João PauloDias Ventura

Node.js · Java · Go · Angular · AWS

Software Engineer specialized in financial systems, high-throughput data processing, concurrent architecture, and high-reliability distributed systems.

SYS_ONLINE // NOMINAL ACID · DETERMINISTIC_LOCKS
01/FINFinancial SystemsTransactional Outbox · Idempotency · ACID Settlement
02/DATAData PipelinesGo Worker Pools · Bounded Channels · Streams
03/DISTDistributed ArchitectureKafka · RabbitMQ · SQS · Event-Driven Microservices
04/PERFHigh Performance1.23 GB/s · 20ms Query Latency · Zero Memory Leaks

Impact & Benchmarks

Systems performance in production.

Measured volume, low-latency indexing, and streaming concurrency derived directly from production and benchmark results.

BENCHMARK 01PostgreSQL FTS + Composite Haversine Index
20ms
latency reduction in catalog search

Migrated from sequential full-table scans to compound indices, server-side Haversine trigonometry, and client worker pre-processing.

CURRENT SCAN: 95% latency reduction

BENCHMARK 02Node.js Streams + Worker Threads
16 GB+
streaming load processed per flow

High-volume ingestion pipelines processing multi-gigabyte media without heap degradation using backpressure and worker concurrency.

BENCHMARK 03ACID Replica Sets · Transactional Outbox
R$ 1M+
automated monthly in financial operations

Reduced manual reconciliation and operational overhead from days to minutes with end-to-end auditability and zero event loss.

TRANSACTIONS // ACIDZERO EVENT LOSSDAYS → MINUTES

Career Trajectory

Progression of systemic responsibility.

Trajectory at uFind Tecnologia: from interface optimization and search latency to high-volume media pipelines and critical financial automation.
Jun 2025 - PresentFinancial Automation, ACID Transactions & Infrastructure

Mid-Level Software Engineer

uFind Tecnologia

End-to-end engineering of critical financial flows in production, spanning client architecture, microservices, databases, and infrastructure.

RESPONSIBILITY

End-to-end evolution of production financial systems, ACID transaction boundaries in MongoDB replica sets, and operational automation.

RESULTS & CONTRIBUTIONS
  • Automated financial flows exceeding R$ 1 million monthly, reducing manual operations from days to minutes with zero data discrepancies.
  • Implemented end-to-end system traceability with structured JSON logs, alerting, and real-time operational notifications.
  • Reduced payload by ~10% across flows with over 1,300 records using client-side pre-processing and the Strategy Pattern.
  • Modeled high-reliability MongoDB data schemas utilizing ACID transactions in Replica Sets to enforce strict financial consistency.
Node.jsJava / SpringMongoDB ACIDRedisStrategy PatternAWS

Featured Engineering Systems

Concurrency, consistency, and asynchronous architecture.

Production and engine case studies breaking down constraints, architectural decisions, failure modes, and benchmark results.

01 / 04 Financial Core Banking Platform

Auronix

Digital bank ledger with accounts, concurrent transfers, and payment requests using Java/Spring Boot, PostgreSQL, and RabbitMQ.

Key DecisionsTransactional Outbox

atomic database-to-broker publication with zero event loss or duplicate ledger operations

Auronix digital bank architectural case study.

Auronix // Transactional Settlement Pipeline

Demonstrates how financial transactions transition from client entry to atomic locking, outbox batching, worker execution, and real-time SSE propagation.

LOCK ACQUIRED -> BALANCE VALIDATED -> COMMIT -> EVENT DELIVERED

Core Problem & Constraints
Guaranteed balance consistency under high concurrency across simultaneous accounts and transfer operations.
Engineering Scope
End-to-end architecture & implementation of the financial ledger, outbox messaging, and settlement pipeline.
Key Decisions
Transactional Outbox with FOR UPDATE SKIP LOCKED batching, idempotent consumers by eventId, and deterministic pessimistic locks.
Outcome & Metrics
Transactional Outbox atomic database-to-broker publication with zero event loss or duplicate ledger operations
  • Java
  • Spring Boot
  • PostgreSQL
  • RabbitMQ
  • Redis
  • Angular

02 / 04 High-Throughput Compression Engine

GGCompress

Go engine for compressing large files concurrently with bounded memory consumption and verifiable binary archive formatting.

Key Decisions1.23 GB/s

peak throughput achieved across parallel worker pools on multi-core hardware

GGCompress concurrent Go engine visual.

GGCompress // Parallel Stream & Assembly Flow

Splits large input streams into bounded chunks, distributes work across Goroutine worker pools, and enforces ordered writes with SHA-256 integrity.

LARGE FILE -> BOUNDED CHUNKS -> WORKERS -> ORDERED OUTPUT -> CHECKSUM

Core Problem & Constraints
Processes multi-gigabyte files in parallel while strictly bounding heap memory through backpressure and buffer pooling.
Engineering Scope
Designed and built the concurrent Go archiving engine, streaming chunker, and memory buffer manager.
Key Decisions
Combines sequential reads, worker pools, bounded channels, ring buffer reassembly, and per-chunk SHA-256 verification.
Outcome & Metrics
1.23 GB/s peak throughput achieved across parallel worker pools on multi-core hardware
  • Go
  • Goroutines
  • Worker Pools
  • Bounded Channels
  • SHA-256
  • Binary Formats

03 / 04 Event-Driven Media Streaming Pipeline

X Tube

Distributed, event-driven video ingestion and transcoding pipeline utilizing Go, SQS, S3, FFmpeg, and Apache Kafka.

