João Rocha, Developer in Florești, Cluj County, Romania
João is available for hire
Hire João

João Rocha

Verified Expert  in Engineering

Data Warehouse Design Developer

Florești, Cluj County, Romania
Toptal Member Since
October 13, 2020

João has extensive experience developing data applications using a broad range of tools and technologies across different industry sectors. João can effectively apply data warehousing and data engineering methods and techniques to solve complex data problems using relational databases, the Hadoop ecosystem, and cloud infrastructure.


GitLab CI/CD, Kubernetes, RocksDB, HBase, Apache NiFi, Spark, Apache Kafka...
Sagacity Solutions
Amazon Web Services (AWS), Netezza, Teradata, MySQL, Databricks, Apache Hive...
Harte Hanks
Unix Shell Scripting, Oracle, PL/SQL, SQL




Preferred Environment

Oracle Exadata, Teradata, UML, Kafka Streams, Spark, Java, SQL, Python, Data Engineering, Data Warehousing, Data Warehouse Design

The most amazing...

... analytics solution I've implemented included forecasting tenure and cash flow for a large telecommunications company's entire customer base.

Work Experience

Senior Analyst | Data Engineer

2018 - 2020
  • Developed Kafka Streams applications supporting an event-driven architecture with microservices.
  • Collaborated on creating a CI/CD pipeline for Kafka Streams applications, migrating to containers, and Kubernetes orchestration.
  • Developed Spark Streaming applications to consume data from Kafka and load a fund data management data model in HBase.
  • Implemented NiFi processor groups to integrate data sourced from files via FTP.
  • Contributed to data modeling for fund data management.
Technologies: GitLab CI/CD, Kubernetes, RocksDB, HBase, Apache NiFi, Spark, Apache Kafka, Kafka Streams, Java

Senior Developer

2017 - 2018
Sagacity Solutions
  • Developed a bespoke value-based management analytics solution for the telecommunications company Telstra. The solution within a data warehouse supported by Teradata included modules for tenure, cash flow forecasts, and investment data integration.
  • Designed and developed a configuration-driven product for value-based management using Apache Spark, standardizing the core algorithms.
  • Supported the implementation of a value-based management product for the telecommunications group Tele2 in Estonia, Latvia, and Lithuania.
  • Oversaw a value-based management product operating in a Software as a Service (SaaS) model using AWS.
  • Implemented the ETL steps to the data warehouse supported by Netezza, enabling a revenue assurance process related to call-center operations for the telecommunications company TalkTalk.
Technologies: Amazon Web Services (AWS), Netezza, Teradata, MySQL, Databricks, Apache Hive, Spark, SQL, Python

Senior Developer

2016 - 2017
Harte Hanks
  • Contributed to the evolutionary maintenance of a single customer view (SCV) solution, a bespoke multi-source marketing database supported by Oracle created for software company VMWare.
  • Designed and developed ETL processes for marketing data using PL/SQL in an Oracle database.
  • Optimized performance by reviewing long-running SQL queries.
Technologies: Unix Shell Scripting, Oracle, PL/SQL, SQL

Data Warehouse and Business Intelligence Consultant

2014 - 2016
WeDo Technologies
  • Designed and developed a sales dashboard for a retail company using Microsoft Analysis Services, including a new data mart and ETL processes within a data warehouse supported by Oracle Exadata.
  • Gathered requirements, researched, and created a business case for a group-level sales reporting dashboard for Sonae SGPS.
  • Led the implementation of an analytics solution providing supply chain performance metrics for the retail company Sonae SR. Implemented the reports in MicroStrategy.
  • Developed an analytics solution providing out-of-stock indicators for Sonae MC and implemented reports in Oracle Business Intelligence.
  • Implemented an analytics solution containing retail sales indicators for different business models used in specialized retail for Sonae SR, utilizing Microsoft Analysis Services.
  • Designed an operational data model for retail based on the NRF ARTS data model.
Technologies: Oracle Retail, Oracle Exadata, Oracle, PL/SQL, SQL

