Backend Software Engineer, Flex
$161-194k
Salary dependent on location + Company equity
Flexible rent payment application
Be an early applicant
Flexible rent payment application
501-1000 employees
Be an early applicant
$161-194k
Salary dependent on location + Company equity
501-1000 employees
Company mission
Flex's mission is to empower as many renters as possible with flexibility over their most significant recurring expense.
Role
Who you are
- Strong computer science fundamentals and passion for building scalable backend systems
- 2–3+ years of professional software engineering experience with a focus on backend services
- Proficient in Java with hands-on experience using Flex’s core stack: Spring (core/web/boot), Gradle, JUnit
- Experience building and maintaining distributed services and APIs at scale in production environments
- Familiar with REST API design, mobile API best practices, and service-oriented architectures
- Experience building fault-tolerant systems with multiple external dependencies
- Skilled in observability and monitoring tools (e.g., DataDog) to ensure high availability
- Ability to write high-quality code that is testable, maintainable, scalable, and secure
- Demonstrated ability to translate business requirements into technical specifications and deliver high-impact solutions
- Excellent communicator who thrives in a collaborative, globally-distributed team environment
- Comfortable working with both technical and non-technical stakeholders and setting expectations on scope and delivery
What the job involves
- Flex is hiring Software Engineer II, Backend roles across three different engineering teams: Consumer, Partner Integrations, and Core Platform
- When you apply, you will automatically be considered for all three positions, and your placement will be determined based on your experience and expertise assessed during the interview process
- As a Backend Engineer at Flex, you will be responsible for designing, building, testing, and scaling backend services and APIs that power our consumer products, partner integrations, and core business systems
- You’ll work closely with product, design, and engineering peers to solve renters’ most pressing problems and deliver delightful user and partner experiences
- You will own the full lifecycle of your services- from scoping and architecture to deployment and monitoring, and will roll out changes in an agile, iterative manner to deliver impact quickly
- Consumer Engineering: Builds the APIs and backend systems that power Flex’s main consumer-facing products
- This team focuses on delivering scalable services that drive a seamless rent payment experience through our mobile and web apps
- Partner Engineering: Focuses on our partner integrations platform and partner-facing experiences
- This team owns the backend services and external integrations that connect Flex to financial and other third-party partners to ensure reliable, secure rent payment flows
- Core Platform Engineering: Builds and maintains the backend systems and infrastructure that support all business features, including Payments, Billing, Identity, and Partner Integrations
- This team ensures Flex’s foundation is robust, scalable, and secure
- Design, develop, test, and scale backend services and APIs that power Flex’s products, partner experiences, and internal platforms
- Implement the service APIs used by our mobile and web apps to simplify complex rent payment processing
- Build robust, fault-tolerant systems that integrate with multiple external dependencies and ensure high reliability
- Work closely with cross-functional teams—including Engineering, Product, Design, Infrastructure, Sales, Partner, and Customer Success—to deliver features and integrations that wow both customers and partners
- Translate feature requirements into well-structured technical specifications and scalable solutions
- Lead scoping, design, and implementation for the APIs you build and drive production rollouts with minimal oversight
- Contribute to service-oriented architecture, scalable system design, and internal best practices for distributed services environments
- Collaborate with peers to evolve Flex’s technical architecture as the company and product offerings grow
- Ensure services are observable and highly available through effective use of monitoring tools and practices
- Participate in code reviews, CI/CD improvements, and efforts to increase code quality and stability
Our take
Many people struggle to pay their rent every month, with a variety of bills hitting their bank accounts simultaneously. Whilst many of these people earn enough money to cover their bills, the inflexible nature of monthly bills can make the all-in-one payment a harder obstacle.
Flex provides a mobile application for the flexible payment of rent, allowing users to pay their landlords through flexible payment plans, reschedule payments when necessary, and protect their funds through Overdraft Protection. The company achieves this by partnering with estate agents and paying their resident's bills upfront, taking on the challenges that landlords would normally have due to late payments.
Flex has experienced extremely rapid growth since its founding which has caused some issues, as it struggled to keep up with the surge in new customers. Having made improvements to its product and scaled its customer service team, it is set to continue providing a service that has come to be highly valued by both tenants and landlords.
Freddie
Company Specialist at Welcome to the Jungle
Insights
10% employee growth in 12 months
Company
Funding (last 2 of 5 rounds)
Feb 2022
$160m
SERIES C
Apr 2021
$46.6m
SERIES B
Total funding: $225.1m
Company benefits
- 100% company-paid medical, dental, and vision
- 401(k) + company stock options
- Unlimited paid time off + company paid holidays
- Parental leave + IVF and adoption support
- Flex Cares Program: Non-profit company match + pet adoption coverage
- Pet Insurance
- Free Flex subscription
Company HQ
Midtown Manhattan, New York, NY
Leadership
Shragie Lichtenstein
(CEO)Experience working in venture capital investments for Point72 and TVC. Also co-founded Boundless Reality.
YeTong Shao
(CPO)Experience as Data Science Researcher. Also co-founded Boundless Reality.
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