Key DecisionsS3 → SQS → Go → Kafka

fully decoupled ingestion, multi-bitrate transcoding, and progress notification flow

X Tube event-driven media pipeline visual.

X Tube // Asynchronous Media Processing Pipeline

Traces video ingestion from S3 upload notifications to Go worker pool transcoding, S3 artifact persistence, and Kafka progress emission.

UPLOAD -> CLAIM JOB -> FFMPEG -> ARTIFACTS -> EVENT PUBLISHED

Core Problem & Constraints
Decouples media upload from intensive transcoding using SQS queues and worker visibility timeout heartbeats.
Engineering Scope
Led the asynchronous pipeline architecture, queue processing, and reliable worker lifecycle in a team of 3.
Key Decisions
Workers emit Kafka progress events upon every confirmed S3 chunk upload and delete queue messages only after full success.
Outcome & Metrics
S3 → SQS → Go → Kafka fully decoupled ingestion, multi-bitrate transcoding, and progress notification flow
  • Go
  • AWS SQS
  • AWS S3
  • FFmpeg
  • Apache Kafka
  • Prometheus

04 / 04 High-Concurrency Election Platform

Vox

Realtime election platform tested with 10,000 requests and 100 concurrent accesses on AWS EC2 t2.micro, used by 500+ voters at Etec.

Key Decisions106 req/s

100% success rate across 10,000 requests and 100 concurrent users on an AWS EC2 t2.micro instance

Vox high-concurrency election platform visual.

Vox // Concurrency Boundary & Realtime Serialization

Maintains atomic vote validation, ballot-box serialization, and real-time WebSocket broadcasts without race conditions.

CONCURRENT REQUESTS -> LOCK -> COMMIT -> NEXT

Core Problem & Constraints
Enforces atomic vote serialization per ballot box via PESSIMISTIC_WRITE locks inside a single transaction boundary.
Engineering Scope
Engineered the transactional voting serialization, database concurrency boundaries, and WebSocket telemetry.
Key Decisions
Delivers real-time vote count tallies via STOMP/WebSocket without blocking critical voting database transactions.
Outcome & Metrics
106 req/s 100% success rate across 10,000 requests and 100 concurrent users on an AWS EC2 t2.micro instance
  • Angular
  • Spring Boot
  • PostgreSQL
  • PESSIMISTIC_WRITE
  • STOMP / WebSocket
  • AWS EC2

AI Agent

Ask the portfolio directly.

A deterministic question-answering console over the local portfolio knowledge base. It retrieves evidence, ranks it, reasons over the matched concepts, and abstains when the content is not supported.

Start with a concrete question.

Each request is isolated: only the question you send now is evaluated by the agent.

14 / 2048 bytes - 2048-byte request body limit

Stack & Engineering Pillars

Architecture framed around problem spaces.

End-to-end systems engineering: client interface architecture, distributed APIs, ACID storage, asynchronous message brokering, declarative infrastructure, and observability.

01 / Transactional & Financial Systems

  • Java / Spring Boot
  • PostgreSQL (Pessimistic Locks)
  • Redis (Pub/Sub & Caching)
  • Transactional Outbox Pattern
  • ACID Replica Sets

02 / Concurrent Data Processing

  • Go (Goroutines & Channels)
  • Node.js Streams & Worker Threads
  • Bounded Buffers & Backpressure
  • SHA-256 Integrity Verification
  • Vector Embeddings / Search

03 / Asynchronous & Event-Driven Systems

  • RabbitMQ (Dead-letter & Idempotency)
  • Apache Kafka (Partitioned Progress)
  • AWS SQS & SNS
  • SSE (Server-Sent Events)
  • STOMP / WebSockets

04 / Cloud Infrastructure & Observability

  • AWS (EKS, EC2, S3, Lambda)
  • Docker & Kubernetes (Kubeconform)
  • Terraform (Declarative IaC)
  • Prometheus & Micrometer
  • Structured JSON Telemetry

05 / System Interfaces & Clients

  • TypeScript & Angular (Signals & SSR)
  • Next.js & React
  • Web Workers & Off-thread Processing
  • Tauri Native Runtime
  • WCAG AA / High Accessibility

Education & Certifications

Technical foundation in continuous progress.

Formal education in Artificial Intelligence and Systems Development, complemented by deep specialized certifications in Kubernetes, event-driven architectures, distributed data, and DDD.

Education

  • FIAP | Aug 2026 - Jun 2028 | Artificial Intelligence
  • Etec de Guarulhos | Feb 2023 - Dec 2025 | Systems Development

Certifications

  • AWS: EKS and Event-Driven Architectures
  • Alura: Software Architecture & Domain-Driven Design (DDD)
  • FIAP: AI & Machine Learning Engineering
  • MongoDB: Data Modeling & Financial Services
  • EnterpriseDB: Distributed PostgreSQL Architecture

Languages

  • Portuguese (Native / Fluent)
  • English (Advanced / Professional)

Contact

Direct contact.

Public channels to discuss software engineering, financial systems, and reliable processing.

Email joaopdias.dev@gmail.com

LinkedIn linkedin.com/in/joaopdias-dev

GitHub github.com/Joaopdiasventura

LocationSão Paulo - SP