feat: Propagate core entities from erp-construccion

Modules added: - audit (7 entities): audit logs, config changes, entity changes - billing-usage (14 entities): subscriptions, invoices, coupons - core (13 entities): countries, currencies, UoMs, sequences - invoices (4 entities): invoices, payments, allocations - notifications (6 entities): notifications, templates, channels Total: 44 new entity files Build: Clean (0 TypeScript errors) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
2026-01-27 09:06:11 -06:00 · 2026-01-27 09:06:11 -06:00 · 8c010221fb
commit 8c010221fb
parent a0ca2bd77a
47 changed files with 3453 additions and 0 deletions
--- a/src/modules/audit/entities/audit-log.entity.ts
+++ b/src/modules/audit/entities/audit-log.entity.ts
@ -0,0 +1,116 @@
+/**
+ * AuditLog Entity
+ * General activity tracking with full request context
+ * Compatible with erp-core audit-log.entity
+ *
+ * @module Audit
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  Index,
+} from 'typeorm';
+
+export type AuditAction = 'create' | 'read' | 'update' | 'delete' | 'login' | 'logout' | 'export';
+export type AuditCategory = 'data' | 'auth' | 'system' | 'config' | 'billing';
+export type AuditStatus = 'success' | 'failure' | 'partial';
+
+@Entity({ name: 'audit_logs', schema: 'audit' })
+export class AuditLog {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Index()
+  @Column({ name: 'user_id', type: 'uuid', nullable: true })
+  userId: string;
+
+  @Column({ name: 'user_email', type: 'varchar', length: 255, nullable: true })
+  userEmail: string;
+
+  @Column({ name: 'user_name', type: 'varchar', length: 200, nullable: true })
+  userName: string;
+
+  @Column({ name: 'session_id', type: 'uuid', nullable: true })
+  sessionId: string;
+
+  @Column({ name: 'impersonator_id', type: 'uuid', nullable: true })
+  impersonatorId: string;
+
+  @Index()
+  @Column({ name: 'action', type: 'varchar', length: 50 })
+  action: AuditAction;
+
+  @Index()
+  @Column({ name: 'action_category', type: 'varchar', length: 50, nullable: true })
+  actionCategory: AuditCategory;
+
+  @Index()
+  @Column({ name: 'resource_type', type: 'varchar', length: 100 })
+  resourceType: string;
+
+  @Column({ name: 'resource_id', type: 'uuid', nullable: true })
+  resourceId: string;
+
+  @Column({ name: 'resource_name', type: 'varchar', length: 255, nullable: true })
+  resourceName: string;
+
+  @Column({ name: 'old_values', type: 'jsonb', nullable: true })
+  oldValues: Record<string, any>;
+
+  @Column({ name: 'new_values', type: 'jsonb', nullable: true })
+  newValues: Record<string, any>;
+
+  @Column({ name: 'changed_fields', type: 'text', array: true, nullable: true })
+  changedFields: string[];
+
+  @Column({ name: 'ip_address', type: 'inet', nullable: true })
+  ipAddress: string;
+
+  @Column({ name: 'user_agent', type: 'text', nullable: true })
+  userAgent: string;
+
+  @Column({ name: 'device_info', type: 'jsonb', default: {} })
+  deviceInfo: Record<string, any>;
+
+  @Column({ name: 'location', type: 'jsonb', default: {} })
+  location: Record<string, any>;
+
+  @Column({ name: 'request_id', type: 'varchar', length: 100, nullable: true })
+  requestId: string;
+
+  @Column({ name: 'request_method', type: 'varchar', length: 10, nullable: true })
+  requestMethod: string;
+
+  @Column({ name: 'request_path', type: 'text', nullable: true })
+  requestPath: string;
+
+  @Column({ name: 'request_params', type: 'jsonb', default: {} })
+  requestParams: Record<string, any>;
+
+  @Index()
+  @Column({ name: 'status', type: 'varchar', length: 20, default: 'success' })
+  status: AuditStatus;
+
+  @Column({ name: 'error_message', type: 'text', nullable: true })
+  errorMessage: string;
+
+  @Column({ name: 'duration_ms', type: 'int', nullable: true })
+  durationMs: number;
+
+  @Column({ name: 'metadata', type: 'jsonb', default: {} })
+  metadata: Record<string, any>;
+
+  @Column({ name: 'tags', type: 'text', array: true, default: [] })
+  tags: string[];
+
+  @Index()
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+}
--- a/src/modules/audit/entities/config-change.entity.ts
+++ b/src/modules/audit/entities/config-change.entity.ts
@ -0,0 +1,55 @@
+/**
+ * ConfigChange Entity
+ * System configuration change auditing
+ * Compatible with erp-core config-change.entity
+ *
+ * @module Audit
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  Index,
+} from 'typeorm';
+
+export type ConfigType = 'tenant_settings' | 'user_settings' | 'system_settings' | 'feature_flags';
+
+@Entity({ name: 'config_changes', schema: 'audit' })
+export class ConfigChange {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid', nullable: true })
+  tenantId: string;
+
+  @Column({ name: 'changed_by', type: 'uuid' })
+  changedBy: string;
+
+  @Index()
+  @Column({ name: 'config_type', type: 'varchar', length: 50 })
+  configType: ConfigType;
+
+  @Column({ name: 'config_key', type: 'varchar', length: 100 })
+  configKey: string;
+
+  @Column({ name: 'config_path', type: 'text', nullable: true })
+  configPath: string;
+
+  @Column({ name: 'old_value', type: 'jsonb', nullable: true })
+  oldValue: Record<string, any>;
+
+  @Column({ name: 'new_value', type: 'jsonb', nullable: true })
+  newValue: Record<string, any>;
+
+  @Column({ name: 'reason', type: 'text', nullable: true })
+  reason: string;
+
+  @Column({ name: 'ticket_id', type: 'varchar', length: 50, nullable: true })
+  ticketId: string;
+
+  @Index()
+  @Column({ name: 'changed_at', type: 'timestamptz', default: () => 'CURRENT_TIMESTAMP' })
+  changedAt: Date;
+}
--- a/src/modules/audit/entities/data-export.entity.ts
+++ b/src/modules/audit/entities/data-export.entity.ts
@ -0,0 +1,88 @@
+/**
+ * DataExport Entity
+ * GDPR/reporting data export request management
+ * Compatible with erp-core data-export.entity
+ *
+ * @module Audit
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  Index,
+} from 'typeorm';
+
+export type ExportType = 'report' | 'backup' | 'gdpr_request' | 'bulk_export';
+export type ExportFormat = 'csv' | 'xlsx' | 'pdf' | 'json';
+export type ExportStatus = 'pending' | 'processing' | 'completed' | 'failed' | 'expired';
+
+@Entity({ name: 'data_exports', schema: 'audit' })
+export class DataExport {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Index()
+  @Column({ name: 'user_id', type: 'uuid' })
+  userId: string;
+
+  @Column({ name: 'export_type', type: 'varchar', length: 50 })
+  exportType: ExportType;
+
+  @Column({ name: 'export_format', type: 'varchar', length: 20, nullable: true })
+  exportFormat: ExportFormat;
+
+  @Column({ name: 'entity_types', type: 'text', array: true })
+  entityTypes: string[];
+
+  @Column({ name: 'filters', type: 'jsonb', default: {} })
+  filters: Record<string, any>;
+
+  @Column({ name: 'date_range_start', type: 'timestamptz', nullable: true })
+  dateRangeStart: Date;
+
+  @Column({ name: 'date_range_end', type: 'timestamptz', nullable: true })
+  dateRangeEnd: Date;
+
+  @Column({ name: 'record_count', type: 'int', nullable: true })
+  recordCount: number;
+
+  @Column({ name: 'file_size_bytes', type: 'bigint', nullable: true })
+  fileSizeBytes: number;
+
+  @Column({ name: 'file_hash', type: 'varchar', length: 64, nullable: true })
+  fileHash: string;
+
+  @Index()
+  @Column({ name: 'status', type: 'varchar', length: 20, default: 'pending' })
+  status: ExportStatus;
+
+  @Column({ name: 'download_url', type: 'text', nullable: true })
+  downloadUrl: string;
+
+  @Column({ name: 'download_expires_at', type: 'timestamptz', nullable: true })
+  downloadExpiresAt: Date;
+
+  @Column({ name: 'download_count', type: 'int', default: 0 })
+  downloadCount: number;
+
+  @Column({ name: 'ip_address', type: 'inet', nullable: true })
+  ipAddress: string;
+
+  @Column({ name: 'user_agent', type: 'text', nullable: true })
+  userAgent: string;
+
+  @Index()
+  @Column({ name: 'requested_at', type: 'timestamptz', default: () => 'CURRENT_TIMESTAMP' })
+  requestedAt: Date;
+
+  @Column({ name: 'completed_at', type: 'timestamptz', nullable: true })
+  completedAt: Date;
+
+  @Column({ name: 'expires_at', type: 'timestamptz', nullable: true })
+  expiresAt: Date;
+}
--- a/src/modules/audit/entities/entity-change.entity.ts
+++ b/src/modules/audit/entities/entity-change.entity.ts
@ -0,0 +1,63 @@
+/**
+ * EntityChange Entity
+ * Data modification versioning and change history
+ * Compatible with erp-core entity-change.entity
+ *
+ * @module Audit
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  Index,
+} from 'typeorm';
+
+export type ChangeType = 'create' | 'update' | 'delete' | 'restore';
+
+@Entity({ name: 'entity_changes', schema: 'audit' })
+export class EntityChange {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Index()
+  @Column({ name: 'entity_type', type: 'varchar', length: 100 })
+  entityType: string;
+
+  @Index()
+  @Column({ name: 'entity_id', type: 'uuid' })
+  entityId: string;
+
+  @Column({ name: 'entity_name', type: 'varchar', length: 255, nullable: true })
+  entityName: string;
+
+  @Column({ name: 'version', type: 'int', default: 1 })
+  version: number;
+
+  @Column({ name: 'previous_version', type: 'int', nullable: true })
+  previousVersion: number;
+
+  @Column({ name: 'data_snapshot', type: 'jsonb' })
+  dataSnapshot: Record<string, any>;
+
+  @Column({ name: 'changes', type: 'jsonb', default: [] })
+  changes: Record<string, any>[];
