# Erick Xavier **Tech Lead | Frontend Architect | Open-Source Framework Creator** hire@exs.dev | +55 21 97227-7224 | Brazil (GMT-3) [linkedin.com/in/exs](https://linkedin.com/in/exs) | [exs.dev](https://exs.dev) | [no-js.dev](https://no-js.dev) Brazilian & Portuguese Citizen | EU Passport Holder Eligible to work throughout the European Union without sponsorship --- ## Selected Achievements - 20+ years building web platforms, SaaS products, and developer tooling - Sole creator of No-JS.dev: a complete frontend framework ecosystem with 142 directives, 17 UI element plugins, a VS Code language server (LSP), and an AI skill integration - Reduced frontend regression rates by 65% through Playwright adoption - Helped evolve release cadence from monthly to weekly - Built platforms serving millions of telecom users - Led engineering initiatives across Brazil, New York, and Rome - Operates AI agent teams under strict quality gates: nothing ships without tests, validations, and line-by-line code review --- ## Professional Summary Frontend Architect with 20+ years of experience building SaaS products, developer platforms, and large-scale web applications. Creator of No-JS.dev, an HTML-first reactive framework with 142 directives, a companion UI library (17 element plugins), a VS Code language server, and a growing open-source community, all built solo. Uses AI and LLMs as engineering tools, not as a field of study, operating a team of AI agents and custom skills under strict quality and security parameters, with multiple verification rounds and performance-focused iterations. Every line of generated code is reviewed before deployment, ensuring the delivered software is reliable and efficient. Experienced in Angular ecosystems, frontend architecture, testing strategy, distributed teams, and product development across startups, consulting environments, and international software companies. --- ## Open Source & AI Projects ### No-JS.dev - HTML-First Reactive Framework **Creator | Architect | Maintainer** Website: https://no-js.dev/ Sole creator of a complete frontend framework ecosystem, from core engine to UI library to developer tooling, built around the conviction that the browser is already capable. **Core Framework (142 directives):** - Declarative HTTP (get, post, put, patch, delete), reactive binding, conditionals, loops, state management, SPA routing with guards and nested routes, built-in i18n with pluralization, animations, 32 built-in filters, head/SEO management, DevTools - Zero JavaScript authoring, zero build process, zero dependencies. A single CDN script tag **Ecosystem (all solo-built):** - **NoJS-Elements:** 17 UI element plugins (Drag & Drop, Modal, Tabs, Virtual List, Sortable Table, Form Validation, and more) - **NoJS-LSP:** VS Code language server with autocomplete, hover docs, and diagnostics - **NoJS-Skill:** Claude Code skill for guided project generation - **Test suite:** 120 unit tests + 27 Playwright E2E tests, CI via GitHub Actions **Community:** 75 GitHub stars · 5 forks · npm + jsDelivr CDN distribution · multilingual docs (EN/ES/PT/IT/FR) · Discord community ### AI-Augmented Development Workflow Uses AI and LLMs as engineering tools to accelerate frontend development, not as a field of study or research. Operates a team of AI agents and custom skills built with strict quality and security parameters: - **Tools:** Claude Code, Cursor, Codex, OpenCode, Ollama - **Workflow:** Multi-agent orchestration with custom skills for code review, testing, architecture analysis, documentation, and implementation guidance - **Quality gates:** Multiple verification iterations focused on performance. Nothing is deployed without a full suite of tests, validations, and manual line-by-line code review - **Scope:** Developer productivity tooling, sprint planning assistance, QA workflows. Always as tools in service of software engineering, never as standalone AI/ML development --- ## Professional Experience ### Creator & Developer **No-JS.dev** | Self-employed | Remote | 2025 - Present - Designed and solo-shipped a complete frontend framework ecosystem (core engine, 17-plugin UI library, VS Code language server, AI skill), the kind of