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Alexandre Szilagyi

@alexandreszilagyi

Senior Software Engineer at Prosigliere, leading a Go migration of two payment systems and building real-time risk and fraud systems.

Brazil

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At Prosigliere, I led the migration of two payment systems from C#/.NET to Go, running both stacks in parallel until parity was verified with no disruption to live payments. I also built a differential testing harness that cut regression QA time by 70%.

At Coinbase’s Risk Platform, I developed backend microservices for real-time risk decisions and improved ACH withdrawal hold accuracy, reducing false-positive holds by 4%. I also built a Kafka-based data ingestion path from MongoDB into Snowflake and Databricks.

At Mercado Pago, I developed Go APIs integrating payment gateways with accreditation partners, supporting transaction volumes of up to 16M per day. I built a DynamoDB-backed idempotency layer to prevent duplicate payment submissions when requests were retried.

Experience

Work history, roles, and key accomplishments

Current

Senior Software Engineer

Current

Prosigliere

Dec 2025 - Present (10 months)

Built a differential testing harness for payment parity, designed an automation and inventory engine, and led migration of payment systems from C#/.NET to Go. Also built invoicing and PTO features for an internal HR platform.

Go TypeScript React Next.js MindBody Online Differential Testing Payment Systems C#.NET Migration HR Platforms

Software Engineer

Coinbase

May 2025 - Dec 2025 (7 months)

Developed and maintained backend microservices for the risk and fraud prevention platform, improving withdrawal hold accuracy and reducing false positives. Built data ingestion paths and consolidated MongoDB schemas.

Go Python Kubernetes MongoDB Redis DynamoDB Kafka Snowflake Databricks Change Data Capture Microservices

Senior Software Engineer

Zup Innovation

Aug 2024 - May 2025 (9 months)

Built event-driven pipelines for document issuance and a service-contracting platform for Itaú partner services. Authored Terraform modules and infrastructure test tooling.

Go Java Kafka AWS Lambda Amazon SQS SNS Terraform PostgreSQL Event Driven Architecture

Senior Software Engineer

Mercado Livre

Dec 2022 - Aug 2024 (1 year 8 months)

Developed and maintained critical Go APIs for the Mercado Pago payment gateway, processing up to 16M transactions per day. Managed HSM-backed security keys and improved deployment processes.

Go DynamoDB HSMs PCI PII CI CD Idempotency Distributed Systems Events API

Software Engineer

Zup Innovation

May 2021 - Dec 2022 (1 year 7 months)

Developed a cloud-based Rural Credit payments solution in Go, Python, Java/Spring Boot, and Kafka, reducing settlement time by 83%. Built ingestion and reporting pipelines and authored Terraform modules.