FullStackHero .NET Starter Kit is a production-ready boilerplate for building multi-tenant SaaS applications with a .NET 10 backend and React frontends.
The kit addresses the challenge of implementing complex, cross-cutting concerns that typically consume significant development effort: multitenancy, authentication, billing, auditing, background jobs, real-time communication, file storage, and observability. Rather than providing a minimal scaffold, it ships with these systems fully implemented and integrated. The backend uses a modular monolith architecture organized around vertical slices, with a .NET 10 API built on Minimal APIs and source-generated CQRS via Mediator. It includes EF Core 10 with PostgreSQL, JWT authentication with ASP.NET Identity, tenant isolation via Finbuckle, HybridCache on Valkey, Hangfire for background jobs, and OpenTelemetry for observability. The frontend consists of two React 19 applications—an admin console and a tenant dashboard—both built with Vite, TypeScript, TanStack Query, and Radix UI components. All code is provided as source, not as black-box packages, allowing full ownership and modification.
Teams building multi-tenant SaaS platforms or applications requiring sophisticated identity, billing, and audit capabilities should consider this kit. It suits projects where the overhead of implementing these systems from scratch outweighs the cost of adopting an opinionated structure. The kit is particularly valuable for teams wanting to avoid reinventing authentication flows, tenant isolation patterns, and observability infrastructure. It includes scaffolding via a CLI tool and local orchestration through .NET Aspire, enabling rapid local development and deployment to Docker or AWS.
The project maintains active development with regular updates to align with current framework versions. The codebase demonstrates consistent attention to production concerns, including security auditing, rate limiting, idempotency, and structured logging. Architecture is enforced through automated tests that validate module boundaries. Documentation is comprehensive, covering getting started, module structure, and architectural decisions. The kit includes end-to-end test suites written in Playwright for the frontend applications.
