US Mobile

Principal Software Development Engineer in Test

Posted 8 Days Ago

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2 Locations

Hybrid

140K-180K Annually

Senior level

Internet of Things • Mobile • Other • Software

We’re on a mission to revolutionize connectivity. We're building the next-generation connectivity platform.

The Role

The Principal SDET will lead the automation strategy, mentor engineers, manage CI pipelines, and ensure software quality in a fast-paced environment, focusing on modern microservices and cloud systems.

Summary Generated by Built In

US Mobile is on a mission to revolutionize connectivity. Imagine a world where you can go into a single app and buy terabytes of data for every one of your devices: phone, smart devices, car, home broadband, and more. That’s the future that US Mobile is building: a software platform built truly for the 21st century and the age of 5G and IoT, with world class engineering, best-in-class user experience, and features that will define the next generation of connectivity.

At the core of it all, we have a team and culture that has been recognized by Forbes as one of the top 500 best startup employers in the US. Our team spans diverse backgrounds, cultures, and stories, with employees coming from 20+ countries.

We’re a venture-backed company entering hyper-growth, having recently ranked 94th on Inc 5000’s fastest-growing private companies in America, and we’re looking for someone exceptional to join our team.

US Mobile is looking for a Principal-level SDET to own and elevate our quality engineering practice. This is a technical leadership role for someone who has built, scaled, and stabilized automated test platforms in modern microservices environments.

You’ll lead by example, designing test strategy, improving CI pipelines, mentoring engineers, and ensuring quality is embedded across the SDLC.

Technical Leadership:

Own test architecture and automation strategy across backend and frontend systems.
Design, build, and maintain scalable automated test frameworks.
Lead end-to-end, API, integration, and UI automation.
Drive adoption of best-in-class testing practices

Hands-on Execution:

Build and maintain pipelines using Selenium, Playwright or Cypress. (Currently using Cypress)
API testing.
Improve test stability, performance, and execution time in CI/CD.
Actively debug flaky tests and CI failures

Platform & System Focus:

Test Java / Spring Boot microservices.
Validate async workflows (RabbitMQ).
Test data persistence layers (MongoDB).
Ensure quality in AWS-based distributed systems.
Partner with DevOps to improve pipelines and observability.

Mentorship & Influence:

Mentor Software Engineers on test design and automation.
Establish coding standards and review practices for test code.
Influence product and engineering leaders on quality risk and release readiness

Must Have:

5+ years in Quality Engineering / Test Automation.
Senior or Staff-level experience in a product-driven org.
Deep expertise with Selenium, Playwright, Cypress.
Strong Java background (writing production-quality test code).
Experience testing microservices & distributed systemsCI/CD experience (GitHub Actions, Jenkins, GitLab, etc.).
Strong Linux fundamentals.
Proven ability to lead and influence.

Strong Plus:

Contract testing (Pact or similar).
Performance testing experience.
Cloud-native testing in AWS.
Observability-driven testing (logs, metrics, traces).
Prior experience building QA orgs from messy to mature

Benefits:

Competitive salary
Flexible working hours
Supplemental health insurance
Professional development stipend
$500 wfh tech set-up reimbursement

Think you could be a good fit?? Apply to learn more!!

Top Skills

AWS

Cypress

Github Actions

Gitlab

Java

Jenkins

MongoDB

Playwright

RabbitMQ

Selenium

Spring Boot

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The Company

New York City, NY

131 Employees

Year Founded: 2014

What We Do

At US Mobile, we’re on a mission to revolutionize connectivity. We're building a next-generation connectivity platform to connect the next billion wireless devices onto nationwide 4G and 5G networks, including your phone, drone, car, watch, pet tracker, and everything in between. We’re accomplishing this by leveraging cutting-edge technology and forward-thinking UI design.

Whether it’s with our free high-speed international roaming, customizable perks, AI-facilitated plan savings, customizable plans, or real-time dashboards, we’re building the industry’s most delightful user experience all backed by our excellent customer service.

US Mobile’s 4G LTE network reaches more than 300 million Americans and includes international calling to over 200 countries and territories, but you will never hear from an operator at US Mobile. Our real, live Customer Support Representatives are available by phone or chat 24 hours a day, 7 days a week – to keep you connected, informed, and saving with US Mobile.