Johan Sebastian V.

I build practical data, AI, and automation solutions that help businesses save time, improve reporting, and turn ideas into working products. I'm a Senior Data & AI Engineer with 12+ years of experience across business intelligence, data engineering, and cloud platforms. I also develop web applications, AI assistants, and integrations, from requirements and architecture through testing and deployment. HOW I CAN HELP • Power BI dashboards: fix DAX, Power Query, refresh issues, semantic models, or build KPI reports from SQL, Excel, CSV and business systems. • Data engineering: SQL/Python ETL and ELT, API pipelines, Snowflake, BigQuery, Redshift, dbt, Airflow and Microsoft Fabric. • AI agents and automation: website assistants, LLM integrations, knowledge assistants (RAG), lead capture, human handoff and booking workflows. • n8n and APIs: connect business tools, automate data movement and build error-handled workflows. • Web apps and backends: React, TypeScript, Cloudflare Workers, D1, REST APIs, admin panels, forms and deployment. • Focused fixes: debug existing dashboards, workflows, APIs and web applications with a clear scope and testable result. PROJECT EXAMPLES Velai — With my team, I worked on the architecture, integrations and React administration of a multitenant AI assistant platform supporting web and WhatsApp conversations, lead workflows and reservations. PUENTE — I directed and developed a community-focused web application pilot with React, TypeScript, Cloudflare Workers/D1, user accounts, listings, permissions, chat and AI-supported features. HireDataVision — I helped build a data engineering and BI consulting website integrated with a branded AI assistant. NAYA Eventos — I developed and integrated event booking workflows including persistent requests, consent records and backend connections. ENTERPRISE EXPERIENCE I have contributed to data and BI initiatives for Iberia, Mango, Iturri, AB InBev and Ecopetrol involving cloud analytics, SQL models, ETL/ELT, orchestration and reporting. Client data and systems remain confidential. WHY WORK WITH ME? • Top Rated Plus on Upwork with $40K+ in historical earnings. • Hands-on experience in both enterprise data platforms and real web and AI products. • Available for well-defined small fixes and larger milestone-based projects. • Native Spanish and conversational English (B2), based in Spain. Tell me your system, the problem and the expected result. I can propose clear deliverables, scope and a practical validation plan.