• Design, build, and maintain LLM-powered solutions including custom GPTs and domain-specific assistants. • Develop and optimize prompts, system instructions, and context strategies for accuracy and reliability. • Implement prompt chaining, tool calling, and basic agentic workflows. • Build and support Retrieval-Augmented Generation (RAG) pipelines using vector databases. • Evaluate, test, and improve LLM outputs using defined quality and safety criteria. • Apply responsible AI principles, safety guardrails, and governance standards in all implementations. • Develop full stack AI-enabled applications including backend services, APIs, and UI integrations. • Integrate LLM capabilities into existing enterprise applications. • Build reusable services and components to support AI features. • Debug and resolve application or AI-related issues impacting functionality or user experience. • Develop and deploy AI solutions on Azure and/or AWS. • Support CI/CD pipelines for application and AI workloads. • Assist with MLOps workflows including model versioning, deployment, and monitoring. • Ensure solutions are secure, reliable, and cost-aware in production environments.

• Build powerful buyer tooling • Lead development of our next-generation buyer platform • Build and optimize the matching engine • Architect for scale: Design and operate microservices and distributed, event-driven systems • Elevate the seller experience: Make it effortless for sellers to understand their options, price their items accurately • Take an AI-first approach to building • Own outcomes end-to-end: Take projects from 0 to 1 • Drive cross-functional execution: Translate strategy into clear technical plans • Connect the ecosystem: Ensure seamless liquidity handoffs across the broader PSA enterprise • Communicate with clarity at every level

WeWork Reforma Latino (97001), Mexico, Ciudad de Mexico, Ciudad de Mexico Senior Software Engineer - Full Stack Do you love building and pioneering in the technology space? Do you enjoy solving complex business problems in a fast-paced, collaborative, inclusive, and iterative delivery environment? At Capital One, you'll be part of a big group of makers, breakers, doers and disruptors, who solve real problems and meet real customer needs. We are seeking Full Stack Software Engineers who are passionate about marrying data with emerging technologies. As a Capital One Senior Software Engineer, you'll have the opportunity to be on the forefront of driving a major transformation within Capital One. What You'll Do: - Collaborate with and across Agile teams to design, develop, test, implement, and support technical solutions in full-stack development tools and technologies - Share your passion for staying on top of tech trends, experimenting with and learning new technologies, participating in internal & external technology communities, mentoring other members of the engineering community - Collaborate with digital product managers, and deliver robust cloud-based solutions that drive powerful experiences to help millions of Americans achieve financial empowerment - Utilize programming languages like JavaScript, Java, HTML/CSS, TypeScript, SQL, Python, and Go, Open Source RDBMS and NoSQL databases, Container Orchestration services including Docker and Kubernetes, and a variety of AWS tools and services Basic Qualifications: - Bachelor's Degree - Advanced Level of English - At least 3 years of experience in software engineering (Internship experience does not apply) Preferred Qualifications: - At least 3+ years of experience in at least one of the following: JavaScript, Java, TypeScript, SQL, Python, or Go - At least 3+ year of experience with AWS, GCP, Microsoft Azure, or another cloud service - At least 3+ years of experience in open source frameworks - At least 3+ years of experience in Agile practices At Capital One, we respect individual differences in culture, religion, and ethnicity. Likewise, we promote equal opportunities and development for all personnel. In the hiring process, we seek to provide equal employment opportunities to candidates, regardless of race, color, religion, gender, sexual orientation, marital or civil status, national origin, disability, or any other situation protected by federal, state, or local laws. For technical support or questions about Capital One's recruiting process, please send an email to Careers@capitalone.com Capital One does not provide, endorse nor guarantee and is not liable for third-party products, services, educational tools or other information available through this site. Capital One Financial is made up of several different entities. Please note that any position posted in Canada is for Capital One Canada, any position posted in the United Kingdom is for Capital One Europe, any position posted in the Philippines is for Capital One Service Corp (COPSSC), and any position posted in Mexico is for Capital One Technology Labs Mexico.

• Own and contribute to architecture and development across products, driving technical excellence in both frontend and backend systems. • Develop and optimize backend API services with test-driven development including advanced caching and messaging for reliability and scalability. • Deliver high-quality frontend experiences using modern frameworks, with strong fundamentals in component-based architectures and state management. • Integrate and support observability, logging, and monitoring to ensure platform reliability and rapid incident response. • Ensure top-tier application security and compliance, applying best practices across frontend, backend, and API layers (authentication, authorization, rate-limiting, OWASP). • Leverage LLMs and AI tools to write, refactor, test, and debug code efficiently, implementing guardrails for reliability. • Participate in design reviews, deep dives, and on-call rotations to support a culture of accountability and operational excellence.