Kikoff
Senior Fullstack Engineer - User Retention & App Ecosystem
About this role
Kikoff: The Fintech Powering Financial Security at Scale
Kikoff is a profitable, pre-IPO fintech company on a mission to empower everyone to achieve financial security. With record revenue growth in 2025 and a unicorn valuation, we've built a suite of products that help millions of people build credit, access liquidity, and save money.
We're scaling fast. Join us if you want to build something meaningful and help millions of people move forward financially.
Why Kikoff
This is a consumer fintech startup, and you will be working with serial entrepreneurs who have built strong consumer brands and innovative products. We value extreme ownership, clear communication, a strong sense of craftsmanship, and the desire to create lasting work and work relationships. Yes, you can build an exciting business AND have real-life real-customer impact.
About the team
The User Retention and App Ecosystem team focuses on sustainable, long-term, and interconnected customer growth at Kikoff. We help customers stay around longer and get more value from their subscriptions. We ensure that customers are excited to explore the different consumer fintech apps across Kikoff’s growing ecosystem, with as little cross-app friction as possible.
We’re looking for a Senior Fullstack Engineer to drive user-facing projects, improve existing core services, and own product domains. If you like owning both the work and the outcome of a complex project end-to-end, we’d like to talk to you!
What you’ll be doing
- Lead and implement data-driven and impact-focused projects around user-retention and ecosystem integration end-to-end, affecting millions of users.
- Be the definitive technical owner for 1 to 2 large product areas across credit report retrieval, credit disputes, customer off-boarding experience, and cross-app integration.
- Enhance observability, reliability, and operational excellence across existing services.
What we’re looking for
- B.A. / B.S. / M.S. or strong self-taught fundamentals in computer science
- 6+ years of industry experience, or high-slope growth, with demonstrated breadth and depth of product impact
- Strong fullstack development experience with a backend focus: proficient or highly proficient on the backend, and experienced in either web frontend (React) or mobile (Flutter preferred)
- Strong cross-functional communication and coworking skills with product, data, design, and legal partners
- Demonstrated ability to own and drive complex projects end-to-end, coordinating focused teams through ideation, requirements, design, implementation, launch, and post-launch.
- Good judgment in identifying and choosing trade-offs between business impact, delivery speed, and long-term operational excellence
- Strong system design skills for both new and existing systems
An ideal candidate also shows
- Experience with financial infrastructure or regulated environments (credit bureau data, PII, SOC2)
- Background in fintech, payments, or lending infrastructure
- Experience integrating third-party APIs reliably and communicating with technical vendors
- Experience with classical ML model training and production deployment
- Experience with observability, monitoring, and alarms in customer-facing systems
- Experience with using business metric focused A/B tests and experiments for new features
- Experience in leveling up the team through code reviews, design docs, and technical guidance
- Thoughtful use of AI tools to accelerate delivery while maintaining operational excellence
- Eagerness for product and feature ideation
- Experience with our stack is a plus: Ruby on Rails, React, Flutter, MySQL
Equal Employment Opportunity Statement
Kikoff Inc. is an equal opportunity employer. We are committed to complying with all federal, state, and local laws providing equal employment opportunities and considers qualified applicants without regard to race, color, religion, creed, gender, national origin, age, disability, veteran status, marital status, pregnancy, sex, gender expression or identity, sexual orientation, citizenship, or any other legally protected class.
Please reference the following for more information.
Written by Kikoff. Original job post
Skills mentioned
- Backend
- Flutter
- Frontend
- Machine Learning
- MySQL
- Rails
- React
- Ruby
- System Design
Opens the application — the Jobs AI extension fills it for you. Set up autofill
Opens the official application on the employer’s site. No login required.
Kikoff
Kikoff is a fintech startup that builds financial products and internal AI-powered tooling to support its operations. The company is hiring for systems engineering and infrastructure roles to manage its SaaS stack, identity systems, endpoint security, and automation workflows.
- Industry
- Technology & Software
Likely interview questions
- Describe a time you owned a complex project from ideation to launch, highlighting the challenges you faced and how you overcame them.
- How would you approach identifying and prioritizing user retention initiatives within a fintech product like Kikoff?