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Leonardo Dumont Wahhab

@leonardodumontwahhab

Back-End Developer at Revizia who reduced document-import processing errors by 75% in an AWS event-driven system.

At Revizia, I developed Java and Spring Boot features for a tax and fiscal control system built around REST APIs, microservices, and AWS. I restructured its event-driven document-import workflow, reducing processing errors by 75%.

I adapted the invoicing module to Brazil's tax reform, extracting tax values from XML, generating invoices, and exporting fiscal analysis reports. I also optimized PostgreSQL queries and wrote automated tests with JUnit and Mockito.

At ClearSale, I provided technical support for anti-fraud analysis platforms, tested REST APIs, and maintained client records with SQL Server. I also built support process documentation to reduce lookup time and improve team training.

Experience

Work history, roles, and key accomplishments

Back-End Developer

Revizia

Aug 2024 - Jul 2026 (1 year 11 months)

Developed new features using Java 11 and Spring Boot for a tax and fiscal control system built on REST APIs within a microservices architecture integrated with AWS cloud and asynchronous messaging. Restructured the document-import workflow within an event-driven architecture, reducing processing errors by 75% and streamlining queue throughput.

Technical Support Analyst

ClearSale

Apr 2023 - Jul 2024 (1 year 3 months)

Provided technical support to internal and external clients on access management, system errors, and configuration issues within anti-fraud analysis platforms. Managed support ticket workflows using Zendesk, achieving a customer satisfaction rate above 90%.

Zendesk SQL Server REST APIs Postman Swagger Documentation