+
+  @Index()
+  @Column({ name: 'changed_by', type: 'uuid', nullable: true })
+  changedBy: string;
+
+  @Column({ name: 'change_reason', type: 'text', nullable: true })
+  changeReason: string;
+
+  @Column({ name: 'change_type', type: 'varchar', length: 20 })
+  changeType: ChangeType;
+
+  @Index()
+  @Column({ name: 'changed_at', type: 'timestamptz', default: () => 'CURRENT_TIMESTAMP' })
+  changedAt: Date;
+}
--- a/src/modules/audit/entities/index.ts
+++ b/src/modules/audit/entities/index.ts
@ -0,0 +1,11 @@
+/**
+ * Audit Entities - Export
+ */
+
+export { AuditLog, AuditAction, AuditCategory, AuditStatus } from './audit-log.entity';
+export { EntityChange, ChangeType } from './entity-change.entity';
+export { LoginHistory, LoginStatus, AuthMethod, MfaMethod } from './login-history.entity';
+export { SensitiveDataAccess, DataType, AccessType } from './sensitive-data-access.entity';
+export { DataExport, ExportType, ExportFormat, ExportStatus } from './data-export.entity';
+export { PermissionChange, PermissionChangeType, PermissionScope } from './permission-change.entity';
+export { ConfigChange, ConfigType } from './config-change.entity';
--- a/src/modules/audit/entities/login-history.entity.ts
+++ b/src/modules/audit/entities/login-history.entity.ts
@ -0,0 +1,114 @@
+/**
+ * LoginHistory Entity
+ * Authentication event tracking with device, location and risk scoring
+ * Compatible with erp-core login-history.entity
+ *
+ * @module Audit
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  Index,
+} from 'typeorm';
+
+export type LoginStatus = 'success' | 'failed' | 'blocked' | 'mfa_required' | 'mfa_failed';
+export type AuthMethod = 'password' | 'sso' | 'oauth' | 'mfa' | 'magic_link' | 'biometric';
+export type MfaMethod = 'totp' | 'sms' | 'email' | 'push';
+
+@Entity({ name: 'login_history', schema: 'audit' })
+export class LoginHistory {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid', nullable: true })
+  tenantId: string;
+
+  @Index()
+  @Column({ name: 'user_id', type: 'uuid', nullable: true })
+  userId: string;
+
+  @Column({ name: 'email', type: 'varchar', length: 255, nullable: true })
+  email: string;
+
+  @Column({ name: 'username', type: 'varchar', length: 100, nullable: true })
+  username: string;
+
+  @Index()
+  @Column({ name: 'status', type: 'varchar', length: 20 })
+  status: LoginStatus;
+
+  @Column({ name: 'auth_method', type: 'varchar', length: 30, nullable: true })
+  authMethod: AuthMethod;
+
+  @Column({ name: 'oauth_provider', type: 'varchar', length: 30, nullable: true })
+  oauthProvider: string;
+
+  @Column({ name: 'mfa_method', type: 'varchar', length: 20, nullable: true })
+  mfaMethod: MfaMethod;
+
+  @Column({ name: 'mfa_verified', type: 'boolean', nullable: true })
+  mfaVerified: boolean;
+
+  @Column({ name: 'device_id', type: 'uuid', nullable: true })
+  deviceId: string;
+
+  @Column({ name: 'device_fingerprint', type: 'varchar', length: 255, nullable: true })
+  deviceFingerprint: string;
+
+  @Column({ name: 'device_type', type: 'varchar', length: 30, nullable: true })
+  deviceType: string;
+
+  @Column({ name: 'device_os', type: 'varchar', length: 50, nullable: true })
+  deviceOs: string;
+
+  @Column({ name: 'device_browser', type: 'varchar', length: 50, nullable: true })
+  deviceBrowser: string;
+
+  @Index()
+  @Column({ name: 'ip_address', type: 'inet', nullable: true })
+  ipAddress: string;
+
+  @Column({ name: 'user_agent', type: 'text', nullable: true })
+  userAgent: string;
+
+  @Column({ name: 'country_code', type: 'varchar', length: 2, nullable: true })
+  countryCode: string;
+
+  @Column({ name: 'city', type: 'varchar', length: 100, nullable: true })
+  city: string;
+
+  @Column({ name: 'latitude', type: 'decimal', precision: 10, scale: 8, nullable: true })
+  latitude: number;
+
+  @Column({ name: 'longitude', type: 'decimal', precision: 11, scale: 8, nullable: true })
+  longitude: number;
+
+  @Column({ name: 'risk_score', type: 'int', nullable: true })
+  riskScore: number;
+
+  @Column({ name: 'risk_factors', type: 'jsonb', default: [] })
+  riskFactors: string[];
+
+  @Index()
+  @Column({ name: 'is_suspicious', type: 'boolean', default: false })
+  isSuspicious: boolean;
+
+  @Column({ name: 'is_new_device', type: 'boolean', default: false })
+  isNewDevice: boolean;
+
+  @Column({ name: 'is_new_location', type: 'boolean', default: false })
+  isNewLocation: boolean;
+
+  @Column({ name: 'failure_reason', type: 'varchar', length: 100, nullable: true })
+  failureReason: string;
+
+  @Column({ name: 'failure_count', type: 'int', nullable: true })
+  failureCount: number;
+
+  @Index()
+  @Column({ name: 'attempted_at', type: 'timestamptz', default: () => 'CURRENT_TIMESTAMP' })
+  attemptedAt: Date;
+}
--- a/src/modules/audit/entities/permission-change.entity.ts
+++ b/src/modules/audit/entities/permission-change.entity.ts
@ -0,0 +1,71 @@
+/**
+ * PermissionChange Entity
+ * Access control change auditing
+ * Compatible with erp-core permission-change.entity
+ *
+ * @module Audit
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  Index,
+} from 'typeorm';
+
+export type PermissionChangeType = 'role_assigned' | 'role_revoked' | 'permission_granted' | 'permission_revoked';
+export type PermissionScope = 'global' | 'tenant' | 'branch';
+
+@Entity({ name: 'permission_changes', schema: 'audit' })
+export class PermissionChange {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Column({ name: 'changed_by', type: 'uuid' })
+  changedBy: string;
+
+  @Index()
+  @Column({ name: 'target_user_id', type: 'uuid' })
+  targetUserId: string;
+
+  @Column({ name: 'target_user_email', type: 'varchar', length: 255, nullable: true })
+  targetUserEmail: string;
+
+  @Column({ name: 'change_type', type: 'varchar', length: 30 })
+  changeType: PermissionChangeType;
+
+  @Column({ name: 'role_id', type: 'uuid', nullable: true })
+  roleId: string;
+
+  @Column({ name: 'role_code', type: 'varchar', length: 50, nullable: true })
+  roleCode: string;
+
+  @Column({ name: 'permission_id', type: 'uuid', nullable: true })
+  permissionId: string;
+
+  @Column({ name: 'permission_code', type: 'varchar', length: 100, nullable: true })
+  permissionCode: string;
+
+  @Column({ name: 'branch_id', type: 'uuid', nullable: true })
+  branchId: string;
+
+  @Column({ name: 'scope', type: 'varchar', length: 30, nullable: true })
+  scope: PermissionScope;
+
+  @Column({ name: 'previous_roles', type: 'text', array: true, nullable: true })
+  previousRoles: string[];
+
+  @Column({ name: 'previous_permissions', type: 'text', array: true, nullable: true })
+  previousPermissions: string[];
+
+  @Column({ name: 'reason', type: 'text', nullable: true })
+  reason: string;
+
+  @Index()
+  @Column({ name: 'changed_at', type: 'timestamptz', default: () => 'CURRENT_TIMESTAMP' })
+  changedAt: Date;
+}
--- a/src/modules/audit/entities/sensitive-data-access.entity.ts
+++ b/src/modules/audit/entities/sensitive-data-access.entity.ts
@ -0,0 +1,70 @@
+/**
+ * SensitiveDataAccess Entity
+ * Security/compliance logging for PII, financial, medical and credential access
+ * Compatible with erp-core sensitive-data-access.entity
+ *
+ * @module Audit
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  Index,
+} from 'typeorm';
+
+export type DataType = 'pii' | 'financial' | 'medical' | 'credentials';
+export type AccessType = 'view' | 'export' | 'modify' | 'decrypt';
+
+@Entity({ name: 'sensitive_data_access', schema: 'audit' })
+export class SensitiveDataAccess {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Index()
+  @Column({ name: 'user_id', type: 'uuid' })
+  userId: string;
+
+  @Column({ name: 'session_id', type: 'uuid', nullable: true })
+  sessionId: string;
+
+  @Index()
+  @Column({ name: 'data_type', type: 'varchar', length: 100 })
+  dataType: DataType;
+
+  @Column({ name: 'data_category', type: 'varchar', length: 100, nullable: true })
+  dataCategory: string;
+
+  @Column({ name: 'entity_type', type: 'varchar', length: 100, nullable: true })
+  entityType: string;
+
+  @Column({ name: 'entity_id', type: 'uuid', nullable: true })
+  entityId: string;
+
+  @Column({ name: 'access_type', type: 'varchar', length: 30 })
+  accessType: AccessType;
+
+  @Column({ name: 'access_reason', type: 'text', nullable: true })
+  accessReason: string;
+
+  @Column({ name: 'ip_address', type: 'inet', nullable: true })
+  ipAddress: string;
+
+  @Column({ name: 'user_agent', type: 'text', nullable: true })
+  userAgent: string;
+
+  @Index()
+  @Column({ name: 'was_authorized', type: 'boolean', default: true })
+  wasAuthorized: boolean;
+
+  @Column({ name: 'denial_reason', type: 'text', nullable: true })
+  denialReason: string;
+
+  @Index()
+  @Column({ name: 'accessed_at', type: 'timestamptz', default: () => 'CURRENT_TIMESTAMP' })
+  accessedAt: Date;
+}
--- a/src/modules/billing-usage/entities/billing-alert.entity.ts
+++ b/src/modules/billing-usage/entities/billing-alert.entity.ts
@ -0,0 +1,72 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+} from 'typeorm';
+
+export type BillingAlertType =
+  | 'usage_limit'
+  | 'payment_due'
+  | 'payment_failed'
+  | 'trial_ending'
+  | 'subscription_ending';
+
+export type AlertSeverity = 'info' | 'warning' | 'critical';
+export type AlertStatus = 'active' | 'acknowledged' | 'resolved';
+
+/**
+ * Entidad para alertas de facturacion y limites de uso.
