Fullstack Developer
€4,650 - €5,800
As a Senior Fullstack Developer, you will be a key contributor to our core product, building and scaling features that are central to the donation experience for millions of users. You'll leverage your expertise in Node.js, React, and TypeScript to develop complex components—from dynamic donation widgets to data-driven admin dashboards—with a relentless focus on code quality, scalability, and user experience.
This is an ideal opportunity if you love solving real-world problems at scale and want to grow within a mission-driven, high-impact engineering culture.
What You’ll Do
Design, build, and maintain resilient frontend and backend features using React and Node.js.
Develop our core products, including donation checkouts, embeddable widgets, and donor/partner portals.
Architect and develop system components that scale across millions of monthly transactions.
Write clean, well-documented, and thoroughly testable code.
Drive architecture and technical design discussions to find elegant solutions to complex problems.
Mentor peers by conducting thoughtful code reviews and providing constructive feedback.
Partner with product managers and designers to clarify requirements and shape the roadmap.
Proactively identify and resolve bugs, performance bottlenecks, and optimization opportunities.
Requirements
7+ years of professional fullstack development experience.
Deep understanding of modern JavaScript (event loop, closures, promises, prototypes).
Expert-level proficiency with React and its ecosystem (familiarity with Vue is a plus).
Strong backend expertise with Node.js (experience with Koa or NestJS is highly preferred).
Experience with Webpack configuration, performance optimization, and profiling.
A keen eye for detail and a high sense of ownership and accountability for your work.
Nice to Have
Experience with MongoDB, ClickHouse, or Elasticsearch
Familiarity with Docker, CI/CD pipelines, or cloud infrastructure
Contributions to open-source projects or a strong personal portfolio
Bonus points
Curiosity and a hypothesis-driven mindset
Ability to communicate complex analytical concepts to non-technical audiences
Detail-oriented with a strong sense of ownership
Comfort working in fast-paced, data-rich environments
Why work with us
A strong, collaborative product team that owns what it builds
Clear product vision and access to real customer feedback from global nonprofit leaders
Flat structure: no politics, just great work with great people
Transparent company culture-we share how we’re growing, where revenue comes from, and what’s next
Long-term focus: we offer equity options and value sustained, meaningful contribution
Benefits
31 days off
100% paid telemedicine plan
Home Office Setup Assistance: the company offers assistance with purchasing furniture (office chair, office desk, monitor) and other items to create a comfortable workspace.
English learning courses
Relevant professional education
Gym or swimming pool
Co-working
Remote working.
Published on: 10/29/2025

Fundraise Up
Fundraise Up is an online donation platform that helps nonprofits engage more supporters and grow revenue by providing easy ways to increase conversion, enable modern payment methods, and personalize the giving experience for every donor.
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