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Lima, Peru · Full stack + AI

Full stack developer & applied AI engineer

I build business systems — ERP, sales management and e-invoicing — and make them intelligent: agents, RAG search and voice assistants already running in production.

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About me

I understand the business and turn it into software that thinks.

Paul Yoel Antezana Yana

Lima, Perú

For 7+ years I have been building systems for companies: ERP, sales management and electronic invoicing, with C# .NET, React, SQL Server, PostgreSQL, Python and PHP.

Since 2024 I have been bringing artificial intelligence into a production ERP: assistants and agents that operate the system, search over company data (RAG), file analysis and voice mode, combining cloud and local models.

I know the day-to-day behind the code — inventory, logistics and accounting basics — so I design solutions people actually use. I hold a bachelor’s degree in Systems Engineering.

  • 7+years building business systems
  • 30+systems and websites delivered
  • 2024AI in production inside an ERP
  • 3languages: Quechua, Spanish and English

What I do

From data to agent, end to end.

I design, build and maintain complete systems: database, API, interface and the AI layer that makes them more useful.

01

Applied AI

Assistants and agents that run real operations with function calling and MCP, RAG search over company data, document analysis and voice mode.

OpenAIClaudeGeminiOllamaLangChainLangGraphMCP
02

Business systems

Custom ERP, CRM and MRP: inventory, logistics, sales, purchasing and SUNAT e-invoicing, with management reporting.

C# .NETSQL ServerPostgreSQLPower BI
03

Full stack development

Solid REST APIs and fast web apps (SPA and PWA), designed to grow and be maintained for years.

ReactTypeScriptVue.jsAstroPythonLaravelNode.jsGo
04

Automation

Bots and automated workflows with n8n and Make; WhatsApp, Messenger and Instagram integration through the official Meta API.

n8nMakeWhatsApp Business APIMeta API

Journey

From Cusco to AI in production.

More than a decade building software: teaching, dozens of business systems, my own SaaS and today AI agents inside an ERP.

  1. 2024 — present

    PCH · Full Stack & AI Developer

    Lima

    AI assistant built into the ERP that runs operations through agents; RAG, file analysis and voice mode. Inventory, logistics, sales, CRM and MRP modules.

  2. 2023 — present

    Yarbys · Founder & developer

    Own venture

    Multi-tenant business management SaaS with e-invoicing and Meta integrations. Goes into production in late November 2026.

  3. 2021 — 2024

    ENPROYEC · Systems Analyst

    Lima

    Back end and front end of an ERP with C# .NET (REST API) and React (SPA, PWA). Data analysis and reporting with SQL Server and Power BI.

  4. 2019 — 2021

    SKYNET · Full Stack Developer

    Cusco

    12+ systems for sales, transport, NGOs, education, restaurants and hotels, with payment gateways and invoicing.

  5. 2016 — present

    Freelance · Developer

    In parallel

    Where I started as a developer: 20+ websites, Sedna (my UI library), bots, automations and AI assistants for businesses.

  6. 2014 — 2018

    Early years · Development, support and teaching

    Cusco

    Reinco mobile app in Xamarin (Code Perú), web platforms, InDesign automation and teaching Office, design and advanced Excel.

Projects

Software that works every day.

A selection of what I have built: from AI agents in an ERP to my own SaaS.

Agent-based assistant · PCH

ERP + IA

An assistant inside the ERP that understands what you ask and does it: runs operations with function calling, searches company data with RAG and can be used by voice.

Function callingMCPLangGraphRAGOllama

Multi-tenant SaaS · Since 2023

Yarbys

Business management system: sales, purchasing, inventory, cash register and e-invoicing, integrated with WhatsApp, Messenger and Instagram. Goes into production in late November 2026.

SaaSFacturación SUNATMeta API

Business automation

Bots & flujos

Automated bots and workflows with n8n and Make connected to CRMs and messaging channels, plus AI assistants for support and sales.

n8nMakeWhatsApp APIChatbots

Custom software · SKYNET

12+ sistemas

Systems for sales, transport, NGOs, education, restaurants and hotels, with payment gateways and e-invoicing.

ASP.NETPHPVue.jsReact

Open source

Open code on GitHub.

A selection of my 77 public repositories: AI assistants, games, UI libraries and learning projects.

See everything on GitHub
tutoriales

JARVIS — asistente con IA

Personal assistant that knows your data (RAG), remembers every conversation and answers by voice in the browser.

RAGLangChainOllamaQdrantFastAPI
PythonUpdated 2026
country_game

Batalla de Comida

Interactive TikTok LIVE game: chat picks a country, and likes, gifts and follows attack or heal its signature dish.

PhaserSocket.IOExpressTikTok LIVE
JavaScriptUpdated 2026
dnui

dnui

Monorepo for a UI component library: TypeScript core, React package, documentation site and demo.

TypeScriptReactTailwindpnpm
TypeScriptUpdated 2026
Sedna

Sedna UI

My SCSS and JavaScript component library for responsive, mobile-first websites, published on npm.

SCSSJavaScriptnpm
JavaScriptUpdated 2025
youtube

PHP desde cero

An MVC, an ORM and a router written in plain PHP, no frameworks, to understand how they work inside.

PHPMVCORMRouter
PHP61Updated 2023
Dashboard

Dashboard WinForms

Modern desktop dashboard in C# with .NET Framework and Bunifu UI, a base for management apps.

C#.NETWinForms
C#34Updated 2019

Laboratory

Games and experiments built with AI

A place to try ideas: prototypes, games and demos I build together with AI models. Some are serious, some are just for fun.

All experiments
Game

Qhapaq Ñan

Run like a chasqui along the Inca Trail in 3D, from the coast to Machu Picchu. Dodge obstacles, jump gorges, cross rope bridges and learn Quechua words. Play with the keyboard or with head movements using your camera (AI in your browser).

three.jsMediaPipeWeb AudioQuechua

Contact

Shall we build something smart together?

Custom systems, AI assistants for your company or automations that save hours. Write to me and let’s talk.

[email protected]View my résumé