Business Analyst

2011 - 2014
Wipro Retail
  • Designed and developed an operational reporting framework within an Oracle Retail environment using PL/SQL and Oracle Business Intelligence.
  • Implemented a set of operational reports for a retail company covering supply chain, finance, and commerce. Built reports using a custom operational reporting framework in Oracle Business Intelligence.
  • Developed a set of custom financial operational reports for the retail company Morrisons, using Oracle Business Intelligence during the Oracle Retail implementation project.
  • Designed and developed an analytics solution for Sonae MC containing metrics for supplier service levels. The solution included a data mart and ETL processes within the data warehouse supported by Oracle Exadata.
Technologies: Oracle Business Intelligence Applications (OBIA), Oracle Retail, Oracle Exadata, PL/SQL, SQL

IT Consultant

2010 - 2011
  • Designed and developed a balanced scorecard for Sonae MC's retail branch operations, including a data model and integration processes within a data warehouse supported by Oracle Exadata, C#, and ActionScript.
  • Collaborated on the evolutionary maintenance of a retail sales dashboard, with the front end built using ActionScript.
  • Contributed to the evolutionary maintenance of a sales data pipeline within a data warehouse supported by Oracle Exadata.
Technologies: C#, Oracle Exadata, PL/SQL, SQL

Data Warehouse and Business Intelligence Consultant

2008 - 2010
Vass Consultoria de Sistemas
  • Collaborated on creating a new enterprise data warehouse for the Spanish bank BBVA by building the warehouse with Teradata and ETL processes, mainly using Informatica PowerCenter. Designed and developed ETL.
  • Developed the ETL processes within the data warehouse system of Santander Bank, supported by an Oracle database and Informatica PowerCenter.
  • Engaged in the data warehouse system's evolutionary maintenance for a telecommunications company, supported by an Oracle database and Informatica PowerCenter.
Technologies: Unix Shell Scripting, Informatica PowerCenter, Java, Teradata, PL/SQL, SQL

KNEIP Digital Platform
KNEIP wanted to build a complete digital platform for fund data management, handling the entire life cycle of fund data, integrating multiple sources, and supporting numerous reporting and publishing targets in different media.

I was a senior data engineer within a cross-functional team responsible for supporting real-time data integration from various sources into a data model capable of supporting multiple products. The platform implemented an event-driven architecture with microservices. I was heavily involved in developing the data ingest pipeline using Apache NiFi, Kafka Streams, Apache Spark, and HBase.

VBM Product

VBM stands for value-based management. It is a solution that helps businesses improve their profitability by providing detailed customer-level insight on which customer delivers the most value. It also creates an appropriate and sustainable approach to administration and shapes a culture that focuses on long-term value creation.

I served as the lead developer to create a configuration-driven product containing VBM's core modules, namely tenure, cash flow forecasts, and investment data integration. Participating in different implementations of this product, I delivered client-specific customization and supported technical deployment in different environments, such as AWS cloud and on-premises Hadoop cluster. The product is written in Python and supported by Apache Spark.
2002 - 2008

Master's Degree in Computer Science and Informatics Engineering

Faculty of Engineering, University of Porto - Porto, Portugal


Kafka Streams, Oracle Exadata, Apache NiFi, GitLab CI/CD, Oracle Business Intelligence Applications (OBIA), Informatica PowerCenter


PL/SQL, Teradata, Exadata, Databases, HBase, RocksDB, Apache Hive, MySQL, IBM Db2, Netezza


SQL, Java, Python, UML, ActionScript 3, C#


Hadoop, Spark


Oracle, Apache Kafka, Kubernetes, Databricks, Oracle Retail, Amazon Web Services (AWS)

Industry Expertise

Project Management


Data Warehousing, Software Engineering, Data Warehouse Design, Data Engineering, Computer Science, Distributed Systems, Web Technologies, Statistics, Unix Shell Scripting

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.


Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring