Principal Engineer, Software

Job Description:

You Build it, you own it!!! Do you love building digital applications and leading development of digital applications? Do you want to join the fast-paced team who encourage innovation and expand both your leadership and development skills and experience? Join the next wave of innovation that is happening at T-Mobile. Work on projects that challenge your intellect, passion, drive and curiosity. We are looking for a Principal Engineer, Software to raise the bar for a high-performing team that delivers large scale solutions on PCF. If you are looking to work on projects that are top organizational priority for the company, provide compelling end-user experiences and improve customer satisfaction, look no further!

As a Principal Engineer, Software, you play a key technical leadership role in enabling T-Mobile's technology strategy for digital transformation by applying expertise in delivering high quality solutions tailored for maximum adoption. The successful candidate will build digital financing services and applications as well as drive continuous delivery and automation through adoption of a standard set of tools and automated processes.
The candidate must be
Customer and value focused; they win, so you win
Always forward thinking, driven by innovation
Refuses to accept the status quo and not afraid to take risk.
Self-directed; no need to push you to excel, it's just who you are
Relentless in solving customer pain points

You act as the technical and development lead on complex projects, contributing to strategic vision and technical decisions, participating in vendor analysis and selection projects, introducing process improvements, completing proof of concept projects for introduction of changes to our architecture, and providing oversight on the delivery work of other technical staff. You also serve as a key interface with other technical development and architecture teams, building new relationships through design and implementation of solutions. We embrace Agile methodology and full DevOps model, and expect you to take ownership of the solution you build and provide high caliber of production support.

Desired Characteristics.
Loves to code, digs code
Tech Geek
Forward thinking; future state of IT mindset; driven by innovation.
Refuses to accept the status quo and not afraid to take risk.
Hacker who assembles POCs rapidly and then standardizes to operationalize them
Proven success in building web hosted and/or cloudbased implementation and/or operations, and experience in building and deploying Enterprise wide Digital applications.
Strong verbal presentation and written communication skills.
Automation and Self-Service Mindset.


What you'll do in your role.
Write high-quality code and mentor others to do the same
Lead the development efforts for cloud-based applications and infrastructure by building frameworks/applications and working with developers to implement and operationalize them
Leverage open source technology such as Docker, Swarm, Mesos, Marathon Bash, Javascript, Python, Git, Jenkins, Linux, HAProxy, NGINX, AWS Cloud, ELK, Java, Kafka, MongoDB, Cassandra, Zookeeper, and plenty of others
Integrate systems using a wide variety of protocols like REST, SOAP, MQ, TCP/IP, JSON and others
Create development standards/guidelines for app teams, help them follow the DevOps model
Develop support documentation for acceptance of systems changes into production
Participate in code reviews and walkthroughs of technical specifications with other members of the technical team
Communicate design, requirements, functionality and limitations of systems/applications
Lead by example driving engineering expertise across the full stack TMUS technology portfolio.
Develop and drive a technical community across the organization that fosters innovation, agile development and test methodology, flexible teaming, knowledge sharing and talent transformation.
Provide technical leadership, inspiration and guidance to this growing development team; foster a culture of transparency, collaboration and innovation.
Translate business, and functional requirements into documented technical and architectural specifications.
Designs and develops APIs and microservices as required to deliver new digital functionality supporting enterprise business initiatives
Facilitate/lead reviews (walkthroughs) of technical specifications and program code with other members of the technical team, communicating design, requirements, feature set, functionality and limitations of systems/applications to team and development lead.
Hands-on code, build, automate, setup, configure, transform their given area
Build APIs, open source plug-ins and self-service tools to invoke and integrate capabilities, platforms, solutions
Utilize planning and leadership skills to oversee development deliverables as required to implement new systems capabilities.
Contribute to and work to meet project schedules by providing accurate estimates of effort required for development deliverables, by providing updates on project progress to development and project management, and by escalating issues that might affect project success to management.
Utilize development skills to build (code) and unit test new systems functionality per technical specifications, with deliverables to include code builds and documented unit test results.
Identify new approaches to complex design problems (federated identity, complex event processing, embedded real-time and cooperating ecosystems, etc.).
Influence non-technical aspects of technology change (e.g. business and operational architectures).
Collaborate with other teams including Business, Architecture, Enterprise Testing, Release Management, Project Management and Application Support for successful delivery of systems enhancements.
Lead automation of operational processes in support of SDLC tools to enable self-service and self-governance
Develop application support documentation as required by the application support teams for acceptance of systems changes into production.
Build and unit test production deployment packages and implementation plans for scheduled systems enhancements.
Utilize departmental Digital Development Lifecycle Methodology as a guide for development activities.
Provide on call and after-hours support as required for production releases and to respond and provide support on production outages.
Maintain technical skills and expertise through continuing education and training.


5-10 years of progressive experience in software engineering
Has had technical leadership experience on at least 5 large scale projects, providing leadership to at least 4 developers on each project, with projects impacting multiple business units and with development timelines greater than 4 months each.
Demonstrated ability to plan and execute highly visible, cross business initiatives ; valued as a trusted partner with Technology Executives.
Highly competent in at least TWO of the following languages and expert: Java, Python, C#, VB.NET or Objective-C.
Expert in at least THREE of the following domains: public cloud (AWS/PCF), server-side web dev, client-side web dev, REST/web services.
Experienced with CICD concepts and Jenkins pipelines.
Has experience developing cloud native apps using Spring Boot. Well versed in container technologies like docker .
Good knowledge of service virtualization concepts with experience on specific tools like CA service virtualization and spring cloud contract.
Has experience writing BDD (Behavioral Driven Development) test cases.
Has experience using monitoring tools like AppDynamics, Splunk and Grafana.
Has experience mentoring other members of technical/development staff.
Has experience providing production support for cloud-based digital applications and services.
Strong verbal presentation and written communication skills

Company Profile:

As America's Un-carrier, T-Mobile USA, Inc. (NASDAQ: TMUS) is redefining the way consumers and businesses buy wireless services through leading product and service innovation. The company's advanced nationwide 4G and 4G LTE network delivers outstanding wireless experiences for customers who are unwilling to compromise on quality and value. Based in Bellevue, Washington, T-Mobile USA. Inc. provides services through its subsidiaries and operates its flagship brands, T-Mobile and Metro by T-Mobile. For more information, please visit

EOE Statement:

We Take Equal Opportunity Seriously - By Choice. 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, 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 or harassment based upon any of these factors is wholly inconsistent with our Company values and will not be tolerated. Furthermore, such discrimination or harassment may violate federal, state, or local law.

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