
César Pedro Zea Gomez
Verified Expert in Engineering
Full-stack SQL Developer
Lisbon, Portugal
Toptal member since November 16, 2020
César is a principal data and AI architect with 34 years of experience in software, the last 5 of which he's led production AI for enterprise clients. At Celestial Systems, he built a data and AI practice from 0 to 25 engineers on 4 continents, delivering production AI on Azure OpenAI, Anthropic, MS Fabric, Snowflake, and Dataiku. César is an SQL Server expert with 20+ years of experience in large transactional and BI systems. He's a senior technical authority with full delivery accountability.
Portfolio
Experience
- Microsoft SQL Server - 20 years
- Solution Architecture - 20 years
- Technical Leadership - 20 years
- Python - 5 years
- Machine Learning - 5 years
- Artificial Intelligence (AI) - 5 years
- Generative Artificial Intelligence (GenAI) - 3 years
- Dataiku - 2 years
Preferred Environment
Business Intelligence (BI), Java, Microsoft SQL Server, Artificial Intelligence (AI), Generative Artificial Intelligence (GenAI), Python, Dataiku, Microsoft Fabric, Machine Learning, Snowflake
The most amazing...
...thing was building Celestial Systems' complete data and AI engineering practice from zero, now the core of a 200-engineer consultancy delivering production AI.
Work Experience
Co-founder – Principal Data & AI Architect
Effority
- Founded Effority as an independent consulting and product company, delivering senior data and AI architecture and production AI for enterprise clients.
- Provided principal-level architecture for AI and data programs, including production AI delivery with RAG, agentic systems, and LLM applications.
- Developed a SaaS product on the Anthropic API and other LLM providers, applying agentic AI, prompt engineering, and production LLM architecture.
- Delivered technical due diligence, architecture audits, and trusted technical advisory for high-stakes commercial and engineering situations.
Principal Data & AI Architect
Celestial Systems
- Recognized as the principal architect and technical voice in a 200-engineer consultancy, consulted across high-stakes projects company-wide, and trusted as the architect brought in when engagements had to succeed.
- Built Celestial Systems' Data & AI engineering practice from zero, defining technical vision, organizational structure, delivery model, and the full training curriculum. Now, the core engineering practice of the company.
- Grew the practice to 25 engineers under direct leadership across four continents, designing the full training program and accompanying teams from onboarding through technical formation to production delivery.
- Designed and delivered production AI combining machine learning and generative AI on Azure OpenAI, Anthropic, Microsoft Fabric, Snowflake, and Dataiku for enterprise clients across finance, energy, and pharma.
- Personally signed every Data and AI SOW, ran pre-sales daily with the commercial team, and developed engineers into pre-sales technical authorities to scale the practice's commercial capacity.
- Represented the practice at industry events, including Snowflake Summit 2025 in San Francisco and AI Unveiled in Burnaby, BC, as a featured speaker, often flown in as the technical authority who closed strategic deals.
- Established the Data and AI Center of Excellence, defining standards, certifications, and best practices across the practice, including a full Dataiku certification track for the engineering team.
Founder, CTO, and Principal Software Architect
Jaune Sistemas
- Designed and implemented (for nVent HOFFMAN) a SQL Server and AWS-DMS integration controller and supervisor for a BI DW. It automates all tasks, using AWS-DMS with full automation of BCP and sync processes and a complete Ext JS front end.
- Designed and implemented (for nVent HOFFMAN) a system for the supervision and control of SQL Server ETL processes with time-step evolution analysis, error control, and reporting.
- Implemented most of the remote control system for public lighting and ornamental fountains for the Madrid City Council—a very complex solution that controls 300,000+ lighting points, pumps, and other devices.
- Created a BI portal for the analysis and verification of the compliance indicators for the Madrid remote control lightning and ornamental fountains service.
- Designed and built Iberdrola's system for the sale of shares to employees and a platform to manage flexible compensation for top managers. This global energy leader is no. 303 in the Fortune Global 500, with €36.4 billion in annual revenue (2019).
- Migrated and optimized database servers in the non-stop production environment for ALK-Abello (a pharma company), converting from the old SQL Server version to the new version, with 100% empirical testing of all data and the T-SQL business layer.
- Migrated, optimized, and consolidated database servers in the non-stop production environment for Telepizza, converting the old version that had 12 synchronized SQL Servers to two new SQL Servers, with 100% empirical testing.
- Built several Sencha Ext JS applications for Everis SA and CLH SA, with SAP through REST services in the integrated development system of CLH.
- Developed extensions and modifications for Maxxium España's BI system and data warehouse to support internal business transformation projects.
Founder, CTO, and Software Developer
Jaune Sistemas SL
- Founded this software development company from where I oversaw and developed 100+ software projects with 10 other developers for multinational companies and some small and medium-sized enterprises.
