Production-ready Java infrastructure for building reliable enterprise systems.

We build open-source libraries and reference architectures for the infrastructure concerns that appear repeatedly in production systems:

• 🧠 Persistence & Query Infrastructure
• 🔍 Audit Trails
• ⚠️ Exception & Error Handling
• 📡 Reliable Event-Driven Architecture
• 🔐 Identity & Access Management
• 📊 Observability & Operations

Our goal is simple: provide battle-tested building blocks so Java teams can spend less time rebuilding infrastructure and more time building their applications.

Production-ready audit trail system built on Hibernate Envers.

• Query and inspect entity history
• Designed for real-world auditing requirements
• Extensible and modular
• Spring Boot integration

Advanced Spring Data JPA extensions for building cleaner persistence layers.

• Dynamic query specifications
• Flexible projections
• Cleaner repository abstractions
• Reusable persistence patterns

Production-ready event infrastructure for reliable event-driven systems.

• Transactional Outbox and Inbox patterns
• Reliable delivery with retries and failure tracking
• Idempotent event consumption
• Kafka and AWS SQS support
• Multi-instance safe processing
• Scheduler resilience and health monitoring
• Operational APIs for inspecting and managing events
• Broker-neutral core architecture

Built for systems where events must be reliable, observable, and easy to debug.

Standardized exception handling for Spring applications and distributed systems.

• Consistent error responses and error codes
• Spring MVC exception handling
• Feign error propagation
• Kafka integration
• Security and validation error handling
• Traceable errors across service boundaries

We provide real-world IAM implementations using:

• Keycloak (multi-tenancy, SPIs)
• AWS Cognito integrations

• Spring Cloud Microservices (Gateway, Eureka, Config) :contentReference[oaicite:2]{index=2}
• Secure React + Keycloak apps
• Dockerized infra setups

Some advanced features are available as private or paid modules, including:

• Advanced audit querying
• Multi-tenant IAM systems
• Enterprise extensions

👉 https://www.czetsuyatech.com

Built by a Java backend engineer with 15+ years experience in:

• Fintech
• Payment systems
• Cybersecurity
• Distributed systems :contentReference[oaicite:3]{index=3}

If you're building:

• SaaS platforms
• Microservices
• Secure enterprise apps

This org gives you battle-tested building blocks instead of reinventing everything.

If this helps you, consider supporting:

• GitHub Sponsors
• Sharing the projects