Nacho Viejo

Led multidisciplinary teams of 6–15 engineers responsible for the Listings experience across web, mobile, and backend services. Engineering Manager responsibilities began in August 2022, with the formal title transition in January 2023.

• Led the team through completion of the Listings migration: 100% of production traffic moved to the new application and legacy systems retired in early June against an October plan, maintaining scope and quality. Developed and progressively delegated technical leadership to a Staff Engineer.
• Built the team's capability in event-driven architecture across urgency signals, video processing, and the internal Listings cache. Across the team's caching, compression, routing, and operational improvements, outcomes included 90–99% cache hit rates, approximately 70% less CloudFront egress, and approximately 30% lower daily infrastructure costs.
• Drove engineering strategy with Product, Design, SRE, and Platform partners, balancing product delivery with quality and operational sustainability. Recommended pausing feature work to address a material Listings performance regression; the team restored the LCP baseline.
• Partnered with Product and Analytics to deliver multi-ticket selection, generating approximately 378,000 incremental orders annually.
• Led repeating-event improvements that increased indexed Listings pages by 23%.
• The team's migration more than halved response times, brought Core Web Vitals into green ranges, and strengthened SEO.
• Directed phased and blue-green rollouts for three critical services, including observability, incident response, on-call readiness, resilience, security, performance, and accessibility.
• Owned hiring decisions for my team jointly with HR and helped standardize engineering interview calibration in 2023.
• Developed engineers and engineering managers through regular feedback, performance management, career development, and promotion support, including an Engineer II's promotion to Senior and mentoring Staff Engineers exploring management.
• Individual practice: Returned to hands-on contribution gradually, from bugs to more critical work, to evaluate AI tools, delegation boundaries, and security guardrails firsthand.
• Team adoption: Built and evolved a shared engineering harness, transferred learning from technology events, delivered an introductory workshop on Google's Agent Development Kit, and led an operational-excellence hackathon. The complete agent system remained a partial prototype, but several specialized agents continued supporting weekly data gathering and triage.
• Company governance: Worked with the CTO, VP of Engineering, and a Principal in Security on AI governance design, responsible-use boundaries, and cross-team reuse, continuing until my departure in June 2026.

Provided cross-system technical leadership across Checkout and Listings. The final months overlapped with the transition into Engineering Management.

• Shaped architecture and engineering practices for React, TypeScript, Node.js, testing, experimentation, and distributed systems.
• Led complex customer-facing initiatives across multiple squads, translating product goals into technical direction, delivery plans, and coordinated rollouts.
• Designed quality strategies that expanded scalable end-to-end testing, strengthened delivery guardrails, and supported more autonomous engineering teams.
• Mentored engineers, reviewed technical designs, removed blockers, and balanced immediate delivery with system quality.

• Helped build Eventbrite's unified Checkout experience with React, Redux, TypeScript, Cypress, and modern web engineering practices.
• Introduced early end-to-end testing practices adopted across multiple teams and helped integrate Ticketea's engineers, systems, and delivery practices after its acquisition.