- Built and led development teams for 10 years while also working as a developer and serving customers directly, both from a commercial and technical point of view.
- Implemented a CRM product that was a complete success for 10+ clients. The only problem was its excessive success in relation to the constraints on my capacity to expand the business to ensure its continuity.
- Served as the CIO of Georg Fischer Spain for 5+ years in an outsourced arrangement. Developed internal and B2B management systems, including CRM, links with EDI, Scala, ERP, control and monitoring of ISO 9000 standards, and workflow processes.
- Adopted the code from Geofactory's GIS mapping system (La Netro), whose developers had left the company. Performed reverse engineering to help Geofactory restart its map production line. This system was eventually sold to Nokia.
- Created the portal for Cotos de Pesca (fishing preserves), which became the leader in the fishing sector in Spain and was finally sold to Editorial América Ibérica.
- Implemented the database system and the front-end operating system of the real-time license plate reading surveillance system to control La Moraleja, the most exclusive large urbanization in Madrid.
- Designed and implemented 20+ significant software projects related to engineering for various public administration bodies in Spain. I did this in collaboration with SICE, a systems integration technology company.
- Implemented dynamic data presentation and animation functionalities for a web UX with JavaScript.
Project Manager and Software Developer
Intecsa Internacional (ACS Group)
- Conceptualized, redrafted, and presented 6+ successful urban services control system contracts for Barcelona City Council.
- Led the development of a dam exploitation management system for the Spanish Ministry.
- Converted the diisopropyl ether (DIPE) system from VAX/VMS and DMRS to Unix/DOS and Oracle for Telefonica de España.
- Led conceptualization, drafting, writing, and budgeting for 15+ IT bids to public state tenders.
- Developed a street cleaning control system that integrates remote terminals and other resources to control subcontractors and cleaning processes.
- Built a control system for the collection of solid urban waste, covering collection services and the assignment of weights taken on the scale.
Software Analyst and Developer
Intecsa Internacional (ACS Group)
- Developed a software system for road layout for the Spanish Ministry of Transport.
- Built a multimedia system for organizing and presenting civil works. It was used by Dragados for several years to present its biggest offers. I built this in MicroStation MDL (C and C++) as my final graduate-level university project.
- Created a verification system for linear works regulations for the Spanish Ministry of Transport.
- Built a system to monitor and manage public construction works.
Analyst and Software Developer
Software Ibérica 92
- Designed and implemented the restructuring of the management system and the conversion to a multicompany and local area network for Industrias Protecno SA.
- Defined and executed the complete management system and application for CECOM SA.
- Designed and implemented the warehouse control, billing, and accounting software and the software application for a POS terminal for Franquicias de la Moda SA.
- Defined and delivered a multi-warehouse, multi-type manufacturing control system for Interisa Electronica SA.
- Designed and implemented a complete management software system and POS terminal.
Software Developer
Software Ibérica 92
- Developed a multi-warehouse management system with various breakdown levels and multi-select self-reporting in a geo-split environment with automatic margin adjustments, priority selection, and group creation.
- Built a reporting system to track sales against a budget plan, along with subsequent analysis charts.
- Developed a budget-based economic reporting system, including break levels down to vendors and multi-select reporting.
Experience
Data and AI Division: Technical Enablement and Innovation
Key Focus Areas:
• Training and Formation: Designed the end-to-end data and AI training curriculum. Personally supported engineering teams across the full lifecycle, including onboarding, technical formation, and production readiness.
• Centers of Excellence (CoE): Established and managed technical CoEs focused on modern data platforms and MLOps, driving comprehensive certification pathways for Dataiku, MS Fabric, Snowflake, and Databricks.
• Commercial Enablement: Formed a bridge between engineering and business development by training the commercial team on AI positioning and mentoring senior engineers to act as pre-sales technical authorities.
• R&D and Prototyping: Accelerated time-to-market for enterprise clients by standardizing proof-of-concept (POC) workflows and creating scalable architecture blueprints for RAG, LLM applications, and agentic systems.
Data and AI Division: Strategic Design and Team Formation
Key Focus Areas:
• Strategic Roadmap: Formulated a multi-year vision connecting advanced AI capabilities directly to market differentiation and business value.
• Organizational Architecture: Structured the division from zero, defining roles for specialized squads including Dataiku, MS Fabric, Python AI, front-end AI, and Snowflake.
• Resource Optimization: Authored the hiring strategy to correct misalignments, securing approval for critical hires while restructuring workflows to free senior AI specialists for high-value innovation.
• Talent Acquisition: Directed end-to-end technical recruitment, defining engineering standards and leading the selection process to scale the practice.
• Operational Framework: Established the engineering culture, implementing communication best practices, robust shared documentation, and a framework for execution excellence.
