Can I vibe code Shopware?

Build a specialized e-commerce checkout and dynamic pricing microservice tailored for European B2B/B2C merchants using Node.js, Express, and PostgreSQL.

Entities to implement:
1. Product: id, sku, name, tax_category_id, base_price, dynamic_matrix (jsonb for quantity tiers).
2. CustomerGroup: id, name, tax_display_type (gross/net), custom_discount_percentage.
3. OrganizationUnit: id, parent_id, company_name, spending_budget, budget_period (monthly/annual).
4. Rule: id, name, priority, conditions_json (e.g., cart_value > 500 AND country == 'DE'), action_type (discount_percent, set_shipping, adjust_tax), action_value.
5. Cart: id, customer_group_id, organization_unit_id, items (array of product_id, quantity), calculated_tax, total_net, total_gross.

Core Calculation Engine Requirements:
- Write an explicit tax calculator that applies EU country-specific VAT rules (e.g., standard rates vs. reduced rates, cross-border reverse charge rules when a valid EU VAT ID is supplied).
- Support customer-group specific net vs. gross price renderings at both item and cart summary levels.
- Implement a B2B budget-check middleware: before checkout confirmation, evaluate if the order total exceeds the assigned OrganizationUnit spending_budget.
- Implement a rule engine evaluator function that processes array of Rules in order of priority, mutating the cart total conditionally based on cart properties.

API Endpoints:
- POST /api/cart/calculate: Accepts cart contents, shipping country, and customer context; returns detailed tax breakdown, active rule applications, and net/gross totals.
- POST /api/b2b/quote/request: Creates a structured quote draft from a cart state if cart total exceeds target thresholds.
- POST /api/b2b/budget/check: Validates if an organization unit has remaining balance.

Out of Scope:
- Front-end storefront rendering or visual page builder.
- Native payment processing gateway integrations.
- Third-party ERP background sync schedules.

Include comprehensive unit tests for the EU tax calculation and B2B budget validation logic using Jest.

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