Loading profile…
Williams Mejias
Looking for a jobFreelance Full-Stack Developer
Full-Stack Engineer building React and TypeScript apps, including FitScore's Firebase backend and payments integrations.
VenezuelaFreelance Full-Stack Developer at Self Employed
Experience
Freelance Full-Stack Developer
Developed multiple freelance projects including a TypeScript monorepo with PostgreSQL/Prisma, a Fastify API, and Next.js apps; a backend on Cloud Functions with Express and a React Native app; and a backend on Firebase Cloud Functions with Stripe/PayPal and SendGrid integrations.
TypeScriptPostgreSQLPrismaFastifyExpressNext.jsDockerCloud FunctionsReactViteReact NativeExpoFirebaseFirestoreStripePayPalSendgridJestFirebase Emulator Suite
Senior Frontend Developer
Built and maintained production features in React and TypeScript for a logistics client, using Ant Design/MUI and drag-and-drop interfaces. Applied AI agents and spec-driven development to support codebase analysis, implementation and test development.
ReactTypeScriptAnt DesignMUIPlaywrightCypressJiraConfluenceAI AgentsSpec Driven Development
Frontend Developer
Developed React and React Native applications in TypeScript, with Ionic for cross-platform delivery. Integrated GraphQL APIs and built forms with Zod and React Hook Form, styled with Tailwind.
ReactReact NativeTypeScriptIonicGraphQLZodReact Hook FormTailwindCypressPlaywright
Frontend Developer
Delivered React, React Native and Ionic applications in TypeScript over five years. Integrated GraphQL services and built Shopify/Liquid storefront functionality.
ReactReact NativeIonicTypeScriptGraphQLShopifyLiquidCypressPlaywright
Education
Universidad Alejandro de Humboldt
Earned a degree in Computer Engineering from Universidad Alejandro de Humboldt in 2016.
Earned a degree in Computer Engineering from Universidad Alejandro de Humboldt in 2016.
Harvard University
Completed HarvardX CS50 AI with Python, covering artificial intelligence concepts and applications.
AI Engineer Core Track
Completed the AI Engineer Core Track, focusing on LLM Engineering, RAG, QLoRA, and agents.