Opportunity Employer. All decisions concerning the employment relationship will be made without regard to age, race, ethnicity, color, religion, creed, sex, sexual orientation, gender identity or expression, national origin, religious affiliation, marital status, citizenship status, veteran status, the presence of any physical or mental disability, or any other status or characteristic protected by federal, state, or local law. Discrimination, retaliation or harassment based upon any of these factors is wholly inconsistent with how we do business and will not be tolerated.
        
        Talent comes in all forms at the Un-carrier. If you are an individual with a disability and need reasonable accommodation at any point in the application or interview process, please let us know by emailing ApplicantAccommodation@t-mobile.com or calling 1-844-873-9500 . Please note, this contact channel is not a means to apply for or inquire about a position and we are unable to respond to non-accommodation related requests.

Keywords: T-Mobile USA, Inc., Bellevue , Principal Engineer, GenAI Innovation, Education / Teaching , Bellevue, Washington