Senior Fullstack Engineer
Overflow
Senior Fullstack Engineer
Overflow
Donations platform for stocks and crypto
Overflow is a Series C, growth-stage technology company on a bold mission: to inspire the world to give. We're a vertical fintech and SaaS platform unlocking more ways to give — cash, stock, crypto, and beyond — through a beautifully designed ecosystem built for high-impact churches, nonprofits, and mission-driven institutions.
Backed by Uncork Capital, Craft Ventures, Salesforce Ventures, R7, and WIF (one of the largest lenders to faith and philanthropic organizations in the country), we're building the infrastructure that makes generosity frictionless at scale.
Overflow was founded on the belief that generosity transforms people and communities. Inspired by Proverbs 11:24 — "The world of the generous gets larger and larger" — we operate with integrity, stewardship, service, and excellence.
Overflow operates with a flexible work model. While there is no company-wide in-office requirement, some teams may establish in-person collaboration rhythms based on their function, goals, and team needs.
We maintain offices in Los Gatos, CA and Birmingham, AL for team collaboration, coworking, meetings, and intentional in-person connection.
As a Senior Fullstack Engineer on our Growth team, you will be the technical engine behind our Product-Led Growth (PLG) initiatives. Your work will directly impact how organizations discover, adopt, and expand their use of Overflow.
You will design and build the critical pathways that allow our customers to scale their generosity effortlessly. This includes architecting seamless self-service onboarding flows, creating frictionless plan upgrade paths, and standing up high-converting checkout experiences across new e-commerce touchpoints. You will sit at the intersection of engineering, product, and revenue, turning complex business requirements into intuitive, reliable, and scalable product features.
Drive Product-Led Growth: Architect and build robust, end-to-end features that enable intuitive customer self-onboarding, seamless subscription plan upgrades, and highly optimized e-commerce checkout flows.
Full-Stack Ownership: Own complete features from database schema and RESTful API design (Node.js) through to a polished, highly responsive frontend implementation (React/TypeScript).
Engineering Excellence: Write clean, well-tested, and maintainable code, actively contributing to engineering standards and rigorous code reviews.
Cross-Functional Collaboration: Partner closely with Product, Design, and Data to iterate quickly, run experiments (A/B tests), and deliver high-quality user experiences that drive conversion.
Architectural Strategy: Identify technical debt and contribute to architectural improvements that enhance the reliability, scalability, and speed of our Growth product surfaces.
Mentorship & Reliability: Mentor junior engineers, help elevate the team's technical capabilities, and participate in on-call rotations to ensure the high availability of our systems.
Core Experience: 5+ years of fullstack software engineering experience
Technical Stack: Strong proficiency in React, TypeScript, and Node.js (or similar modern backend technologies).
Systems Design: Deep experience designing and building scalable RESTful APIs and working with relational databases.
Growth Mindset: A strong product sense and an understanding of product-led growth mechanics, conversion funnels, and user-centric design.
Leadership & Ownership: Demonstrated ability to lead technical initiatives, make sound architectural decisions, and operate with a strong accountability mindset.
E-commerce & Billing Experience: Hands-on experience integrating with billing and subscription platforms or building custom e-commerce checkout experiences.
Fintech Context: Experience in fintech, payments infrastructure, or donation platforms.
Startup DNA: Experience at a Series B or growth-stage startup, thriving in a fast-paced, iterative environment.
The base salary range for this position is $120,000 – $200,000, based on Carta Total Compensation benchmarks for role, geography, and function. Total compensation may also include equity, performance-based bonuses (for eligible roles), and a comprehensive benefits package.
Competitive base salary with equity eligibility
Medical, dental, and vision coverage for employees and dependents
Generous paid time off and company holidays
Paid parental leave
401(k) retirement plan
Dedicated mental health and therapy stipend to support personal well-being
Team retreats and intentional in-person gatherings throughout the year
Overflow is proud to be an equal opportunity employer and is committed to building a diverse and inclusive team.
Overflow helps churches and nonprofits accept and manage donations of non-cash assets like stocks and cryptocurrency, alongside cash gifts, through a subscription-based financial technology platform. Donors can give via multiple channels (card, ACH, stock, crypto, and donor-advised funds), and Overflow processes these gifts while providing automated giving statements, live dashboards, and detailed donor and gift-status tracking. The platform focuses on reducing barriers to giving and offering low processing fees, aiming to stand out with a comprehensive, end-to-end solution for charitable fundraising. Overflow’s goal is to make generosity frictionless and to significantly increase charitable contributions by unlocking and simplifying the use of non-cash wealth, which makes up a large portion of global assets.
Explore more opportunities at Overflow