surface area typically maintained by dedicated framework teams - Architected a Proxy-based reactive engine with a sandboxed expression evaluator (no eval, CSP-compliant by design), enabling full SPA capabilities through HTML attributes alone - Built a full Language Server Protocol implementation with intelligent completions, diagnostics, and hover docs for a novel HTML directive grammar - Grew the project to 75 GitHub stars and 3,400+ npm downloads across 19 releases and 557 commits, with multilingual documentation in 5 languages Technologies: JavaScript, HTML, CSS, Node.js, Playwright, VS Code Extension API ### Senior Frontend Developer **Data Virtuality / CData Software** | Remote | 2020 - 2025 - Architected the frontend platform through a period of >40% YoY company growth, culminating in a $350M raise at $800M+ valuation - Established reactive patterns with Angular Signals and RxJS that became development standards - Built comprehensive Playwright E2E testing infrastructure - Reduced regression rates by 65% - Supported the transition from monthly releases to weekly releases - Led frontend evolution across multiple product generations - Frontend platform adopted across a 350+ connector data integration product serving enterprise customers including Salesforce and Credit Agricole - Integrated AI tools into planning, implementation, and code review processes Technologies: Angular, Angular Signals, RxJS, NgRx, Playwright, TypeScript ### Frontend Developer (Consultant) **Zydax Consulting** | Rio de Janeiro, Brazil | 2019 - 2020 - Delivered the supplier portal for Drogaria Venancio, a top-10 Brazilian pharmacy chain (R$1B+ revenue, 80+ stores) - Built Angular frontends integrated with Node.js and .NET systems - Led adoption of Flutter for cross-platform mobile development Technologies: Angular, Node.js, .NET, Flutter ### Frontend Developer **Mobicare** | Rio de Janeiro, Brazil | 2018 - 2019 - Built high-volume consent portals for Oi and Claro, operators with a combined base of 100M+ mobile subscribers - Implemented AWS Lambda serverless services - Modernized legacy telecom integrations - Optimized performance for mobile-first consumers Technologies: AWS Lambda ### Frontend Developer (Consultant) **United States Clients** | Remote | 2016 - 2017 - Delivered AngularJS applications for U.S.-based clients - Managed complete project lifecycles independently Technologies: AngularJS ### Team Lead - Frontend & Unity3D Developer **Acotel** | Rio de Janeiro | New York City | Rome | 2013 - 2016 - Led cross-functional teams at a publicly traded company (Borsa Italiana) with subsidiaries across 8+ countries - Coordinated delivery across three continents for products reaching 130M+ potential users via telecom partnerships - Guided adoption of Unity3D for browser and mobile products - Aligned technical execution with business objectives Technologies: Unity3D ### Early Experience **Multiple Agencies** | Rio de Janeiro, Brazil | 2005 - 2013 Organizations: Personare, WeShow, Agencia Azul, Simples, IDEIAS.org.br - Developed web platforms and CMS solutions - Built PHP/MySQL backends and frontend systems - Led end-to-end delivery of tourism and content platforms - Worked across UX, frontend, backend, and deployment activities Technologies: PHP, MySQL --- ## Technical Skills **AI-Augmented Development:** Claude Code, Cursor, Codex, OpenCode, Ollama, AI Agent Orchestration & Custom Skills, Quality-Gated Multi-Agent Workflows **Frontend Architecture:** Angular, Angular Signals, RxJS & NgRx, TypeScript & JavaScript (ES6+), HTML5, CSS3, SASS & LESS, Reactive Framework Design (No-JS.dev) **Testing & Quality:** Playwright (E2E Testing Infrastructure), Jest & Unit Testing Automation, Regression Rate Optimization **Cloud & Backend:** AWS (Lambda, EC2, S3), Node.js, PHP & MySQL **Platforms & Tooling:** Git, Figma & Angular Material, Bootstrap, Flutter & Unity3D **Engineering Practices:** Agile & Scrum Methodologies, Distributed Team Leadership, Technical Leadership & Mentoring --- ## Languages - Portuguese: Native - English: Full Professional Proficiency --- ## Education **Bachelor of Technology in Information Technology** Universidade Veiga de Almeida (2002-2005)