Senior Full-Stack Developer at Vast LLC – San Juan, Puerto Rico

ABOUT VAST

Vast builds the operating and financial backbone for fast-growing, cash-intensive businesses, combining hands-on execution with purpose-built software, automation, and AI-enabled workflows.

We provide technology-enabled shared services, financial infrastructure, and operational support to partners across the U.S. and Puerto Rico, with deep roots in route gaming and other multi-location businesses. Our teams work directly inside the operations—handling real cash flows, real data, and real constraints—while designing systems that make the business faster and easier to scale.

We focus on execution first: accurate books, strong controls, and dependable processes. From there, we build automation, software, and AI-enabled workflows that eliminate manual work and raise the standard for how the back office operates. This is a hybrid role, with three days each week expected to be onsite at our Chicago, IL office.

YOUR MISSION

As our Senior Developer, you’ll be one of the founding members of our engineering team. You’ll collaborate directly with leadership to build beautiful, performant, and reliable interfaces from the ground up.

We’re looking for someone who thrives in ambiguity, loves to iterate quickly, and is excited by the opportunity to make foundational technical decisions, utilizing AI and other technologies to create immediate business value.

WHAT YOU’LL DO

• System Architecture & Design: Define and evolve our technical architecture across the stack—frontend, backend, APIs, data, and cloud infrastructure.
• Technical Leadership: Set coding standards, architectural patterns, and best practices for engineering teams.
• Scalability & Performance: Ensure our systems are built to handle growth efficiently and reliably.
• Hands-On Development: Lead by example with high-quality code contributions across the stack.
• Cross-Functional Collaboration: Work closely with Product, Design & Business Stakeholders to align on technical vision and deliver seamless experiences.
• Code Reviews & Mentorship: Uplevel the engineering team through mentorship, knowledge sharing, and thoughtful reviews.
• Technology Evaluation: Research and recommend new tools, frameworks, and practices to stay ahead of the curve.

• 5+ years of experience in full-stack development, with 2+ years in a start-up environment.
• Deep experience in both front-end and back-end frameworks (e.g., Vue, TypeScript, Tailwind, and Laravel/PHP, etc.).
• Strong knowledge of cloud infrastructure (AWS, Forge, or Azure) and DevOps best practices.
• Proven track record designing scalable, secure, and maintainable systems.
• Ability to balance hands-on engineering with high-level architectural strategy.
• Excellent communication skills and a collaborative mindset.

WHY JOIN VAST?

• Competitive salary + performance bonuses
• Work with a fast-growing, tech-forward company
• Direct impact on go-to-market success and company growth