Billing SaaS v1.0.0 — Initial Enterprise Release 🚀

Billing SaaS v1.0.0 — Initial Enterprise Release 🚀

This is the first official release of the Billing SaaS platform — a full-stack, multi-tenant, enterprise-grade subscription billing system built with Java Spring Boot, PostgreSQL, MongoDB, Redis, Kafka, and Resilience4j.

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🔹 Key Features

• Subscription Management 🏢

  • Create, update, suspend, cancel subscriptions
  • Multi-tenant support with tenant isolation

• Invoice & Payment Handling 💳

  • ACID-compliant invoice creation
  • Stripe payment integration (async with retry)
  • Payment webhook handling

• Event-driven Architecture ⚡

  • Kafka producer/consumer for domain events
  • Dead-letter queues for failed messages
  • Asynchronous notifications (email, SMS, push)

• Authentication & Security 🔑

  • JWT + OAuth2
  • RBAC per tenant
  • User, roles, tenant stored in PostgreSQL

• Caching & Performance ⚡

  • Redis caching for plans, configs, tenant data
  • Read/write separation: PostgreSQL (write), MongoDB (read/analytics)

• Resilience & Observability 🔄

  • Circuit breaker, retries, timeouts
  • Metrics via Micrometer + Prometheus
  • Structured logs and health endpoints

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🔹 Chores / Setup

• PostgreSQL, MongoDB, Redis configuration for multi-tenant support
• Maven dependencies added: Kafka, Resilience4j, Redis, MongoDB
• Spring Profiles for dev, qa, and prod
• Initial DB schema created for subscription, invoice, payment, auth

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🔹 Hotfixes / Fixes

• Corrected invoice rounding calculation
• Fixed payment retry logic for failed transactions
• JWT refresh token bug fixed for multi-tenant auth

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🔹 Testing

• Unit tests for subscription, invoice, payment, notification modules
• Integration tests for Kafka events and retries
• QA tests for multi-tenant flows

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🔹 Notes

• This release follows DDD principles and is production-ready
• Multi-tenancy, audit logging, and observability are enabled from day one
• Semantic versioning is used for all future releases

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🔹 Next Steps

• Frontend UI integration
• Reporting & analytics microservices
• Horizontal scaling and tenant onboarding improvements