Multi-Tenant Inventory ERP

Small manufacturers often sit between spreadsheets and a full MRP system. This ERP gives each business its own workspace, at its own URL and with its own database, to run its product and materials catalogue, bills of materials, stock across sites and warehouses, purchase and sales orders, returns and physical stock counts.

Stock correctness is the core. A single StockService is the only code allowed to write stock: every change becomes a signed ledger entry, stock can never go below zero, quantities use decimal-safe bcmath maths, and locks are always taken in a fixed order so concurrent transfers can't deadlock.

The codebase is built to stay maintainable: thin controllers calling domain Actions and Services, typed DTOs whose TypeScript types are generated and committed, PHPStan at level 7 with no baseline, and custom check scripts that keep every Laravel FormRequest in sync with its zod schema.