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Senior Software Engineer, Backend, Core Platform

USA flag USA


Posted 12 days ago

Job Type

Full Time


$160k - $210k




  • Mission/Vision: Transform rent payment to be flexible, affordable, and user-friendly.

  • Key Responsibilities: Design, develop, and scale backend systems and services, ensuring high availability and reliability.

  • Growth Opportunities: Lead projects, mentor junior team members, and implement best practices.


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 2024 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?

Flex is looking for a Senior Software Engineer who will be responsible for implementing the platforms and APIs that support all business features.

In this role, you will be part of the Core Platform team, responsible for the backend systems and services that power our products, such as Payment, Ledger, Identity, etc. You’ll be designing, developing, testing, and scaling the platform needed to deliver great user and partner experiences and a reliable end-to-end payment process.

You’ll work closely with your product, design and engineering peers to solve our users' most pressing problems around rent payment. You’ll roll out changes to our customers in an agile manner with a delivery cadence that favors small, frequent iterations. The ideal candidate will be comfortable leading scoping, design and implementation for APIs they build and can drive their production rollouts to completion with minimum oversight.

A minimum of 4 years of experience with Java is required for this position.

Who you are:

  • You have strong computer science fundamentals

  • You have experience to translate the feature requirements into technical specifications.

  • You have experience leveling up the entire team’s bar by introducing best practices, mentoring junior people, etc.

  • You have experience with the Java frameworks and tools we use at Flex such as Spring (core/web/boot), Gradle and JUnit

  • You have experience implementing and operating services in distributed services environments at scale

  • You have experience with observability and monitoring tools such as DataDog for maintaining high availability

  • You write high quality code that is testable, maintainable, scalable and secure

  • You have a good understanding of REST and mobile API best practices

  • You have great communication skills and are comfortable working with a distributed team

Core competencies:

  • Prior experience working on cross functional teams

  • Experience with leading the project in its entire lifecycle, from requirements gathering to delivery.

  • Proficient with Java and Spring (Bonus: AWS, Containers, Kubernetes, MySql)

  • Experience with CI/CD to improve code stability and code quality

The national pay range for this role is $160,000-$210,000. Individual compensation will be commensurate with the candidate's experience aligned with 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, 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 stock options

  • Unlimited paid time off with a PTO minimum + 13 company paid holidays

  • Parental leave

  • Flex Cares Program: Non-profit company match + pet adoption coverage

  • Free Flex subscription


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Healthcare benefits

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401(k) Match

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Stock Options

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Paid Leave

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Parental leave