+ * Mapea a billing.billing_alerts (DDL: 05-billing-usage.sql)
+ */
+@Entity({ name: 'billing_alerts', schema: 'billing' })
+export class BillingAlert {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  // Tipo de alerta
+  @Index()
+  @Column({ name: 'alert_type', type: 'varchar', length: 30 })
+  alertType: BillingAlertType;
+
+  // Detalles
+  @Column({ type: 'varchar', length: 200 })
+  title: string;
+
+  @Column({ type: 'text', nullable: true })
+  message: string;
+
+  @Column({ type: 'varchar', length: 20, default: 'info' })
+  severity: AlertSeverity;
+
+  // Estado
+  @Index()
+  @Column({ type: 'varchar', length: 20, default: 'active' })
+  status: AlertStatus;
+
+  // Notificacion
+  @Column({ name: 'notified_at', type: 'timestamptz', nullable: true })
+  notifiedAt: Date;
+
+  @Column({ name: 'acknowledged_at', type: 'timestamptz', nullable: true })
+  acknowledgedAt: Date;
+
+  @Column({ name: 'acknowledged_by', type: 'uuid', nullable: true })
+  acknowledgedBy: string;
+
+  // Metadata
+  @Column({ type: 'jsonb', default: {} })
+  metadata: Record<string, any>;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+}
--- a/src/modules/billing-usage/entities/coupon-redemption.entity.ts
+++ b/src/modules/billing-usage/entities/coupon-redemption.entity.ts
@ -0,0 +1,44 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  ManyToOne,
+  JoinColumn,
+  CreateDateColumn,
+  Unique,
+} from 'typeorm';
+import { Coupon } from './coupon.entity';
+import { TenantSubscription } from './tenant-subscription.entity';
+
+@Entity({ name: 'coupon_redemptions', schema: 'billing' })
+@Unique(['couponId', 'tenantId'])
+export class CouponRedemption {
+  @PrimaryGeneratedColumn('uuid')
+  id!: string;
+
+  @Column({ name: 'coupon_id', type: 'uuid' })
+  couponId!: string;
+
+  @ManyToOne(() => Coupon, (coupon) => coupon.redemptions)
+  @JoinColumn({ name: 'coupon_id' })
+  coupon!: Coupon;
+
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId!: string;
+
+  @Column({ name: 'subscription_id', type: 'uuid', nullable: true })
+  subscriptionId?: string;
+
+  @ManyToOne(() => TenantSubscription, { nullable: true })
+  @JoinColumn({ name: 'subscription_id' })
+  subscription?: TenantSubscription;
+
+  @Column({ name: 'discount_amount', type: 'decimal', precision: 10, scale: 2 })
+  discountAmount!: number;
+
+  @CreateDateColumn({ name: 'redeemed_at', type: 'timestamptz' })
+  redeemedAt!: Date;
+
+  @Column({ name: 'expires_at', type: 'timestamptz', nullable: true })
+  expiresAt?: Date;
+}
--- a/src/modules/billing-usage/entities/coupon.entity.ts
+++ b/src/modules/billing-usage/entities/coupon.entity.ts
@ -0,0 +1,72 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  OneToMany,
+} from 'typeorm';
+import { CouponRedemption } from './coupon-redemption.entity';
+
+export type DiscountType = 'percentage' | 'fixed';
+export type DurationPeriod = 'once' | 'forever' | 'months';
+
+@Entity({ name: 'coupons', schema: 'billing' })
+export class Coupon {
+  @PrimaryGeneratedColumn('uuid')
+  id!: string;
+
+  @Column({ type: 'varchar', length: 50, unique: true })
+  code!: string;
+
+  @Column({ type: 'varchar', length: 255 })
+  name!: string;
+
+  @Column({ type: 'text', nullable: true })
+  description?: string;
+
+  @Column({ name: 'discount_type', type: 'varchar', length: 20 })
+  discountType!: DiscountType;
+
+  @Column({ name: 'discount_value', type: 'decimal', precision: 10, scale: 2 })
+  discountValue!: number;
+
+  @Column({ type: 'varchar', length: 3, default: 'MXN' })
+  currency!: string;
+
+  @Column({ name: 'applicable_plans', type: 'uuid', array: true, default: [] })
+  applicablePlans!: string[];
+
+  @Column({ name: 'min_amount', type: 'decimal', precision: 10, scale: 2, default: 0 })
+  minAmount!: number;
+
+  @Column({ name: 'duration_period', type: 'varchar', length: 20, default: 'once' })
+  durationPeriod!: DurationPeriod;
+
+  @Column({ name: 'duration_months', type: 'integer', nullable: true })
+  durationMonths?: number;
+
+  @Column({ name: 'max_redemptions', type: 'integer', nullable: true })
+  maxRedemptions?: number;
+
+  @Column({ name: 'current_redemptions', type: 'integer', default: 0 })
+  currentRedemptions!: number;
+
+  @Column({ name: 'valid_from', type: 'timestamptz', nullable: true })
+  validFrom?: Date;
+
+  @Column({ name: 'valid_until', type: 'timestamptz', nullable: true })
+  validUntil?: Date;
+
+  @Column({ name: 'is_active', type: 'boolean', default: true })
+  isActive!: boolean;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt!: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt!: Date;
+
+  @OneToMany(() => CouponRedemption, (redemption) => redemption.coupon)
+  redemptions!: CouponRedemption[];
+}
--- a/src/modules/billing-usage/entities/index.ts
+++ b/src/modules/billing-usage/entities/index.ts
@ -0,0 +1,13 @@
+export { SubscriptionPlan, PlanType } from './subscription-plan.entity';
+export { TenantSubscription, BillingCycle, SubscriptionStatus } from './tenant-subscription.entity';
+export { UsageTracking } from './usage-tracking.entity';
+export { UsageEvent, EventCategory } from './usage-event.entity';
+export { Invoice, InvoiceStatus, InvoiceContext, InvoiceType, InvoiceItem } from './invoice.entity';
+export { InvoiceItemType } from './invoice-item.entity';
+export { BillingPaymentMethod, PaymentProvider, PaymentMethodType } from './payment-method.entity';
+export { BillingAlert, BillingAlertType, AlertSeverity, AlertStatus } from './billing-alert.entity';
+export { PlanFeature } from './plan-feature.entity';
+export { PlanLimit, LimitType } from './plan-limit.entity';
+export { Coupon, DiscountType, DurationPeriod } from './coupon.entity';
+export { CouponRedemption } from './coupon-redemption.entity';
+export { StripeEvent } from './stripe-event.entity';
--- a/src/modules/billing-usage/entities/invoice-item.entity.ts
+++ b/src/modules/billing-usage/entities/invoice-item.entity.ts
@ -0,0 +1,65 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { Invoice } from '../../invoices/entities/invoice.entity';
+
+export type InvoiceItemType = 'subscription' | 'user' | 'profile' | 'overage' | 'addon';
+
+@Entity({ name: 'invoice_items', schema: 'billing' })
+export class InvoiceItem {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'invoice_id', type: 'uuid' })
+  invoiceId: string;
+
+  // Descripcion
+  @Column({ type: 'varchar', length: 500 })
+  description: string;
+
+  @Index()
+  @Column({ name: 'item_type', type: 'varchar', length: 30 })
+  itemType: InvoiceItemType;
+
+  // Cantidades
+  @Column({ type: 'integer', default: 1 })
+  quantity: number;
+
+  @Column({ name: 'unit_price', type: 'decimal', precision: 12, scale: 2 })
+  unitPrice: number;
+
+  @Column({ type: 'decimal', precision: 12, scale: 2 })
+  subtotal: number;
+
+  // Detalles adicionales
+  @Column({ name: 'profile_code', type: 'varchar', length: 10, nullable: true })
+  profileCode: string;
+
+  @Column({ type: 'varchar', length: 20, nullable: true })
+  platform: string;
+
+  @Column({ name: 'period_start', type: 'date', nullable: true })
+  periodStart: Date;
+
+  @Column({ name: 'period_end', type: 'date', nullable: true })
+  periodEnd: Date;
+
+  // Metadata
+  @Column({ type: 'jsonb', default: {} })
+  metadata: Record<string, any>;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  // Relaciones
+  @ManyToOne(() => Invoice, (invoice) => invoice.items, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'invoice_id' })
+  invoice: Invoice;
+}
--- a/src/modules/billing-usage/entities/invoice.entity.ts
+++ b/src/modules/billing-usage/entities/invoice.entity.ts
@ -0,0 +1,17 @@
+/**
+ * @deprecated Use Invoice from 'modules/invoices/entities' instead.
