Senior Fullstack Engineer - User Retention & App Ecosystem
Kikoff
$244,000 - $292,000 / year
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Description
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
A note on applying: We know great candidates sometimes hold back if they don’t meet every qualification listed. If you’re excited about this role and believe you can do the work, we encourage you to apply. We’re looking for capability and trajectory, not a perfect checklist match.
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.
About this role
Kikoff's User Retention and App Ecosystem team is building the technical foundation that keeps millions of customers engaged across a growing suite of fintech products. As a Senior Fullstack Engineer here, you'd own 1–2 large product domains end-to-end—spanning credit report retrieval, credit disputes, customer off-boarding, and cross-app integration—and drive data-informed projects that directly affect user behavior and lifetime value. This means designing systems, shipping features, and improving reliability across services that touch real people managing their financial lives.
You'll need 6+ years of industry experience with demonstrated breadth in product impact, strong backend chops, and fluency in either React or Flutter on the frontend. The role demands genuine cross-functional collaboration with product, data, design, and legal teams, plus the judgment to navigate trade-offs between speed, business value, and long-term operational health. System design skills matter here—both for new services and hardening existing ones.
Fintech or regulated-environment experience is valuable but not required; what tips the scales is a track record of owning complex projects end-to-end, thoughtful integration of third-party APIs, and comfort with financial infrastructure concerns like PII and compliance. Familiarity with Ruby on Rails, React, Flutter, or MySQL is a plus. This is an in-office role in San Francisco, paying $244,000–$292,000 annually.
How this employer is doing
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Pay for this role
$244,000 to $292,000 per year
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