Staff 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 2026 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 Staff SDET at Flex, you will operate as a technical leader within the Quality Engineering team, shaping quality strategy, standards, and automation frameworks for major products and platforms. You will collaborate across engineering, product, and cross-functional stakeholders to solve complex quality challenges and drive initiatives that raise the bar for software reliability and efficiency across the organization.

What you’ll do

• Define and lead quality strategy and test automation direction for major products and platforms
• Architect, implement, and optimize scalable, maintainable automation frameworks across products and services
• Set best practices for advanced testing methodologies, test data generation, and data-driven testing
• Drive adoption of new tools and emerging technologies to improve testing effectiveness and coverage
• Lead and coordinate cross-team quality and automation initiatives with significant business impact
• Collaborate closely with senior engineering, product, and leadership stakeholders to align quality goals and strategies
• Provide technical leadership and mentorship to SDETs and engineers across multiple teams
• Identify and resolve large-scale, complex quality challenges, proactively anticipating risks and ambiguities
• Establish and enforce quality standards, best practices, and documentation across the organization
• Analyze and report on quality metrics, test coverage, and areas for continuous improvement
• Advocate for a culture of quality, continuous improvement, and technical excellence

Key qualifications

• Bachelor’s degree in Computer Science or related field, or equivalent experience
• 8+ years of experience in software quality engineering and test automation
• Expert-level proficiency in multiple programming languages and automation frameworks
• Advanced experience architecting scalable, maintainable automation solutions across products and platforms
• Expertise in advanced testing methodologies, test data generation, data-driven testing, and other industry emerging technologies
• Deep knowledge of CI/CD systems and infrastructure-as-code tools
• Strong skills in test framework optimization and technical leadership
• Experience with enterprise-level observability, monitoring, and analytics tools
• Proficiency in complex data analysis and advanced SQL
• Excellent communication, influence, and cross-team mentorship abilities
• Ability to set and enforce quality standards and best practices at scale

Compensation

Flex takes a market-based approach to pay, and compensation may vary depending on your primary work location. Work locations are categorized into one of three tiers based on a cost of labor index for that geographic area. The successful candidate’s starting pay will be commensurate with their experience, qualifications, and Flex’s internal leveling guidelines and benchmarks.

Tier 1 (NYC/Bay Area, Los Angeles, Seattle)

$160,000—$200,000 USD

Tier 2 (Austin, Washington D.C. Philadelphia, San Diego, Chicago, Atlanta)

$144,000—$180,000 USD

Tier 3 (Salt Lake City, all other USA cities)

$136,000—$170,000 USD

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.

Offices

Roles posted in New York, San Francisco, and Salt Lake City are hybrid positions with on-site expectations of 2-3 days per week in our local offices. For candidates outside of these areas, you may be eligible for our relocation assistance program.

Benefits

For full-time U.S. employees we offer:

• Competitive medical, dental, and vision
• Company equity
• 401(k) plan with company match 
• Unlimited paid time off + 13 company paid holidays
• Parental leave 
• Free Flex subscription

 For full-time non-U.S. employees, we offer:

• Competitive compensation + company equity
• Unlimited PTO