+ *
+ * This entity has been unified with the commercial Invoice entity.
+ * Both SaaS billing and commercial invoices now use the same table.
+ *
+ * Migration guide:
+ * - Import from: import { Invoice, InvoiceStatus, InvoiceContext } from '../../invoices/entities/invoice.entity';
+ * - Set invoiceContext: 'saas' for SaaS billing invoices
+ * - Use subscriptionId, periodStart, periodEnd for SaaS-specific fields
+ */
+
+// Re-export from unified invoice entity
+export { Invoice, InvoiceStatus, InvoiceContext, InvoiceType } from '../../invoices/entities/invoice.entity';
+
+// Re-export InvoiceItem as well since it's used together
+export { InvoiceItem } from './invoice-item.entity';
--- a/src/modules/billing-usage/entities/payment-method.entity.ts
+++ b/src/modules/billing-usage/entities/payment-method.entity.ts
@ -0,0 +1,85 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  DeleteDateColumn,
+  Index,
+} from 'typeorm';
+
+export type PaymentProvider = 'stripe' | 'mercadopago' | 'bank_transfer';
+export type PaymentMethodType = 'card' | 'bank_account' | 'wallet';
+
+/**
+ * Entidad para metodos de pago guardados por tenant.
+ * Almacena informacion tokenizada/encriptada de metodos de pago.
+ * Mapea a billing.payment_methods (DDL: 05-billing-usage.sql)
+ */
+@Entity({ name: 'payment_methods', schema: 'billing' })
+export class BillingPaymentMethod {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  // Proveedor
+  @Index()
+  @Column({ type: 'varchar', length: 30 })
+  provider: PaymentProvider;
+
+  // Tipo
+  @Column({ name: 'method_type', type: 'varchar', length: 20 })
+  methodType: PaymentMethodType;
+
+  // Datos tokenizados del proveedor
+  @Column({ name: 'provider_customer_id', type: 'varchar', length: 255, nullable: true })
+  providerCustomerId: string;
+
+  @Column({ name: 'provider_method_id', type: 'varchar', length: 255, nullable: true })
+  providerMethodId: string;
+
+  // Display info (no sensible)
+  @Column({ name: 'display_name', type: 'varchar', length: 100, nullable: true })
+  displayName: string;
+
+  @Column({ name: 'card_brand', type: 'varchar', length: 20, nullable: true })
+  cardBrand: string;
+
+  @Column({ name: 'card_last_four', type: 'varchar', length: 4, nullable: true })
+  cardLastFour: string;
+
+  @Column({ name: 'card_exp_month', type: 'integer', nullable: true })
+  cardExpMonth: number;
+
+  @Column({ name: 'card_exp_year', type: 'integer', nullable: true })
+  cardExpYear: number;
+
+  @Column({ name: 'bank_name', type: 'varchar', length: 100, nullable: true })
+  bankName: string;
+
+  @Column({ name: 'bank_last_four', type: 'varchar', length: 4, nullable: true })
+  bankLastFour: string;
+
+  // Estado
+  @Index()
+  @Column({ name: 'is_default', type: 'boolean', default: false })
+  isDefault: boolean;
+
+  @Column({ name: 'is_active', type: 'boolean', default: true })
+  isActive: boolean;
+
+  @Column({ name: 'is_verified', type: 'boolean', default: false })
+  isVerified: boolean;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+
+  @DeleteDateColumn({ name: 'deleted_at', type: 'timestamptz', nullable: true })
+  deletedAt: Date;
+}
--- a/src/modules/billing-usage/entities/plan-feature.entity.ts
+++ b/src/modules/billing-usage/entities/plan-feature.entity.ts
@ -0,0 +1,61 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { SubscriptionPlan } from './subscription-plan.entity';
+
+/**
+ * PlanFeature Entity
+ * Maps to billing.plan_features DDL table
+ * Features disponibles por plan de suscripcion
+ * Propagated from template-saas HU-REFACT-005
+ */
+@Entity({ schema: 'billing', name: 'plan_features' })
+@Index('idx_plan_features_plan', ['planId'])
+@Index('idx_plan_features_key', ['featureKey'])
+export class PlanFeature {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'uuid', nullable: false, name: 'plan_id' })
+  planId: string;
+
+  @Column({ type: 'varchar', length: 100, nullable: false, name: 'feature_key' })
+  featureKey: string;
+
+  @Column({ type: 'varchar', length: 255, nullable: false, name: 'feature_name' })
+  featureName: string;
+
+  @Column({ type: 'varchar', length: 100, nullable: true })
+  category: string | null;
+
+  @Column({ type: 'boolean', default: true })
+  enabled: boolean;
+
+  @Column({ type: 'jsonb', default: {} })
+  configuration: Record<string, any>;
+
+  @Column({ type: 'text', nullable: true })
+  description: string | null;
+
+  @Column({ type: 'jsonb', default: {} })
+  metadata: Record<string, any>;
+
+  // Relaciones
+  @ManyToOne(() => SubscriptionPlan, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'plan_id' })
+  plan: SubscriptionPlan;
+
+  // Timestamps
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+}
--- a/src/modules/billing-usage/entities/plan-limit.entity.ts
+++ b/src/modules/billing-usage/entities/plan-limit.entity.ts
@ -0,0 +1,52 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  ManyToOne,
+  JoinColumn,
+  CreateDateColumn,
+  UpdateDateColumn,
+} from 'typeorm';
+import { SubscriptionPlan } from './subscription-plan.entity';
+
+export type LimitType = 'monthly' | 'daily' | 'total' | 'per_user';
+
+@Entity({ name: 'plan_limits', schema: 'billing' })
+export class PlanLimit {
+  @PrimaryGeneratedColumn('uuid')
+  id!: string;
+
+  @Column({ name: 'plan_id', type: 'uuid' })
+  planId!: string;
+
+  @ManyToOne(() => SubscriptionPlan, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'plan_id' })
+  plan!: SubscriptionPlan;
+
+  @Column({ name: 'limit_key', type: 'varchar', length: 100 })
+  limitKey!: string;
+
+  @Column({ name: 'limit_name', type: 'varchar', length: 255 })
+  limitName!: string;
+
+  @Column({ name: 'limit_value', type: 'integer' })
+  limitValue!: number;
+
+  @Column({ name: 'limit_type', type: 'varchar', length: 50, default: 'monthly' })
+  limitType!: LimitType;
+
+  @Column({ name: 'allow_overage', type: 'boolean', default: false })
+  allowOverage!: boolean;
+
+  @Column({ name: 'overage_unit_price', type: 'decimal', precision: 10, scale: 4, default: 0 })
+  overageUnitPrice!: number;
+
+  @Column({ name: 'overage_currency', type: 'varchar', length: 3, default: 'MXN' })
+  overageCurrency!: string;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt!: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt!: Date;
+}
--- a/src/modules/billing-usage/entities/stripe-event.entity.ts
+++ b/src/modules/billing-usage/entities/stripe-event.entity.ts
@ -0,0 +1,43 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  Index,
+} from 'typeorm';
+
+@Entity({ name: 'stripe_events', schema: 'billing' })
+export class StripeEvent {
+  @PrimaryGeneratedColumn('uuid')
+  id!: string;
+
+  @Column({ name: 'stripe_event_id', type: 'varchar', length: 255, unique: true })
+  @Index()
+  stripeEventId!: string;
+
+  @Column({ name: 'event_type', type: 'varchar', length: 100 })
+  @Index()
+  eventType!: string;
+
+  @Column({ name: 'api_version', type: 'varchar', length: 20, nullable: true })
+  apiVersion?: string;
+
+  @Column({ type: 'jsonb' })
+  data!: Record<string, any>;
+
+  @Column({ type: 'boolean', default: false })
+  @Index()