Data and AI Division: Commercial Strategy and Full Delivery Ownership
Key Focus Areas:
• Commercial Authority: Authored and signed 100% of data and AI Statements of Work (SOWs) and led daily pre-sales operations to defend complex technical architectures before enterprise buyers.
• Enterprise Engagement: Served as the primary technical authority at major industry events, including the Snowflake Summit 2025 and AI Unveiled, closing strategic conversations for Fortune 500 and private equity clients such as Blackstone and Hitachi Energy.
• Delivery Accountability: Maintained absolute ownership of project outcomes across all practice engagements, ensuring engineering delivery aligned precisely with client business goals.
• Hands-on Technical Leadership: Remained close to the keyboard by conducting architecture reviews, writing code, and leading high-stakes troubleshooting to guarantee the execution quality of production AI systems.
AIChat - Enterprise Banking Document Intelligence and RAG System
Key Focus Areas:
• System Architecture: Engineered a secure, enterprise-ready RAG pipeline utilizing Azure OpenAI and LangChain to process multi-format financial documentation while adhering to strict compliance and privacy standards.
• Document Intelligence: Implemented advanced semantic parsing and context-aware chunking strategies tailored for high-density banking records, minimizing data extraction errors and hallucinations.
• Vector Optimization: Designed vector search and embedding indexing pipelines to guarantee low-latency, highly accurate retrieval under intensive, concurrent enterprise workloads.
• Production Delivery: Guided the complete development lifecycle from initial proof-of-concept to production deployment, ensuring zero-trust security standards and seamless back-end system integration.
Insights Generator - AI-powered Data Analysis Platform
Key contributions: a dual-module architecture with specialized modules for product reviews and group chats; a scalable processing pipeline that uses batching to handle text exceeding model token limits; advanced prompt engineering with staging and grounding techniques to minimize hallucinations; a semantic clustering system that identifies dominant topics while keeping references to source text for verification; a comprehensive insights framework generating summaries, key topics, statistical analysis, and recommendations; a natural language query interface enabling non-technical users to explore data; and Azure cloud integration for scalable, secure, compliant deployment.
Next Best Offer for Banking - AI-powered Customer Engagement Platform
https://www.linkedin.com/posts/cesarzea_ai-generativeai-machinelearning-ugcPost-7246445424444682240-zQzX/?utm_source=share&utm_medium=member_desktop&rcm=ACoAAACG4NMBbtKrcccUzuhJDg7RHSH3YtvmynwThis Next Best Offer (NBO) platform uses machine learning and predictive analytics to identify the most suitable banking products for each customer, calculate expected revenue impact, and generate personalized communications to maximize conversion.
Key contributions: a machine learning pipeline analyzing demographics, account history, transaction patterns, and product holdings to predict subscription probability; multi-faceted customer segmentation combining RFM analysis with behavioral patterns; predictive revenue modeling of direct and indirect ROI per recommendation; an interactive campaign dashboard surfacing top cross-sell prospects; LLM-generated personalized sales communications; a flexible data ingestion system supporting file upload, database connections, or existing segmentation systems; an intuitive web interface for configuring parameters and visualizing results; and an optional 'Advisor' plugin adding deeper customer insights and visualizations for decision-makers.
VoiceRAG: Real-time Voice Assistant with Retrieval-augmented Generation
https://www.cesarzea.com/history.htmlKey contributions: a real-time voice interface using the GPT-4o Realtime API for audio, enabling fluid conversations without turn-based limitations; a sophisticated Real-Time Middle Tier (RTMT) bridging the front end to Azure OpenAI via bidirectional WebSockets; RAG integration with Azure AI Search to retrieve and reference knowledge-base information for more accurate answers; custom financial tools to retrieve product balances, list products, and execute transactions like transfers; a responsive React and TypeScript front end with audio recording and playback, document display, and conversation feedback, styled with TailwindCSS; a secure, personalized architecture authorizing actions by user identity; robust error handling with graceful degradation; and an extensible, scalable design for easily adding new tools. It serves as both a functional prototype for voice-based financial services and a reference implementation of the VoiceRAG pattern.
Remote Control System for Public Lighting and Ornamental Fountains for Madrid City Council
Performance:
• 3,000+ remote PLCs are near real-time telecontrolled.
• 126,000+ source lights are telecontrolled.
• 4 million+ events and measures are performed each year.
• Near real-time supervision and telecontrol are provided.
Additional accomplishments: I also designed and implemented a BI analytics portal to analyze and verify compliance indicators for the Madrid remote control lightning and ornamental fountains service. As the only developer on this very large and complex project for more than seven years, I delivered all the implementations, maintenance, and evolutions on a part-time basis.
SQL Server Integrator Controller and Supervisor
SQL Server technologies:
• Ultra-speed data transfers using BCP parallel processes and multi-disks caches.
