Senior Full-Stack Developer (.Net and React)

About Us
JustAnswer is the leading AI + Human professional services platform, on a mission to revolutionize how people access expert help. Since 2003, we’ve connected millions of customers across 196 countries with verified professionals in real time—anytime, anywhere. With a powerful combination of human expertise and cutting-edge AI, we’re transforming the future of professional services.

Rooted in boldness, humility, and innovation, we take a data-driven approach to solving complex problems and continuously improving through Lean principles.

About the Role

As a Senior Full-Stack Developer, you will join a mission-critical initiative to build an AI-powered subscription platform for solo professionals (Fount.com). Fount is an independent product unit partially supported by JustAnswer, and you’ll join its core delivery team. We’re developing a category-defining toolset that helps experts get leads, manage communications, and grow their businesses — all enhanced by intelligent AI assistants.

You’ll work across the full stack (.NET Core/C# + React.js), helping build new features like an auction system for lead bidding, expert/customer chats, contracts, and billing tools. Much of the work is greenfield (from the scratch), and you’ll play a key role in defining scalable architecture and shipping impactful features.

What You’ll Do

• Design, develop, and maintain full-stack applications, backend logic modules, and front-end experiences using React.js and .NET Core.
• Collaborate with Product, UX, and Engineering stakeholders to clarify requirements and contribute to technical planning and documentation.
• Conduct code and design reviews, provide architectural input, and mentor junior developers on best practices.
• Write and maintain automated unit and integration tests using tools such as Jest, NUnit, or Playwright.
• Monitor and support production systems, resolve bugs, run performance audits, and ensure system stability.
• Contribute to the implementation of AI-driven features, including prompt-based workflows, RAG pipelines, and personalized assistant flows.
• Continuously improve code quality, team velocity, and system reliability through thoughtful technical decisions and rapid iteration.

What We’re Looking For

• 5+ years of commercial experience in full-stack software development.
• Strong proficiency in .NET Core, C#, and React.js (or deep experience in another modern frontend framework and readiness to learn React).
• Experience building and consuming REST APIs, and working with asynchronous backend services.
• Familiarity with modern automated testing frameworks (Jest, NUnit, Playwright, etc.).
• Comfortable working in a CI/CD environment with agile delivery cycles.
• Basic database knowledge and familiarity with performance and scalability considerations.
• Proven ability to work independently, own projects end-to-end, and make architectural tradeoffs.
• Upper-Intermediate English or higher for effective communication with international stakeholders.
• Curiosity and interest in AI-powered applications and emerging technologies.

Why Join Our Team
At JustAnswer, we blend the best of AI and human expertise to make a real impact. Our mission-driven culture values bold ideas, continuous learning, and global collaboration. We offer a flexible, remote-first environment with equitable rewards, career growth opportunities, and a supportive community where your contributions truly matter. Join us and be part of something bigger, helping people, one answer at a time.

Our JustAnswer Promise
We strive together to make the world a better place, one answer at a time. JustAnswer's mission is to help people. We do this by connecting our members with verified Experts to help answer life's questions and solve problems. It’s not every day in your life that you get to be a part of a simple yet powerful mission. We pride ourselves in doing things the JA Way.
• Data driven: Data decides, not egos
• Courageous: We take risks and challenge the status quo
• Innovative: We're constantly learning, creating, and adapting
• Lean: We focus on customers, using lean testing to learn how to serve them best
• Humble: Past success is not a guarantee of future success
If these things matter to you, come join the team here at JustAnswer!

Our Commitment to an Inclusive Workplace
We welcome people from all backgrounds who seek the opportunity to help build a future where professional services are readily available to all. If you have curiosity, passion, and a collaborative spirit, come work with us. JustAnswer is committed to an inclusive workplace. JustAnswer is an equal opportunity employer and does not discriminate on the basis of race, national origin, gender, gender identity, sexual orientation, disability, age, or other legally protected status.

AI Disclosure & Informed Consent
Artificial intelligence (AI) technology may be used during the hiring process to record, transcribe, analyze, and rank interview responses. By submitting your application and participating in the interview process, you acknowledge and consent to the use of AI technology in the hiring process. For more information see our AI Disclosure and Consent Policy.