Rafael Ignaulin
Senior Data & AI Engineer
- rafa@ignaulin.com
- www.linkedin.com/in/rafa-ignaulin/
- Remote, Global (15+ countries)
Professional Summary
Senior Data & AI Engineer with 5+ years in data engineering, building production AI systems on large-scale data platforms. Built, as sole engineer, an LLM agent that turns plain-English questions into SQL and an MCP server that connects analytics to AI coding assistants, on top of billions of rows of clickstream data on Databricks, Spark and Airflow. Delivers for Nike and Inter&Co as an independent contractor through ISTech, a self-founded consultancy; previously at PagSeguro/PagBank via Compass.uol. Has worked from 15+ countries with teams in the US, Canada, Europe, India and Australia, always on client hours.
Key Achievements
- Built a production LLM analytics agent at Nike as sole engineer (Claude Sonnet, Streamlit, MLflow) that turns plain-English questions into SQL
- Built Nike's analytics MCP server as sole engineer (FastMCP + FastAPI), exposing internal analytics APIs to Cursor with YAML-driven tool registration
- Cut Spark data reads 98% on a daily Nike job (multi-terabyte runs down to tens of GB) with partition and column pruning
- Automated Nike's A/B test reporting end to end with Airflow, from weeks of manual Excel work to a few hours
- Major contributor to the session-level clickstream table powering Nike's Marketing and Digital Experience analytics (billions of rows, Databricks/Spark/Airflow)
- Own end-to-end the client segmentation platform at Inter&Co, a digital bank with 45M+ customers
- Founded ISTech, a B2B data engineering consultancy delivering to US enterprise clients across 6+ timezones
Experience
Founder & Principal Data & AI Engineer · ISTech (Own Consultancy)
- Founded the B2B consultancy all contract work below runs through, building Data Warehouses and Lakehouses on AWS/Azure with Spark, Kafka, Airflow and Terraform for clients including Nike and Inter&Co.
- Delivered from 15+ countries across 6+ timezones while holding enterprise contracts, always aligned to client hours.
Senior Data Engineer (Marketing & Digital Experience) · Nike (Contract via ISTech)
- Cut Spark data reads 98% on a daily job (multi-terabyte runs down to tens of GB) with partition and column pruning.
- Automated A/B test reporting end to end with Airflow: weeks of manual Excel work down to a few hours, with consistent readouts.
- Major contributor to the session-level clickstream table (billions of rows, hundreds of GB, millions of rows added daily) powering Marketing and Digital Experience analytics on Databricks/Spark/Airflow.
- Built an LLM analytics agent (Claude Sonnet, Streamlit, MLflow) turning plain-English questions into SQL, with confidence scoring on every answer.
- Built a FastMCP/FastAPI server exposing a dozen-plus analytics tools to Cursor via YAML-based tool registration, so adding a tool needs no code change.
Data Engineering Lead (Client Segmentation) · Inter&Co (Contract via ISTech)
- Own end-to-end a client segmentation platform (Spark, Kafka, Delta Lake) for a digital bank with 45M+ customers.
- Built a 6-zone medallion lakehouse on S3/Delta Lake, from data modeling to orchestration with Airflow across EMR and Kubernetes.
- Designed CDC ingestion (Kafka/MSK, Debezium) and a near-real-time update engine keeping segmentation current between batch cycles.
- Built a reusable data-quality framework adopted across every ingestion pipeline on the platform.
- Extended the platform to the bank's US operation.
- Designed the platform's core segmentation logic and set the engineering standards (testing, CI/CD, alerting) across the team's 8 repositories.
- Progressed Mid-Level → Senior → Lead across the engagement.
Data Engineer (Junior → Mid-Level) · PagSeguro / PagBank (via Compass.uol)
- Data modeling and query tuning for an Amazon Redshift data warehouse (star/snowflake schemas) across 20+ tables with billions of rows, for a 10x performance gain.
- Promoted Junior → Mid-Level; transitioned out in Oct 2024 as ISTech contract work became the focus.
Skills
Languages
Python, SQL
Big Data & Streaming
Spark, PySpark, Kafka, Flink, Debezium, Confluent Schema Registry
Cloud
AWS (S3, EMR, Redshift, DynamoDB, Lambda), Azure
Data Platforms
Databricks, Snowflake, Delta Lake, Unity Catalog
Orchestration & IaC
Airflow, Dagster, Terraform, Docker, Kubernetes
Databases
Redshift, PostgreSQL, DynamoDB, Trino, Presto, Athena
AI & Agentic
MCP Servers, FastMCP, LLM Integration, RAG, Prompt Engineering, Cursor AI, MLflow
BI & Visualization
Tableau, Databricks AI/BI, Power BI, Streamlit
APIs & Frameworks
FastAPI, asyncpg, httpx
Education
M.S. Computer Science (OMSCS) · Georgia Institute of Technology
Bachelor in Computer Science · Unochapecó
Academic Honor Medal: highest grade in the graduating class (~100 students)
Certifications
- AWS Certified Solutions Architect - Professional
- AWS Data Engineer Associate
- AWS Black Belt
- Microsoft Azure Solutions Architect Expert (AZ-305, 2023-2025)
- Databricks Data Engineer Professional
- Astronomer Certification DAG Authoring for Apache Airflow 3
- Astronomer Certification for Apache Airflow 2 Fundamentals
- AWS Certified Cloud Practitioner
- AWS Certified Solutions Architect - Associate
- AWS Partner: Accreditation (Business)
- AWS Partner: Technical Accredited - Training Badge
- Oracle Infrastructure Foundations Associate
- Oracle Cloud Data Management Foundations
Languages & Work Authorization
- English: C2 (Professional Proficiency)
- Portuguese: Native
Brazilian citizen. Contracts internationally through ISTech and works in each client's time zone.