Senior Full Stack Engineer at Messa — Argentina

About The Role

ROLE OVERVIEW

We're looking for a Senior Full Stack Engineer to help design, build, and ship core parts of our product. You'll work across the entire stack, with a strong emphasis on crafting polished, intuitive user experiences, while also building reliable backend systems and integrating AI deeply into the product.

We’re an early stage full of energy team. Everyone wears multiple hats, moves fast, and cares deeply about what we're building. We need someone with a product mindset: not just an engineer who executes specs, but someone who thinks about why we're building something and how users will experience it.

WHAT YOU'LL DO

Build and own end-to-end product features across the full stack.
Design and implement clean, high-performance user interfaces. This is where your craft shines.
Develop and maintain robust APIs and backend services.
Integrate AI agents and LLM-powered workflows into the product.
Participate in code reviews and help maintain a high quality bar across the codebase.
Think like a product builder: bring ideas, question assumptions, and help shape what we ship.

WHAT WE'RE LOOKING FOR

Must-haves

Expert-level proficiency in React and modern TypeScript.
Basic backend experience. You're comfortable designing APIs and working with server-side systems.
Sharp eye for UI/UX. You build interfaces that feel polished and intuitive, not just functional.
Experience working with AI/LLM tools in your workflow and integrating AI capabilities into product features.
Product mindset. You think about the user, not just the ticket.
High-quality code output with minimal review overhead.
Comfort with ambiguity and speed in an early-stage environment.