Senior Fullstack Engineer

About us

Xpend Marketing builds advanced marketing solutions that help brands scale fast. We work with leading companies in high-performance industries, supporting their growth across the entire funnel - from acquisition to retention. Our team specializes in performance marketing, paid social, and large-scale campaign management, operating across global markets and high budgets.

With a strong focus on data, speed, and continuous optimization, we enable our partners to launch, test, and scale campaigns that drive real results.

We are looking for a Senior Fullstack Engineer with deep expertise in React\NodeJs to lead the architecture, performance, and quality of our fullstack systems. This role is highly hands-on and focuses on building, optimizing, and scaling complex saas applications across devices and browsers. You will own fullstack technical standards, lead architectural decisions, and play a key role in hands-on development, code reviews. A strong experience with AI-driven development is mandatory.

Key Responsibilities

• Own and lead the fullstack architecture for complex, large-scale web applications
• Be hands-on with React\NodeJS, setting high standards for code quality and maintainability.
• Drive client and backend side performance optimization, including rendering, state management, and runtime efficiency.
• Ensure excellent user experience across multiple browsers, screen sizes, and devices (desktop, tablet and mostly mobile).
• Collaborate closely with product, design design teams
• Lead and integrate AI-based development workflows and features (Cursor, Claude and Agents).

Requirements

• 6+ years of experience in fullstack development
• Hands-on experience in AI-based development - mandatory
• Proven experience optimizing performance of complex applications (render cycles, memoization, virtualization, backend, databases)

Nice to have

• Experience with frameworks such as Next.js/NestJS
• Familiarity with design systems and component libraries
• Experience with performance monitoring and observability tools

What We Offer

• A senior technical leadership role with strong influence on frontend architecture
• Ownership of performance, quality, and scalability of client systems
• Opportunity to work with cutting-edge AI-driven development workflows
• Collaboration with strong product, design, and engineering teams
• Competitive compensation and benefits