+  processed!: boolean;
+
+  @Column({ name: 'processed_at', type: 'timestamptz', nullable: true })
+  processedAt?: Date;
+
+  @Column({ name: 'error_message', type: 'text', nullable: true })
+  errorMessage?: string;
+
+  @Column({ name: 'retry_count', type: 'integer', default: 0 })
+  retryCount!: number;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt!: Date;
+}
--- a/src/modules/billing-usage/entities/subscription-plan.entity.ts
+++ b/src/modules/billing-usage/entities/subscription-plan.entity.ts
@ -0,0 +1,83 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  DeleteDateColumn,
+  Index,
+} from 'typeorm';
+
+export type PlanType = 'saas' | 'on_premise' | 'hybrid';
+
+@Entity({ name: 'subscription_plans', schema: 'billing' })
+export class SubscriptionPlan {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  // Identificacion
+  @Index({ unique: true })
+  @Column({ type: 'varchar', length: 30 })
+  code: string;
+
+  @Column({ type: 'varchar', length: 100 })
+  name: string;
+
+  @Column({ type: 'text', nullable: true })
+  description: string;
+
+  // Tipo
+  @Column({ name: 'plan_type', type: 'varchar', length: 20, default: 'saas' })
+  planType: PlanType;
+
+  // Precios base
+  @Column({ name: 'base_monthly_price', type: 'decimal', precision: 12, scale: 2, default: 0 })
+  baseMonthlyPrice: number;
+
+  @Column({ name: 'base_annual_price', type: 'decimal', precision: 12, scale: 2, nullable: true })
+  baseAnnualPrice: number;
+
+  @Column({ name: 'setup_fee', type: 'decimal', precision: 12, scale: 2, default: 0 })
+  setupFee: number;
+
+  // Limites base
+  @Column({ name: 'max_users', type: 'integer', default: 5 })
+  maxUsers: number;
+
+  @Column({ name: 'max_branches', type: 'integer', default: 1 })
+  maxBranches: number;
+
+  @Column({ name: 'storage_gb', type: 'integer', default: 10 })
+  storageGb: number;
+
+  @Column({ name: 'api_calls_monthly', type: 'integer', default: 10000 })
+  apiCallsMonthly: number;
+
+  // Modulos incluidos
+  @Column({ name: 'included_modules', type: 'text', array: true, default: [] })
+  includedModules: string[];
+
+  // Plataformas incluidas
+  @Column({ name: 'included_platforms', type: 'text', array: true, default: ['web'] })
+  includedPlatforms: string[];
+
+  // Features
+  @Column({ type: 'jsonb', default: {} })
+  features: Record<string, boolean>;
+
+  // Estado
+  @Column({ name: 'is_active', type: 'boolean', default: true })
+  isActive: boolean;
+
+  @Column({ name: 'is_public', type: 'boolean', default: true })
+  isPublic: boolean;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+
+  @DeleteDateColumn({ name: 'deleted_at', type: 'timestamptz', nullable: true })
+  deletedAt: Date;
+}
--- a/src/modules/billing-usage/entities/tenant-subscription.entity.ts
+++ b/src/modules/billing-usage/entities/tenant-subscription.entity.ts
@ -0,0 +1,132 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+  Unique,
+} from 'typeorm';
+import { SubscriptionPlan } from './subscription-plan.entity';
+
+export type BillingCycle = 'monthly' | 'annual';
+export type SubscriptionStatus = 'trial' | 'active' | 'past_due' | 'cancelled' | 'suspended';
+
+@Entity({ name: 'tenant_subscriptions', schema: 'billing' })
+@Unique(['tenantId'])
+export class TenantSubscription {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Index()
+  @Column({ name: 'plan_id', type: 'uuid' })
+  planId: string;
+
+  // Periodo
+  @Column({ name: 'billing_cycle', type: 'varchar', length: 20, default: 'monthly' })
+  billingCycle: BillingCycle;
+
+  @Column({ name: 'current_period_start', type: 'timestamptz' })
+  currentPeriodStart: Date;
+
+  @Column({ name: 'current_period_end', type: 'timestamptz' })
+  currentPeriodEnd: Date;
+
+  // Estado
+  @Index()
+  @Column({ type: 'varchar', length: 20, default: 'active' })
+  status: SubscriptionStatus;
+
+  // Trial
+  @Column({ name: 'trial_start', type: 'timestamptz', nullable: true })
+  trialStart: Date;
+
+  @Column({ name: 'trial_end', type: 'timestamptz', nullable: true })
+  trialEnd: Date;
+
+  // Configuracion de facturacion
+  @Column({ name: 'billing_email', type: 'varchar', length: 255, nullable: true })
+  billingEmail: string;
+
+  @Column({ name: 'billing_name', type: 'varchar', length: 200, nullable: true })
+  billingName: string;
+
+  @Column({ name: 'billing_address', type: 'jsonb', default: {} })
+  billingAddress: Record<string, any>;
+
+  @Column({ name: 'tax_id', type: 'varchar', length: 20, nullable: true })
+  taxId: string; // RFC para Mexico
+
+  // Metodo de pago
+  @Column({ name: 'payment_method_id', type: 'uuid', nullable: true })
+  paymentMethodId: string;
+
+  @Column({ name: 'payment_provider', type: 'varchar', length: 30, nullable: true })
+  paymentProvider: string; // stripe, mercadopago, bank_transfer
+
+  // Stripe integration
+  @Index()
+  @Column({ name: 'stripe_customer_id', type: 'varchar', length: 255, nullable: true })
+  stripeCustomerId?: string;
+
+  @Index()
+  @Column({ name: 'stripe_subscription_id', type: 'varchar', length: 255, nullable: true })
+  stripeSubscriptionId?: string;
+
+  @Column({ name: 'last_payment_at', type: 'timestamptz', nullable: true })
+  lastPaymentAt?: Date;
+
+  @Column({ name: 'last_payment_amount', type: 'decimal', precision: 12, scale: 2, nullable: true })
+  lastPaymentAmount?: number;
+
+  // Precios actuales
+  @Column({ name: 'current_price', type: 'decimal', precision: 12, scale: 2 })
+  currentPrice: number;
+
+  @Column({ name: 'discount_percent', type: 'decimal', precision: 5, scale: 2, default: 0 })
+  discountPercent: number;
+
+  @Column({ name: 'discount_reason', type: 'varchar', length: 100, nullable: true })
+  discountReason: string;
+
+  // Uso contratado
+  @Column({ name: 'contracted_users', type: 'integer', nullable: true })
+  contractedUsers: number;
+
+  @Column({ name: 'contracted_branches', type: 'integer', nullable: true })
+  contractedBranches: number;
+
+  // Facturacion automatica
+  @Column({ name: 'auto_renew', type: 'boolean', default: true })
+  autoRenew: boolean;
+
+  @Column({ name: 'next_invoice_date', type: 'date', nullable: true })
+  nextInvoiceDate: Date;
+
+  // Cancelacion
+  @Column({ name: 'cancel_at_period_end', type: 'boolean', default: false })
+  cancelAtPeriodEnd: boolean;
+
+  @Column({ name: 'cancelled_at', type: 'timestamptz', nullable: true })
+  cancelledAt: Date;
+
+  @Column({ name: 'cancellation_reason', type: 'text', nullable: true })
+  cancellationReason: string;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+
+  // Relaciones
+  @ManyToOne(() => SubscriptionPlan)
+  @JoinColumn({ name: 'plan_id' })
+  plan: SubscriptionPlan;
+}
--- a/src/modules/billing-usage/entities/usage-event.entity.ts
+++ b/src/modules/billing-usage/entities/usage-event.entity.ts
@ -0,0 +1,73 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  Index,
+} from 'typeorm';
+
+export type EventCategory = 'user' | 'api' | 'storage' | 'transaction' | 'mobile';
+
+/**
+ * Entidad para eventos de uso en tiempo real.
+ * Utilizada para calculo de billing y tracking granular.
