Tenant-Isolated EF Core Repositories on Par with MongoDB Multi-Tenancy

[tsutomi]

"Give teams building multi-tenant applications on relational databases the same one-API, zero-leakage tenancy experience that MongoDB users have today."

The Problem Today
Deveel.Repository.MongoFramework.MultiTenant provides a robust connection-per-tenant isolation model. The EF Core driver has no equivalent: teams building multi-tenant applications on SQL Server or PostgreSQL must implement tenant filtering manually through EF Core global query filters or per-query predicates — with no repository-level convention, tooling, or isolation guarantees from the framework.

What We Are Building

• An IDbTenantContext service that provides the current tenant identifier to the EF Core driver
• Automatic global query filter registration for entities implementing IHaveOwner<TTenantId> — no per-query filtering required
• A schema-per-tenant strategy option routing each tenant to a named database schema
• A database-per-tenant strategy option using tenant-specific connection strings, paralleling the MongoDB model
• An integration adapter for Finbuckle.MultiTenant (the de-facto .NET multi-tenancy library)

Benefits

• SQL-backed multi-tenant applications use the same repository API as single-tenant ones
• Zero cross-tenant data leakage — isolation is enforced at the driver level, not trusted to application code
• Teams already using Finbuckle.MultiTenant get native integration without any glue code
• Feature parity with MongoDB multi-tenancy — driver choice no longer dictates multi-tenancy capability