I build complete systems — frontend, backend, database, and infrastructure — and stay on to run them in production. Before writing code, I find out what process is actually costing the business time or money; the technical solution follows from there.
📍 Barquisimeto, Venezuela (remote) · 📫 juancvillefer@gmail.com · 🌐 jevy.dev
- 🧱 End-to-end business systems — e-commerce, SaaS, CRM, healthcare/admin platforms
- 🤖 AI integrated into production pipelines — document processing, conversational agents with function calling
- ⚙️ Process automation with n8n
- 🐳 Infrastructure — Docker, Traefik, Linux, self-hosted deployments
🏥 Invoicing automation — AI pipeline for a healthcare client
Two-step AI pipeline that reads clinic invoices in multiple formats and translates them into the tax schema required by the electronic billing provider. An audit layer validates totals before issuing, and each tax series resolves with its own strategy, so adding a new one doesn't affect the rest.
🔧 Catalog sync — hardware e-commerce store, Madrid
Microservice that keeps stock, price, and availability in sync with an external supplier and publishes them to the store, with a custom pricing engine, capped retries, and AI-generated product descriptions. Runs unattended and reports via Telegram.
💍 KissthePlan — collaborative wedding-planning SaaS (Spain)
Real-time multi-user editing over the same wedding: guests, budget, seating chart, and a public wedding page. Shared access model instead of separate disconnected accounts.
📦 SpaceShare — storage rental marketplace (El Salvador / Panama)
Hexagonal architecture reused as a portable template, Wompi payment integration (card + 3D Secure — the direct-charge flow sends no webhook at all, confirmed debugging in production), and hybrid online/offline repositories. Code: space-share-front.
📊 Audita — multi-tenant SaaS for audit firms (Guatemala)
Role hierarchy across tenants, dynamic document generation (Word/Excel) with business rules, automated backups.
🗓️ Medical appointment system — scheduling platform for doctors
Next.js frontend with a NestJS backend (Clean Architecture).