Senior Full Stack Software Engineer at Kickoff

At Kickoff we’re building an AI-powered wellness super app that brings exercise, nutrition, sleep, and mindfulness together in one place, pairing daily personalized recommendations with real human coaching so people can form lasting healthy habits. We’re a mission-driven team helping shift healthcare toward prevention, and we’re looking for a senior engineer who wants to shape both our product and our culture from our NYC office.

What is this role?

This is a full-time, on-site Senior Full Stack Software Engineer position based in New York City. We’re seeking someone with senior-level experience who is ready to take ownership of major initiatives that combine modern web and mobile technologies with the latest advances in generative AI.

What will you do?

• Spend the majority of your time building and iterating on large-scale features that directly improve how clients form healthier habits and how coaches deliver results.
• Work with product, design, and fellow engineers to analyze user data, conduct quantitative research, and turn insights into new product directions.
• Apply generative AI, machine learning, and other emerging tools to create delightful client experiences such as smarter exercise and nutrition plans, gamified social dashboards, and automated coach-facing tools.

What makes you a great fit?

You bring at least four years of full-stack experience and are highly proficient with JavaScript, React, React Native, Node, and Next.js. Strong analytical thinking paired with solid SQL skills helps you turn data into actionable improvements. You thrive in fast-moving startup environments, enjoy collaborating closely with product and design teams, and are comfortable shipping minimalist MVPs when you have clear context on user and business needs. A genuine passion for fitness and wellness means you care deeply about the real-world impact of the code you write. Bonus points if you have hands-on experience with generative AI or LLMs, GraphQL, serverless architectures, or AWS-based DevOps.

What's in it for you?

You’ll join a team that values 10x impact projects, continuous learning, mutual support, and radical ownership. We keep process light so you can focus on building, and we prioritize in-person collaboration that strengthens both the product and our culture. Every line of code you ship helps clients become healthier and coaches create meaningful opportunities-all while advancing preventive health on a global scale.