# Cesar William Alvarenga

> Technical Lead, AI at Arena — building intelligent products with LLMs, AI agents, and real-time experiences. Based in San Jose, California, with 18+ years of software engineering experience.

Personal site of Cesar William Alvarenga. The pages below are the complete set of canonical URLs on this domain.

Every content page is also served as markdown: append `.md` to the URL (the home page is at /index.md), or request the page URL with `Accept: text/markdown`. Those URLs are listed under Markdown below.

## Pages

- [Home](https://cesarwilliam.com/): Cesar Alvarenga — Technical Lead, AI at Arena. Current projects, recent writing, and what he is building with LLMs and agents.
- [About](https://cesarwilliam.com/about): Full background: 18+ years of engineering, the move from front-end architecture into AI leadership, career timeline, skills, and education.
- [Uses](https://cesarwilliam.com/uses): The hardware, editor setup, and tools Cesar uses day to day for AI product development.

## Projects

- [Olympic Games Paris 2024 (Chrome extension)](https://cesarwilliam.com/olympic-games-paris-2024): Landing page for the Olympic Games Paris 2024 Chrome extension — real-time medals, videos, highlights, and fan chat.
- [World Cup 2026](https://cesarwilliam.com/worldcup): Companion site for the World Cup 2026, served from this domain via Next.js Multi-Zones. Listed in full below.

## World Cup 2026

- [World Cup 2026](https://cesarwilliam.com/worldcup): Companion site for the World Cup 2026 — live scores, AI predictions, schedule, and standings across 5 languages.
- [Live Scores](https://cesarwilliam.com/worldcup/live-scores): Real-time World Cup 2026 match scores.
- [Schedule](https://cesarwilliam.com/worldcup/schedule): Full World Cup 2026 match schedule.
- [Predictions](https://cesarwilliam.com/worldcup/predictions): AI-generated match predictions.
- [Standings](https://cesarwilliam.com/worldcup/standings): Group and tournament standings.
- [Stats](https://cesarwilliam.com/worldcup/stats): Player and team statistics.
- [News](https://cesarwilliam.com/worldcup/news): World Cup 2026 news coverage.
- [Blog](https://cesarwilliam.com/worldcup/blog): Long-form World Cup 2026 articles.
- [Tickets](https://cesarwilliam.com/worldcup/tickets): World Cup 2026 ticket information.

Localized under /worldcup/{es,pt,fr,ar}/… — the complete set of URLs, including every locale, is at https://cesarwilliam.com/worldcup/sitemap.xml.

## Markdown

- [Home (markdown)](https://cesarwilliam.com/index.md): Cesar Alvarenga — Technical Lead, AI at Arena. Current projects, recent writing, and what he is building with LLMs and agents.
- [About (markdown)](https://cesarwilliam.com/about.md): Full background: 18+ years of engineering, the move from front-end architecture into AI leadership, career timeline, skills, and education.
- [Uses (markdown)](https://cesarwilliam.com/uses.md): The hardware, editor setup, and tools Cesar uses day to day for AI product development.
- [Olympic Games Paris 2024 (Chrome extension) (markdown)](https://cesarwilliam.com/olympic-games-paris-2024.md): Landing page for the Olympic Games Paris 2024 Chrome extension — real-time medals, videos, highlights, and fan chat.

## Elsewhere

- [My Avatar](https://myavatar.ai): AI platform built at Arena for creating digital avatars with text, voice, and video conversations.
- [AI Concierge](https://arenachat.com): AI-powered customer engagement assistant for Arena.
- [NFL Live Hub](https://nfllivehub.com): Chrome extension for real-time NFL scores, stats, and fan chat.
- [react-input-emoji](https://www.npmjs.com/package/react-input-emoji): Open-source React input component with an emoji picker; millions of npm downloads.
- [GitHub](https://github.com/cesarwbr): Open-source repositories.
- [LinkedIn](https://www.linkedin.com/in/cesarwalvarenga): Professional profile and work history.
- [X](https://x.com/cesarwbr): Short-form posts.
- [Medium](https://medium.com/@cesarwilliam): Long-form articles — the source of the posts listed on the home page.
- [Dev.to](https://dev.to/cesarwbr): Developer-focused articles.

## Optional

- [Full site brief](https://cesarwilliam.com/llms-full.txt): Longer prose version of this file: bio, current work, expertise, career timeline, and FAQ.
- [Sitemap](https://cesarwilliam.com/sitemap.xml): XML sitemap for the main site.
- [Privacy Policy](https://cesarwilliam.com/privacy): Privacy policy for cesarwilliam.com and its extensions.
- [Terms of Service](https://cesarwilliam.com/terms-of-service): Terms of service for cesarwilliam.com and its extensions.
- [Legal AI Privacy Policy](https://cesarwilliam.com/legal-ai-privacy-policy): Privacy policy covering the Legal AI project.