+ * Mapea a billing.usage_events (DDL: 05-billing-usage.sql)
+ */
+@Entity({ name: 'usage_events', schema: 'billing' })
+export class UsageEvent {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Column({ name: 'user_id', type: 'uuid', nullable: true })
+  userId: string;
+
+  @Column({ name: 'device_id', type: 'uuid', nullable: true })
+  deviceId: string;
+
+  @Column({ name: 'branch_id', type: 'uuid', nullable: true })
+  branchId: string;
+
+  // Evento
+  @Index()
+  @Column({ name: 'event_type', type: 'varchar', length: 50 })
+  eventType: string; // login, api_call, document_upload, sale, invoice, sync
+
+  @Index()
+  @Column({ name: 'event_category', type: 'varchar', length: 30 })
+  eventCategory: EventCategory;
+
+  // Detalles
+  @Column({ name: 'profile_code', type: 'varchar', length: 10, nullable: true })
+  profileCode: string;
+
+  @Column({ type: 'varchar', length: 20, nullable: true })
+  platform: string;
+
+  @Column({ name: 'resource_id', type: 'uuid', nullable: true })
+  resourceId: string;
+
+  @Column({ name: 'resource_type', type: 'varchar', length: 50, nullable: true })
+  resourceType: string;
+
+  // Metricas
+  @Column({ type: 'integer', default: 1 })
+  quantity: number;
+
+  @Column({ name: 'bytes_used', type: 'bigint', default: 0 })
+  bytesUsed: number;
+
+  @Column({ name: 'duration_ms', type: 'integer', nullable: true })
+  durationMs: number;
+
+  // Metadata
+  @Column({ type: 'jsonb', default: {} })
+  metadata: Record<string, any>;
+
+  @Index()
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+}
--- a/src/modules/billing-usage/entities/usage-tracking.entity.ts
+++ b/src/modules/billing-usage/entities/usage-tracking.entity.ts
@ -0,0 +1,91 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  Unique,
+} from 'typeorm';
+
+@Entity({ name: 'usage_tracking', schema: 'billing' })
+@Unique(['tenantId', 'periodStart'])
+export class UsageTracking {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  // Periodo
+  @Index()
+  @Column({ name: 'period_start', type: 'date' })
+  periodStart: Date;
+
+  @Column({ name: 'period_end', type: 'date' })
+  periodEnd: Date;
+
+  // Usuarios
+  @Column({ name: 'active_users', type: 'integer', default: 0 })
+  activeUsers: number;
+
+  @Column({ name: 'peak_concurrent_users', type: 'integer', default: 0 })
+  peakConcurrentUsers: number;
+
+  // Por perfil
+  @Column({ name: 'users_by_profile', type: 'jsonb', default: {} })
+  usersByProfile: Record<string, number>; // {"ADM": 2, "VNT": 5, "ALM": 3}
+
+  // Por plataforma
+  @Column({ name: 'users_by_platform', type: 'jsonb', default: {} })
+  usersByPlatform: Record<string, number>; // {"web": 8, "mobile": 5, "desktop": 0}
+
+  // Sucursales
+  @Column({ name: 'active_branches', type: 'integer', default: 0 })
+  activeBranches: number;
+
+  // Storage
+  @Column({ name: 'storage_used_gb', type: 'decimal', precision: 10, scale: 2, default: 0 })
+  storageUsedGb: number;
+
+  @Column({ name: 'documents_count', type: 'integer', default: 0 })
+  documentsCount: number;
+
+  // API
+  @Column({ name: 'api_calls', type: 'integer', default: 0 })
+  apiCalls: number;
+
+  @Column({ name: 'api_errors', type: 'integer', default: 0 })
+  apiErrors: number;
+
+  // Transacciones
+  @Column({ name: 'sales_count', type: 'integer', default: 0 })
+  salesCount: number;
+
+  @Column({ name: 'sales_amount', type: 'decimal', precision: 14, scale: 2, default: 0 })
+  salesAmount: number;
+
+  @Column({ name: 'invoices_generated', type: 'integer', default: 0 })
+  invoicesGenerated: number;
+
+  // Mobile
+  @Column({ name: 'mobile_sessions', type: 'integer', default: 0 })
+  mobileSessions: number;
+
+  @Column({ name: 'offline_syncs', type: 'integer', default: 0 })
+  offlineSyncs: number;
+
+  @Column({ name: 'payment_transactions', type: 'integer', default: 0 })
+  paymentTransactions: number;
+
+  // Calculado
+  @Column({ name: 'total_billable_amount', type: 'decimal', precision: 12, scale: 2, default: 0 })
+  totalBillableAmount: number;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+}
--- a/src/modules/core/entities/country.entity.ts
+++ b/src/modules/core/entities/country.entity.ts
@ -0,0 +1,35 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  Index,
+} from 'typeorm';
+
+@Entity({ schema: 'core', name: 'countries' })
+@Index('idx_countries_code', ['code'], { unique: true })
+export class Country {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'varchar', length: 2, nullable: false, unique: true })
+  code: string;
+
+  @Column({ type: 'varchar', length: 255, nullable: false })
+  name: string;
+
+  @Column({ type: 'varchar', length: 10, nullable: true, name: 'phone_code' })
+  phoneCode: string | null;
+
+  @Column({
+    type: 'varchar',
+    length: 3,
+    nullable: true,
+    name: 'currency_code',
+  })
+  currencyCode: string | null;
+
+  // Audit fields
+  @CreateDateColumn({ name: 'created_at', type: 'timestamp' })
+  createdAt: Date;
+}
--- a/src/modules/core/entities/currency-rate.entity.ts
+++ b/src/modules/core/entities/currency-rate.entity.ts
@ -0,0 +1,55 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { Currency } from './currency.entity';
+
+export type RateSource = 'manual' | 'banxico' | 'xe' | 'openexchange';
+
+@Entity({ schema: 'core', name: 'currency_rates' })
+@Index('idx_currency_rates_tenant', ['tenantId'])
+@Index('idx_currency_rates_from', ['fromCurrencyId'])
+@Index('idx_currency_rates_to', ['toCurrencyId'])
+@Index('idx_currency_rates_date', ['rateDate'])
+@Index('idx_currency_rates_lookup', ['fromCurrencyId', 'toCurrencyId', 'rateDate'])
+export class CurrencyRate {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'uuid', name: 'tenant_id', nullable: true })
+  tenantId: string | null;
+
+  @Column({ type: 'uuid', name: 'from_currency_id', nullable: false })
+  fromCurrencyId: string;
+
+  @ManyToOne(() => Currency)
+  @JoinColumn({ name: 'from_currency_id' })
+  fromCurrency: Currency;
+
+  @Column({ type: 'uuid', name: 'to_currency_id', nullable: false })
+  toCurrencyId: string;
+
+  @ManyToOne(() => Currency)
+  @JoinColumn({ name: 'to_currency_id' })
+  toCurrency: Currency;
+
+  @Column({ type: 'decimal', precision: 18, scale: 8, nullable: false })
+  rate: number;
+
+  @Column({ type: 'date', name: 'rate_date', nullable: false })
+  rateDate: Date;
+
+  @Column({ type: 'varchar', length: 50, default: 'manual' })
+  source: RateSource;
+
+  @Column({ type: 'uuid', name: 'created_by', nullable: true })
+  createdBy: string | null;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+}
--- a/src/modules/core/entities/currency.entity.ts
+++ b/src/modules/core/entities/currency.entity.ts
@ -0,0 +1,43 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  Index,
+} from 'typeorm';
+
+@Entity({ schema: 'core', name: 'currencies' })
+@Index('idx_currencies_code', ['code'], { unique: true })
+@Index('idx_currencies_active', ['active'])
+export class Currency {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'varchar', length: 3, nullable: false, unique: true })
+  code: string;
+
+  @Column({ type: 'varchar', length: 100, nullable: false })
+  name: string;
+
+  @Column({ type: 'varchar', length: 10, nullable: false })
+  symbol: string;
+
+  @Column({ type: 'integer', nullable: false, default: 2, name: 'decimals' })
+  decimals: number;
+
+  @Column({
+    type: 'decimal',
+    precision: 12,
+    scale: 6,
+    nullable: true,
+    default: 0.01,
+  })
+  rounding: number;
+
+  @Column({ type: 'boolean', nullable: false, default: true })
+  active: boolean;
+
+  // Audit fields
+  @CreateDateColumn({ name: 'created_at', type: 'timestamp' })
+  createdAt: Date;
+}
--- a/src/modules/core/entities/discount-rule.entity.ts
+++ b/src/modules/core/entities/discount-rule.entity.ts
@ -0,0 +1,163 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  DeleteDateColumn,
+  Index,
+} from 'typeorm';
+
+/**
+ * Tipo de descuento
+ */
+export enum DiscountType {
+  PERCENTAGE = 'percentage',  // Porcentaje del total
+  FIXED = 'fixed',            // Monto fijo
+  PRICE_OVERRIDE = 'price_override', // Precio especial
+}
+
+/**
+ * Aplicacion del descuento
+ */
+export enum DiscountAppliesTo {
+  ALL = 'all',              // Todos los productos
+  CATEGORY = 'category',     // Categoria especifica
+  PRODUCT = 'product',       // Producto especifico
+  CUSTOMER = 'customer',     // Cliente especifico
+  CUSTOMER_GROUP = 'customer_group', // Grupo de clientes
+}
+
+/**
+ * Condicion de activacion
+ */
+export enum DiscountCondition {
+  NONE = 'none',                    // Sin condicion
+  MIN_QUANTITY = 'min_quantity',    // Cantidad minima
+  MIN_AMOUNT = 'min_amount',        // Monto minimo
+  DATE_RANGE = 'date_range',        // Rango de fechas
+  FIRST_PURCHASE = 'first_purchase', // Primera compra
+}
+
+/**
+ * Regla de descuento
+ */
+@Entity({ schema: 'core', name: 'discount_rules' })
+@Index('idx_discount_rules_tenant_id', ['tenantId'])
+@Index('idx_discount_rules_code_tenant', ['tenantId', 'code'], { unique: true })
+@Index('idx_discount_rules_active', ['tenantId', 'isActive'])
