Senior Fullstack Engineer — Growth & Checkout Platforms

Overflow; United States; Hybrid; USD 120,000 - 190,000; Full time

Benefits offered by this job

Competitive base salary with equity

Medical, dental, and vision coverage

Generous paid time off

Paid parental leave

401(k) retirement plan

Mental health stipend

Team retreats and in-person gatherings

Job summary

Overflow is a Series C fintech and SaaS platform empowering nonprofits and mission-driven institutions to grow generosity at scale. We seek a Senior Fullstack Engineer on the Growth team to architect self-service onboarding, seamless plan upgrades, and high-converting checkout experiences across new e-commerce touchpoints.

You will work at the intersection of engineering, product, and revenue to transform complex requirements into reliable, scalable features.

Qualifications

• 5+ years of fullstack software engineering experience.
• Strong proficiency in React, TypeScript, and Node.js.
• Deep experience designing scalable RESTful APIs and relational databases.
• Strong product sense and understanding of product-led growth mechanics, conversion funnels, and user-centric design.
• Leadership and ownership with ability to drive architectural decisions.

Responsibilities

• Architect and build end-to-end Product-Led Growth features enabling self-onboarding and plan upgrades.
• Own features from database schema to RESTful API design and frontend implementation (React/TypeScript).
• Write clean, well-tested code and contribute to engineering standards and reviews.
• Collaborate with Product, Design, and Data; run experiments and iterate to improve conversion.
• Identify technical debt and contribute to architectural improvements for Growth surfaces.
• Mentor junior engineers and participate in on-call rotations to ensure system reliability.

Skills

Fullstack engineering

React

TypeScript

Node.js

RESTful APIs

Relational databases

Product-led growth

Leadership

Job description

Overflow is a Series C fintech and SaaS platform empowering nonprofits and mission-driven institutions to grow generosity at scale. We seek a Senior Fullstack Engineer on the Growth team to architect self-service onboarding, seamless plan upgrades, and high-converting checkout experiences across new e-commerce touchpoints.

You will work at the intersection of engineering, product, and revenue to transform complex requirements into reliable, scalable features.