About
I didn't learn AI from a course: I have LLMs in production.
I'm Andrés Santana, Rulo. By day I build Ternium's multi-agent conversational assistant from Arkano. By night I build Hermes OS, my own Jarvis. Six years making software survive real users, now with generative AI too.
Bogotá, Colombia · remote since 2020
Spanish (Native)
English (Professional)
My story
From writing songs to putting language models to work.
- BEFORE CODE
Music was the plan.
I wrote songs and that was the life plan, until technology transformed the industry and forced me to choose between what I loved and what let me make a living. I chose to survive, and learned to code from scratch. - 2019
Learning for real, getting paid for it.
A year at Platzi studying frontend development and, alongside it, projects for startups and SMBs: from a Figma design to production, with React and Next.js. - 2020 — 2026
Six years making software survive real users.
From frontend to senior at Vitau, a digital pharmacy in Mexico. I took LCP from 5.8s to 2.5s and CLS from 0.3 to 0.1, the modular checkout I architected cut cart abandonment 31% ($2.8M a year), and daily active users rose 23% to over 450,000. Mentored three juniors, two promoted. - TODAY · BY DAY
Ternium's multi-agent assistant, from Arkano.
Frontend and full-stack BFF of a global steel manufacturer's conversational assistant: one agent per operational area — production, safety, meeting minutes — on a FastAPI and LangGraph backend. Real-time chat with streaming and voice mode on Azure OpenAI and the Vercel AI SDK, SSO with Entra ID and step-up MFA, and an OWASP audit with 20 findings, 15 of which I remediated. - TODAY · BY NIGHT
Hermes OS, my own Jarvis.
An end-to-end agent system running 24/7: multi-agent orchestration with tool calling and permission guardrails, RAG with pgvector across five sources, voice in and out, a meeting copilot at ~2s latency and gesture control. Not a demo: my production lab.
My rule: every visible number is real. Each metric on this site is backed by a commit, a dashboard or a report.
I direct coding agents (Claude Code and the Agent SDK) under guardrails: I own the architecture and system design, they do the typing. Off-screen, a musician. That's where “Más allá del código” was born.
Services
How I can help
I build on language models and make the part users touch as solid as the model behind it.
Product on top of LLMs
Chat interfaces with streaming, voice mode, multi-agent orchestration, RAG and tool calling with permission guardrails. Azure OpenAI, Anthropic Claude, LangGraph, Vercel AI SDK and MCP, with evals so you know it actually works.Multi-agent
RAG and pgvector
Streaming and voice
LangGraph
MCP
Frontend that survives production
Next.js App Router, React 19 and TypeScript with the boring part solved: Core Web Vitals, accessibility, testing with Jest, RTL and Playwright, OWASP security and real observability.Next.js
React 19
TypeScript
Core Web Vitals
OWASP
AI training for non-technical professionals
The AI Shift Challenge: 4 live weeks, 4 private and 2 group sessions, to leave with a daily copilot and an automation of your own running. No code.AI Shift Challenge
AI copilot
No code
Experience
Arkano Software
2026 - Present- Frontend and full-stack BFF of Ternium's multi-agent conversational assistant, a global steel manufacturer: one agent per operational area on a FastAPI + LangGraph backend.
- Real-time chat with streaming (SSE/WebSockets) and voice mode on Next.js App Router, React 19 and the Vercel AI SDK against Azure OpenAI.
- OWASP audit of the BFF layer: 20 findings prioritized, 15 remediated in code — Zod validation, CSP, per-user rate limiting on Redis with atomic Lua.
- End-to-end observability with Application Insights: the first real adoption data the product team ever had.
- Corporate SSO with Microsoft Entra ID (OAuth/OIDC) on Better Auth, with step-up MFA, and i18n in Spanish, English and Portuguese.
AI Shift Challenge · rulocode
2026 - Present- A 4-week live program for non-technical professionals: 4 private sessions, 2 group sessions and an automation of their own running at the end.
- A study platform of my own (Next.js + Supabase) with a free Week 0, lessons and progress tracking.
CareWays Collaborative
2026- A platform to reduce pediatric ICU mortality across Latin America: clinical education and analytics modules, end to end.
- Clinical-outcome dashboards with Recharts, role-based permissions (RBAC) and clinical forms with react-hook-form and Zod.
Vitau
2020 - 2026- Modular checkout that cut cart abandonment 31%, worth $2.8M a year.
- Performance work that lifted daily active users 23%, past 450,000. LCP from 5.8s to 2.5s and CLS from 0.3 to 0.1.
- Next.js 15 migration: −40% bundle and −50% build time. TypeScript standards adopted company-wide.
- Tonder payment gateway integration processing $500K+ monthly, and n8n automations that cut manual scheduling 80%.
- Technical mentoring for three juniors, two promoted, on an eight-person cross-functional team.
Freelance
2019 - Present- 10+ projects for startups and SMBs across e-commerce, SaaS and real estate.
- End-to-end web platforms, from Figma designs to production on Vercel.
Achievements
3rd place — Primera Hackatón Samatech
Santa Marta, Colombia · 2026
Studies
Platzi
Software development, frontend (2019 - 2020).Google & MinTic
Cybersecurity.Continuous learning
Anthropic, OpenAI and Vercel docs and courses. I build with every new model before recommending it.Stack
What I work with
What I use every day, in production.
AI in production
Azure OpenAI
Anthropic Claude
LangGraph
Vercel AI SDK
Claude Agent SDK
MCP
RAG and pgvector
Evals
Prompt and context engineering
Frontend
Next.js (App Router)
React 19
TypeScript
Tailwind CSS
Radix
Zustand
React Query
GraphQL
Jest · RTL · Playwright
Platform
PostgreSQL and Drizzle
Redis
Azure and Cosmos DB
Docker and Kubernetes (AKS)
Application Insights
Better Auth and Entra ID
CI/CD
Vercel