+@Index('idx_discount_rules_dates', ['tenantId', 'startDate', 'endDate'])
+@Index('idx_discount_rules_priority', ['tenantId', 'priority'])
+export class DiscountRule {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'uuid', nullable: false, name: 'tenant_id' })
+  tenantId: string;
+
+  @Column({ type: 'uuid', nullable: true, name: 'company_id' })
+  companyId: string | null;
+
+  @Column({ type: 'varchar', length: 50, nullable: false })
+  code: string;
+
+  @Column({ type: 'varchar', length: 255, nullable: false })
+  name: string;
+
+  @Column({ type: 'text', nullable: true })
+  description: string | null;
+
+  @Column({
+    type: 'enum',
+    enum: DiscountType,
+    default: DiscountType.PERCENTAGE,
+    name: 'discount_type',
+  })
+  discountType: DiscountType;
+
+  @Column({
+    type: 'decimal',
+    precision: 15,
+    scale: 4,
+    nullable: false,
+    name: 'discount_value',
+  })
+  discountValue: number;
+
+  @Column({
+    type: 'decimal',
+    precision: 15,
+    scale: 2,
+    nullable: true,
+    name: 'max_discount_amount',
+  })
+  maxDiscountAmount: number | null;
+
+  @Column({
+    type: 'enum',
+    enum: DiscountAppliesTo,
+    default: DiscountAppliesTo.ALL,
+    name: 'applies_to',
+  })
+  appliesTo: DiscountAppliesTo;
+
+  @Column({ type: 'uuid', nullable: true, name: 'applies_to_id' })
+  appliesToId: string | null;
+
+  @Column({
+    type: 'enum',
+    enum: DiscountCondition,
+    default: DiscountCondition.NONE,
+    name: 'condition_type',
+  })
+  conditionType: DiscountCondition;
+
+  @Column({
+    type: 'decimal',
+    precision: 15,
+    scale: 4,
+    nullable: true,
+    name: 'condition_value',
+  })
+  conditionValue: number | null;
+
+  @Column({ type: 'timestamp', nullable: true, name: 'start_date' })
+  startDate: Date | null;
+
+  @Column({ type: 'timestamp', nullable: true, name: 'end_date' })
+  endDate: Date | null;
+
+  @Column({ type: 'integer', nullable: false, default: 10 })
+  priority: number;
+
+  @Column({ type: 'boolean', nullable: false, default: true, name: 'combinable' })
+  combinable: boolean;
+
+  @Column({ type: 'integer', nullable: true, name: 'usage_limit' })
+  usageLimit: number | null;
+
+  @Column({ type: 'integer', nullable: false, default: 0, name: 'usage_count' })
+  usageCount: number;
+
+  @Column({ type: 'boolean', nullable: false, default: true, name: 'is_active' })
+  isActive: boolean;
+
+  // Audit fields
+  @CreateDateColumn({ name: 'created_at', type: 'timestamp' })
+  createdAt: Date;
+
+  @Column({ type: 'uuid', nullable: true, name: 'created_by' })
+  createdBy: string | null;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamp', nullable: true })
+  updatedAt: Date | null;
+
+  @Column({ type: 'uuid', nullable: true, name: 'updated_by' })
+  updatedBy: string | null;
+
+  @DeleteDateColumn({ name: 'deleted_at', type: 'timestamptz', nullable: true })
+  deletedAt: Date | null;
+
+  @Column({ type: 'uuid', nullable: true, name: 'deleted_by' })
+  deletedBy: string | null;
+}
--- a/src/modules/core/entities/index.ts
+++ b/src/modules/core/entities/index.ts
@ -0,0 +1,19 @@
+/**
+ * Core Entities Index
+ */
+
+// Existing entities
+export { Tenant } from './tenant.entity';
+export { User } from './user.entity';
+
+// Catalog entities (propagated from erp-core)
+export { Country } from './country.entity';
+export { Currency } from './currency.entity';
+export { CurrencyRate, RateSource } from './currency-rate.entity';
+export { DiscountRule, DiscountType, DiscountAppliesTo, DiscountCondition } from './discount-rule.entity';
+export { PaymentTerm, PaymentTermLine, PaymentTermLineType } from './payment-term.entity';
+export { ProductCategory } from './product-category.entity';
+export { Sequence, ResetPeriod } from './sequence.entity';
+export { State } from './state.entity';
+export { Uom, UomType } from './uom.entity';
+export { UomCategory } from './uom-category.entity';
--- a/src/modules/core/entities/payment-term.entity.ts
+++ b/src/modules/core/entities/payment-term.entity.ts
@ -0,0 +1,144 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  DeleteDateColumn,
+  Index,
+  OneToMany,
+} from 'typeorm';
+
+/**
+ * Tipo de calculo para la linea del termino de pago
+ */
+export enum PaymentTermLineType {
+  BALANCE = 'balance',      // Saldo restante
+  PERCENT = 'percent',      // Porcentaje del total
+  FIXED = 'fixed',          // Monto fijo
+}
+
+/**
+ * Linea de termino de pago (para terminos con multiples vencimientos)
+ */
+@Entity({ schema: 'core', name: 'payment_term_lines' })
+@Index('idx_payment_term_lines_term', ['paymentTermId'])
+export class PaymentTermLine {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'uuid', nullable: false, name: 'payment_term_id' })
+  paymentTermId: string;
+
+  @Column({ type: 'integer', nullable: false, default: 1 })
+  sequence: number;
+
+  @Column({
+    type: 'enum',
+    enum: PaymentTermLineType,
+    default: PaymentTermLineType.BALANCE,
+    name: 'line_type',
+  })
+  lineType: PaymentTermLineType;
+
+  @Column({
+    type: 'decimal',
+    precision: 5,
+    scale: 2,
+    nullable: true,
+    name: 'value_percent',
+  })
+  valuePercent: number | null;
+
+  @Column({
+    type: 'decimal',
+    precision: 15,
+    scale: 2,
+    nullable: true,
+    name: 'value_amount',
+  })
+  valueAmount: number | null;
+
+  @Column({ type: 'integer', nullable: false, default: 0 })
+  days: number;
+
+  @Column({ type: 'integer', nullable: true, name: 'day_of_month' })
+  dayOfMonth: number | null;
+
+  @Column({ type: 'boolean', nullable: false, default: false, name: 'end_of_month' })
+  endOfMonth: boolean;
+}
+
+/**
+ * Termino de pago (Net 30, 50% advance + 50% on delivery, etc.)
+ */
+@Entity({ schema: 'core', name: 'payment_terms' })
+@Index('idx_payment_terms_tenant_id', ['tenantId'])
+@Index('idx_payment_terms_code_tenant', ['tenantId', 'code'], { unique: true })
+@Index('idx_payment_terms_active', ['tenantId', 'isActive'])
+export class PaymentTerm {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'uuid', nullable: false, name: 'tenant_id' })
+  tenantId: string;
+
+  @Column({ type: 'uuid', nullable: true, name: 'company_id' })
+  companyId: string | null;
+
+  @Column({ type: 'varchar', length: 50, nullable: false })
+  code: string;
+
+  @Column({ type: 'varchar', length: 255, nullable: false })
+  name: string;
+
+  @Column({ type: 'text', nullable: true })
+  description: string | null;
+
+  @Column({ type: 'integer', nullable: false, default: 0, name: 'due_days' })
+  dueDays: number;
+
+  @Column({
+    type: 'decimal',
+    precision: 5,
+    scale: 2,
+    nullable: true,
+    default: 0,
+    name: 'discount_percent',
+  })
+  discountPercent: number | null;
+
+  @Column({ type: 'integer', nullable: true, default: 0, name: 'discount_days' })
+  discountDays: number | null;
+
+  @Column({ type: 'boolean', nullable: false, default: false, name: 'is_immediate' })
+  isImmediate: boolean;
+
+  @Column({ type: 'boolean', nullable: false, default: true, name: 'is_active' })
+  isActive: boolean;
+
+  @Column({ type: 'integer', nullable: false, default: 0 })
+  sequence: number;
+
+  @OneToMany(() => PaymentTermLine, (line) => line.paymentTermId, { eager: true })
+  lines: PaymentTermLine[];
+
+  // Audit fields
+  @CreateDateColumn({ name: 'created_at', type: 'timestamp' })
+  createdAt: Date;
+
+  @Column({ type: 'uuid', nullable: true, name: 'created_by' })
+  createdBy: string | null;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamp', nullable: true })
+  updatedAt: Date | null;
+
+  @Column({ type: 'uuid', nullable: true, name: 'updated_by' })
+  updatedBy: string | null;
+
+  @DeleteDateColumn({ name: 'deleted_at', type: 'timestamptz', nullable: true })
+  deletedAt: Date | null;
+
+  @Column({ type: 'uuid', nullable: true, name: 'deleted_by' })
+  deletedBy: string | null;
+}
--- a/src/modules/core/entities/product-category.entity.ts
+++ b/src/modules/core/entities/product-category.entity.ts
@ -0,0 +1,79 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+  OneToMany,
+} from 'typeorm';
+
+@Entity({ schema: 'core', name: 'product_categories' })
+@Index('idx_product_categories_tenant_id', ['tenantId'])
+@Index('idx_product_categories_parent_id', ['parentId'])
+@Index('idx_product_categories_code_tenant', ['tenantId', 'code'], {
+  unique: true,
+})
+@Index('idx_product_categories_active', ['tenantId', 'active'], {
+  where: 'deleted_at IS NULL',
+})
+export class ProductCategory {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'uuid', nullable: false, name: 'tenant_id' })
+  tenantId: string;
+
+  @Column({ type: 'varchar', length: 255, nullable: false })
+  name: string;
+
+  @Column({ type: 'varchar', length: 50, nullable: true })
+  code: string | null;
+
+  @Column({ type: 'uuid', nullable: true, name: 'parent_id' })
+  parentId: string | null;
+
+  @Column({ type: 'text', nullable: true, name: 'full_path' })
+  fullPath: string | null;
+
+  @Column({ type: 'text', nullable: true })
+  notes: string | null;
+
+  @Column({ type: 'boolean', nullable: false, default: true })
