Senior Full Stack Developer – Agentic AI (Temporary)

At EX Squared LATAM, we are a digital transformation company focused on building innovative, high-impact technology solutions that drive real business value. We partner with top-tier clients across global, regional, and local markets, fostering a collaborative, inclusive, and innovation-driven culture where your ideas truly matter. Role Overview We’re currently looking for a Senior Full Stack Developer with strong experience in React, Node.js, TypeScript, and agentic AI workflows. You’ll help our client build and maintain a catalog of AI agents designed to support the software development lifecycle, including code generation, quality assurance, product management, design-to-code, and content-authoring workflows. This position combines full-stack engineering with prompt engineering, agent development, evaluation, observability, and continuous experimentation. The ideal candidate is a collaborative and proactive engineer who can explore emerging AI technologies, turn ideas into practical solutions, gather feedback from delivery teams, and continuously improve agent performance. Location: Fully remote position within LATAM. Contract Duration: 6-month fixed-term contract with possibilities of extension. Language Requirement: Advanced English. What you'll do - Build and maintain AI agents supporting software development, QA, and product teams. - Develop code-generation, coding-standard, design-to-code, and workflow automation agents. - Design structured, dependency-aware agentic workflows rather than single-prompt solutions. - Create agent skills, prompts, tool interfaces, and reusable workflow components. - Implement evaluation and observability practices to monitor agent quality and performance. - Develop self-validation and error-recovery loops using testing and type-checking results. - Build and maintain applications using React, Node.js, and TypeScript. - Develop and consume REST and GraphQL APIs using established best practices. - Integrate agents with internal systems, SaaS platforms, APIs, and development tools. - Collaborate with delivery teams, collect feedback, and improve existing agent solutions. - Research emerging AI tools, frameworks, vendors, and local model alternatives. - Document agent behavior, architecture decisions, limitations, and usage guidelines. - Apply security, accessibility, testing, and performance standards throughout development. - Participate actively in team discussions, technical planning, and solution design. What you'll bring - 5+ years of professional full-stack development experience. - Strong hands-on experience with React, Node.js, and TypeScript. - Experience building, integrating, or maintaining agents and agentic workflows. - Knowledge of prompt engineering, task decomposition, context management, and tool calling. - Understanding of agent evaluation, observability, validation, and error-recovery patterns. - Experience consuming GraphQL APIs, ideally using Apollo Client. - Experience with REST APIs and third-party SaaS integrations. - Familiarity with AWS, Docker, and cloud-based application architecture. - Experience with automated testing tools such as Jest, Cypress, or Vitest. - Understanding of secure API development, OAuth2/OIDC, API keys, and access controls. - Experience developing accessible interfaces aligned with WCAG 2.1 AA. - Ability to structure clean, scalable, and maintainable application code. - Strong documentation and technical communication skills. - Advanced English and the ability to collaborate in a distributed environment. - A proactive, exploratory mindset with the ability to work independently. - A Mac computer meeting the client’s BYOD requirements, preferably with 32 GB RAM. What will make you stand out - Experience creating agent skills using Markdown-based instructions. - Knowledge of RAG and other retrieval-based AI patterns. - Experience with LLM structured outputs, function calling, or tool calling. - Familiarity with golden test sets, LLM-as-judge, and…