Senior Full-Stack Engineer, AI & Product (Python, Go, Flutte in MacrosFirst

MacrosFirst is building the world’s leading nutrition app to help people live healthier lives and achieve fitness goals through a balanced diet. We’re bootstrapped, profitable, and focused on scaling to eight-figure ARR while keeping the team small and nimble.

You’ll join a team of 6 engineers and work closely with the co-founders, design, marketing, and customers to craft features that move the needle for our engaged user base. The project slate centers on an AI-powered Nutrition Copilot, a multi-agent system using LLMs for real-time nutritional coaching, plus ongoing Flutter-based frontend efforts and backend evolution.

Send CV through getonbrd.com.

• You have a strong software engineering background, with at least 5 years of experience writing production code across frontend and backend.
• You have experience with AI orchestration frameworks (e.g., LangChain, CrewAI, or building custom agentic logic)
• You have a strong understanding of RAG and optimizing LLM performance through tool-calling and prompt engineering.
• You have experience building high-concurrency backends to support real-time AI interactions and data streaming.
• Advanced written and spoken English (C1)
• You thrive in fast paced, nimble startup environments.
• You have a demonstrable track record of shipping.
• You have an entrepreneurial mindset, whether you’ve created your own products, worked at startups, or have dreams to do so.
• You're hungry for impact and ownership, and you enjoy wearing multiple hats and learning new things.
• You consider yourself a generalist, not tied to any one technology, but excited to tackle new technical challenges.
• You have an appreciation and passion for great design, whether product, brand, or UI.
• You feel confident making decisions amid ambiguity.