Job Details

Senior Software Development Engineer in Test (SDET)

Flex is a growth-stage, NYC headquartered FinTech company that is creating the best rent payment experience. It's hard to believe that it's 2025 and paying rent on time is expensive, inflexible, and difficult. We're here to change that. Flex enables our users to pay rent throughout the month on a schedule that better fits their finances and budget. Our mission is to empower as many renters as possible with flexibility over their most significant recurring expense. After deliberately keeping a stealth profile as we built up unprecedented investor support and an enthusiastic user base, we are looking for motivated individuals to help us keep our mission growing. Will you be a part of the team?

About the role

As a Senior SDET at Flex, you will own the test automation and quality efforts for entire product areas or major features. You will architect and optimize automation frameworks, lead test strategy for complex systems, and regularly collaborate across teams to deliver reliable and high-quality releases. This role offers the opportunity to mentor others, drive cross-functional quality improvements, and play a critical part in shaping the future of our engineering excellence.

What you'll do

• Architect, implement, and optimize automated test frameworks for complex product areas, ensuring high reliability and maintainability
• Design, develop, and maintain robust automated test suites for API, UI, and integration testing
• Lead test strategy development and perform risk analysis for major features and systems
• Integrate automated testing into CI/CD pipelines, supporting continuous integration and delivery processes
• Proactively identify systemic quality issues and drive cross-team process improvements to increase coverage and efficiency
• Analyze test coverage, identify gaps, and implement solutions to improve product quality
• Collaborate closely with engineering, product, and quality leaders on cross-functional quality initiatives and release planning
• Provide technical guidance and mentorship to junior SDETs and QA team members, fostering skill development and best practices
• Review code and test cases contributed by other engineers for quality and maintainability
• Maintain accurate and actionable test documentation, reports, and quality metrics for assigned product areas
• Investigate and resolve complex defects and production issues through advanced debugging and root cause analysis
• Advocate for quality and champion adoption of best practices within and across engineering teams
• Proven ability to lead test strategy and risk analysis while making high-impact technical decisions amid ambiguity and prioritizing what matters most

This is a hybrid position with on-site expectations of 3 days per week in our New York City Headquarters (Union Square) or Bay Area (San Mateo). For candidates outside of these areas, you may be eligible for our relocation assistance program.

The compensation range for this role will be commensurate with the candidate's experience and Flex's internal leveling guidelines and benchmarks.

Life at Flex

We understand that it takes a diverse team of highly intelligent, curious, determined, empathetic, and self aware people to grow a successful company. Our HQ is located in New York City, but we have employees located throughout the US, Australia, Canada and South America. We are growing quickly, but deliberately, with a focus on building an inclusive culture. Our dynamic team has incredible perspectives to share, just as we know you do, and we take great pride in being an equal opportunity workplace.

We offer many employee benefits. For full time, U.S. based employees we offer:

• Competitive pay
• 100% company-paid medical, dental, and vision
• 401(k) + company equity
• Unlimited paid time off + 13 company paid holidays
• Parental leave
• Flex Cares Program: Non-profit company match + pet adoption coverage
• Free Flex subscription

For full time non-US employees, we offer

• Competitive Pay
• Company Equity
• Unlimited PTO

Voluntary Self-Identification

For government reporting purposes, we ask candidates to respond to the below self-identification survey. Completion of the form is voluntary and will not affect your candidacy. Any information provided will be kept confidential.

As set forth in Flex's Equal Employment Opportunity policy, we do not discriminate on the basis of any protected group status under any applicable law.

If you believe you belong to any of the categories of protected veterans listed below, please indicate by making the appropriate selection. Because Flex is a government contractor subject to VEVRAA, we request this information to measure outreach and recruitment efforts. Categories are described in the original form and may include protected veteran classifications.

Disability status and voluntary self-identification of disability information are provided as part of OFCCP requirements. Completing this form is voluntary, and your answers are confidential. More details are available in the form accompanying this posting.