Senior Backend Software Engineer, Flex
$146.2-212k
Salary dependent on location + Equity
More information about location
Flexible rent payment application
Be an early applicant
Flexible rent payment application
501-1000 employees
Be an early applicant
$146.2-212k
Salary dependent on location + Equity
More information about location
501-1000 employees
Company mission
To help people pay for the things that matter most.
Role
Who you are
- 6+ years of software engineering experience, with at least 4 years of hands-on Java development
- Proficiency in Java frameworks and tooling including Spring (core/web/boot), Gradle, JUnit, and JVM tuning (memory, performance, GC)
- Experience designing and building robust, fault-tolerant systems with multiple external dependencies using Service-Oriented Architecture, REST APIs, and message queues
- Hands-on experience with AWS services (EKS, Aurora RDS, ElastiCache, DynamoDB) and containerization tooling
- Comfort working on a globally distributed team with a high degree of ownership and strong stakeholder communication skills
- Experience with CI/CD systems (preferably GitHub Actions), git, and automation practices
- Familiarity with observability and monitoring tools such as Datadog to maintain high availability
- Consistent use of AI-assisted development tools (code generation, test writing, documentation) with full ownership of correctness, security, and quality
What the job involves
- Flex is hiring a Senior Engineer to join our backend engineering team, where you'll be responsible for designing, building, and scaling the systems that power our core products — including Payments, Billing, Identity, and partner integrations
- You'll work on services that directly shape how hundreds of thousands of renters experience financial flexibility, and your work will have a measurable impact on the reliability and performance of everything we ship
- In this role, you'll own meaningful portions of our backend infrastructure end-to-end — from scoping and API design through production rollout — with the autonomy to make independent technical decisions that drive real customer and business impact
- You'll collaborate closely with product, design, and engineering peers in an agile environment that favors small, frequent iterations over big-bang releases
- The ideal candidate is comfortable leading without being asked and takes pride in shipping high-quality, fault-tolerant systems
- At Flex, engineers are expected to bring both technical depth and a builder's mindset
- You'll be working within a globally distributed team, partnering with technical and non-technical stakeholders alike, and contributing to a codebase that scales with an ambitious product roadmap
- If you thrive in fast-moving environments and want your engineering work to directly improve how people pay rent, this role is for you
- Own multiple backend team goals and projects, delivering on time and with high quality with minimal oversight
- Design, build, and scale backend services and APIs across core domains including Payments, Billing, Identity, and partner integrations
- Make independent technical decisions that maximize customer and business impact, balancing speed with long-term system health
- Write elegant, well-tested code and provide constructive, thorough code reviews that elevate team standards
- Lead scoping and design discussions for new features and systems, driving production rollouts to completion
- Integrate AI-assisted development tools into your daily workflow as a default, and mentor teammates on responsible and effective AI usage
- Partner with product, design, and cross-functional engineering peers to solve high-priority user problems around rent payment
- Contribute to observability, reliability, and performance standards across the services you own
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
- Medical, Dental & Vision: Your healthcare will be available from Day 1— giving you immediate peace of mind — with best in class coverage and options.
- Parental Leave: Step away with paid time off to focus on family and life’s newest chapter.
- NYC HQ: Collaborate in our lively New York headquarters, with new office space on the way!
- 401(k) Retirement Savings: Plan ahead with our 401(k) program to grow your future. And starting early 2026, employees will be eligible for a company match!
- Flex Giving: Flex Giving empowers employees to support local nonprofits advancing housing stability in the communities we call home.
- Employee Assistance Fund: Confidential financial support to teammates facing unexpected hardships or emergencies.
- Hybrid Work Policy: Work flexibly from home, with in-person collaboration and events that matter.
- Unlimited PTO + Holidays: Take the time you need— whether that’s a vacation, recharge, or simply a long weekend
- Free Flex Subscription: As a Flex employee, you'll have full access to our services without charge.
- GrubHub Credit: Enjoy meal credits while in the office, so you’re fueled for the workday ahead.
Company HQ
Midtown Manhattan, New York, NY
Leadership
Shragie Lichtenstein
(Co-Founder & CEO)Prior to co-founding Flex in 2019, Shragie co-founded Boundless Reality. They graduated from Yeshiva University in 2015 with a Bachelor's Degree in Finance.
YeTong Shao
(Co-Founder)Prior to co-founding Flex in 2019, YeTong co-founded Boundless Reality alongside Shragie. They graduated from the University of Chicago with a Bachelor's Degree in Mathematic & Economics.
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