Three synchronization technologies:
• Amazon AWS-DMS Service is automatically controlled via Amazon API Gateway.
• Partial ultra-speed full update.
• Checksum of each record calculated in each server, transferring only the changes.
Technical details:
• All data processes were programmed in T-SQL.
• Java back end supports the front end and links with Amazon AWS-DMS using the Amazon API Gateway.
• Node.js utilities control quick actions of Amazon AWS-DMS, using the Amazon API Gateway for some purposes not implemented inside the Java back end.
• Ext JS front end.
SQL Server Git Schema and T-SQL Version Control
Automatic Git logging of SQL Server T-SQL source code and schema changes happen at the server-side without any action from developers. Al schema changes and all T-SQL source code changes are registered into Git. It is inside the SQL Server where the change is detected and logged, not in the clients. You'll forget that it's installed until the moment you need it.
Key features:
• The changes are detected and recorded by the SQL Server itself.
• All changes are logged without the intervention of developers.
• It's easily adaptable so that the changes made by certain user accounts are not recorded, thus avoiding recording the changes made in the schemas by the BI processes, data warehouse, etc.
Telepizza Database Server Migrations, Optimization, and Consolidation in the Production Environment
Goals: Safe migration, consolidation, and performance improvements in a non-stop production environment. This involved upgrading from SQL Server 2000 to the last SQL Server version, ensuring complete empirical testing and documentation from an engineering perspective.
Requirements:
• 100% verification of the migrated T-SQL code with sufficient unit tests to verify code coverage.
• 100% code coverage, a record of tests performed, and verification of results.
• 100% verification of views and migrated data.
• Increased performance with the same stress and load in production.
• Hot migration performed in production systems.
Results:
• 100% compliance with the project requirements.
• Zero incidents in the hot migration of the systems in production.
• Reduced 12 servers to two servers.
• Completed the project within the budget and other terms with no incident.
• Received congratulatory feedback from the client.
Education
Computer Engineering in Computer Science
Polytechnic University of Madrid - Madrid, Spain
Certifications
Dataiku Developer Certificate
Dataiku
MLOps Practitioner Certificate
Dataiku
Dataiku Advanced Designer Certificate
Dataiku
Machine Learning Practitioner Certificate
Dataiku
Dataiku Core Designer Certificate
Dataiku
Sencha MVP
Sencha
Skills
Libraries/APIs
Node.js, API Development, React, Chart.js
Tools
DataGrip, Sencha UI, Sencha Cmd, IntelliJ IDEA, Jira, Git, pfSense, Postman, SoapUI, Azure OpenAI Service
Languages
SQL, Transact-SQL (T-SQL), JavaScript 6, Java, JavaScript, Python, Snowflake, TypeScript
Frameworks
Ext JS, Sencha Touch, .NET, Apache Spark, JavaScript MVC, Flask, Tailwind CSS
Storage
Microsoft SQL Server, Service Broker, JSON, SQL Server Integration Services (SSIS), SQL Server Reporting Services (SSRS), MySQL, PostgreSQL, Data Pipelines
Paradigms
ETL, ETL Implementation & Design, Business Intelligence (BI), Continuous Integration (CI), Automation, Distributed Computing
Platforms
Dataiku, Microsoft Fabric, Amazon Web Services (AWS), Docker, Jupyter Notebook, Azure AI Search
Other
Full-stack, Data Engineering, SSH, Data Management, Performance Tuning, Solution Architecture, Technical Leadership, Presales, Software Analysis, Data Warehousing, VMware ESXi, ETL Development, Data Mining, Data Warehouse Design, Artificial Intelligence (AI), Generative Artificial Intelligence (GenAI), Machine Learning, Agentic AI, Team Leadership, Amazon API Gateway, SOAP, AWS Database Migration Service (DMS), RAG Systems, Deep Learning, Stakeholder Management, Team Building, Technical Training, Strategic Leadership, Strategic Planning, Predictive Modeling, Model Evaluation, Feature Engineering, Data Science, Supervised Learning, Model Deployment, Machine Learning Operations (MLOps), Model Monitoring, Model Lifecycle Management, CI/CD Pipelines, Model Governance, Plugin Development, Data Preparation, Data Transformation, Partitioning, Data Quality, Automated Data Flows, Data Cleaning, Data Visualization, Front-end, Visual Recipes, Tech Sales, System Architecture, Document Indexing, Azure AI Document Intelligence, LLM Reasoning, LLM Integration, Prompt Engineering, Natural Language Processing (NLP), OpenAI, Semantic Clustering, Batched Processing, Predictive Analytics, Large Language Models (LLMs), RFM Analysis, Customer Segmentation, Azure Blob Storage, WebSockets, Real-time Audio Processing, Retrieval-augmented Generation (RAG), Generative Pre-trained Transformer 4 (GPT-4)
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