+  active: boolean;
+
+  // Relations
+  @ManyToOne(() => ProductCategory, (category) => category.children, {
+    nullable: true,
+  })
+  @JoinColumn({ name: 'parent_id' })
+  parent: ProductCategory | null;
+
+  @OneToMany(() => ProductCategory, (category) => category.parent)
+  children: ProductCategory[];
+
+  // Audit fields
+  @CreateDateColumn({ name: 'created_at', type: 'timestamp' })
+  createdAt: Date;
+
+  @Column({ type: 'uuid', nullable: true, name: 'created_by' })
+  createdBy: string | null;
+
+  @UpdateDateColumn({
+    name: 'updated_at',
+    type: 'timestamp',
+    nullable: true,
+  })
+  updatedAt: Date | null;
+
+  @Column({ type: 'uuid', nullable: true, name: 'updated_by' })
+  updatedBy: string | null;
+
+  @Column({ type: 'timestamp', nullable: true, name: 'deleted_at' })
+  deletedAt: Date | null;
+
+  @Column({ type: 'uuid', nullable: true, name: 'deleted_by' })
+  deletedBy: string | null;
+}
--- a/src/modules/core/entities/sequence.entity.ts
+++ b/src/modules/core/entities/sequence.entity.ts
@ -0,0 +1,83 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+} from 'typeorm';
+
+export enum ResetPeriod {
+  NONE = 'none',
+  YEAR = 'year',
+  MONTH = 'month',
+}
+
+@Entity({ schema: 'core', name: 'sequences' })
+@Index('idx_sequences_tenant_id', ['tenantId'])
+@Index('idx_sequences_code_tenant', ['tenantId', 'code'], { unique: true })
+@Index('idx_sequences_active', ['tenantId', 'isActive'])
+export class Sequence {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'uuid', nullable: false, name: 'tenant_id' })
+  tenantId: string;
+
+  @Column({ type: 'uuid', nullable: true, name: 'company_id' })
+  companyId: string | null;
+
+  @Column({ type: 'varchar', length: 100, nullable: false })
+  code: string;
+
+  @Column({ type: 'varchar', length: 255, nullable: false })
+  name: string;
+
+  @Column({ type: 'varchar', length: 50, nullable: true })
+  prefix: string | null;
+
+  @Column({ type: 'varchar', length: 50, nullable: true })
+  suffix: string | null;
+
+  @Column({ type: 'integer', nullable: false, default: 1, name: 'next_number' })
+  nextNumber: number;
+
+  @Column({ type: 'integer', nullable: false, default: 4 })
+  padding: number;
+
+  @Column({
+    type: 'enum',
+    enum: ResetPeriod,
+    nullable: true,
+    default: ResetPeriod.NONE,
+    name: 'reset_period',
+  })
+  resetPeriod: ResetPeriod | null;
+
+  @Column({
+    type: 'timestamp',
+    nullable: true,
+    name: 'last_reset_date',
+  })
+  lastResetDate: Date | null;
+
+  @Column({ type: 'boolean', nullable: false, default: true, name: 'is_active' })
+  isActive: boolean;
+
+  // Audit fields
+  @CreateDateColumn({ name: 'created_at', type: 'timestamp' })
+  createdAt: Date;
+
+  @Column({ type: 'uuid', nullable: true, name: 'created_by' })
+  createdBy: string | null;
+
+  @UpdateDateColumn({
+    name: 'updated_at',
+    type: 'timestamp',
+    nullable: true,
+  })
+  updatedAt: Date | null;
+
+  @Column({ type: 'uuid', nullable: true, name: 'updated_by' })
+  updatedBy: string | null;
+}
--- a/src/modules/core/entities/state.entity.ts
+++ b/src/modules/core/entities/state.entity.ts
@ -0,0 +1,45 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { Country } from './country.entity';
+
+@Entity({ schema: 'core', name: 'states' })
+@Index('idx_states_country', ['countryId'])
+@Index('idx_states_code', ['code'])
+@Index('idx_states_country_code', ['countryId', 'code'], { unique: true })
+export class State {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'uuid', name: 'country_id', nullable: false })
+  countryId: string;
+
+  @ManyToOne(() => Country, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'country_id' })
+  country: Country;
+
+  @Column({ type: 'varchar', length: 10, nullable: false })
+  code: string;
+
+  @Column({ type: 'varchar', length: 255, nullable: false })
+  name: string;
+
+  @Column({ type: 'varchar', length: 50, nullable: true })
+  timezone: string | null;
+
+  @Column({ type: 'boolean', name: 'is_active', default: true })
+  isActive: boolean;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+}
--- a/src/modules/core/entities/tenant.entity.ts
+++ b/src/modules/core/entities/tenant.entity.ts
@ -0,0 +1,50 @@
+/**
+ * Tenant Entity
+ * Entidad para multi-tenancy
+ *
+ * @module Core
+ * @table core.tenants
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  OneToMany,
+  Index,
+} from 'typeorm';
+import { User } from './user.entity';
+
+@Entity({ schema: 'auth', name: 'tenants' })
+export class Tenant {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'varchar', length: 50, unique: true })
+  @Index()
+  code: string;
+
+  @Column({ type: 'varchar', length: 200 })
+  name: string;
+
+  @Column({ name: 'is_active', type: 'boolean', default: true })
+  isActive: boolean;
+
+  @Column({ type: 'jsonb', default: {} })
+  settings: Record<string, unknown>;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+
+  @Column({ name: 'deleted_at', type: 'timestamptz', nullable: true })
+  deletedAt: Date;
+
+  // Relations
+  @OneToMany(() => User, (user) => user.tenant)
+  users: User[];
+}
--- a/src/modules/core/entities/uom-category.entity.ts
+++ b/src/modules/core/entities/uom-category.entity.ts
@ -0,0 +1,45 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  OneToMany,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { Uom } from './uom.entity';
+import { Tenant } from './tenant.entity';
+
+@Entity({ schema: 'core', name: 'uom_categories' })
+@Index('idx_uom_categories_tenant', ['tenantId'])
+@Index('idx_uom_categories_tenant_name', ['tenantId', 'name'], { unique: true })
+export class UomCategory {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'uuid', nullable: false, name: 'tenant_id' })
+  tenantId: string;
+
+  @Column({ type: 'varchar', length: 100, nullable: false })
+  name: string;
+
+  @Column({ type: 'text', nullable: true })
+  description: string | null;
+
+  // Relations
+  @ManyToOne(() => Tenant)
+  @JoinColumn({ name: 'tenant_id' })
+  tenant: Tenant;
+
+  @OneToMany(() => Uom, (uom) => uom.category)
+  uoms: Uom[];
+
+  // Audit fields
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+}
--- a/src/modules/core/entities/uom.entity.ts
+++ b/src/modules/core/entities/uom.entity.ts
@ -0,0 +1,89 @@
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { UomCategory } from './uom-category.entity';
+import { Tenant } from './tenant.entity';
+
+export enum UomType {
+  REFERENCE = 'reference',
+  BIGGER = 'bigger',
+  SMALLER = 'smaller',
+}
+
+@Entity({ schema: 'core', name: 'uom' })
+@Index('idx_uom_tenant', ['tenantId'])
+@Index('idx_uom_category_id', ['categoryId'])
+@Index('idx_uom_code', ['code'])
+@Index('idx_uom_active', ['active'])
+@Index('idx_uom_tenant_category_name', ['tenantId', 'categoryId', 'name'], { unique: true })
+export class Uom {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'uuid', nullable: false, name: 'tenant_id' })
+  tenantId: string;
+
+  @Column({ type: 'uuid', nullable: false, name: 'category_id' })
+  categoryId: string;
+
+  @Column({ type: 'varchar', length: 100, nullable: false })
+  name: string;
+
+  @Column({ type: 'varchar', length: 20, nullable: true })
+  code: string | null;
+
+  @Column({
+    type: 'enum',
+    enum: UomType,
+    nullable: false,
+    default: UomType.REFERENCE,
+    name: 'uom_type',
+  })
+  uomType: UomType;
+
+  @Column({
+    type: 'decimal',
+    precision: 12,
+    scale: 6,
+    nullable: false,
+    default: 1.0,
+  })
+  factor: number;
+
+  @Column({
+    type: 'decimal',
+    precision: 12,
+    scale: 6,
+    nullable: true,
+    default: 0.01,
+  })
+  rounding: number;
+
+  @Column({ type: 'boolean', nullable: false, default: true })
+  active: boolean;
+
+  // Relations
+  @ManyToOne(() => Tenant)
+  @JoinColumn({ name: 'tenant_id' })
+  tenant: Tenant;
+
+  @ManyToOne(() => UomCategory, (category) => category.uoms, {
+    nullable: false,
+  })
+  @JoinColumn({ name: 'category_id' })
+  category: UomCategory;
+
+  // Audit fields
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+}
--- a/src/modules/core/entities/user.entity.ts
+++ b/src/modules/core/entities/user.entity.ts
@ -0,0 +1,78 @@
+/**
+ * User Entity
+ * Entidad de usuarios del sistema
+ *
+ * @module Core
+ * @table core.users
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  ManyToOne,
+  JoinColumn,
+  Index,
+} from 'typeorm';
+import { Tenant } from './tenant.entity';
+
+@Entity({ schema: 'auth', name: 'users' })
+@Index(['tenantId', 'email'], { unique: true })
+export class User {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ name: 'tenant_id', type: 'uuid', nullable: true })
+  tenantId: string;
+
+  @Column({ type: 'varchar', length: 255 })
+  email: string;
+
+  @Column({ type: 'varchar', length: 100, nullable: true })
+  username: string;
+
+  @Column({ name: 'password_hash', type: 'varchar', length: 255, select: false })
+  passwordHash: string;
+
+  @Column({ name: 'first_name', type: 'varchar', length: 100, nullable: true })
+  firstName: string;
+
+  @Column({ name: 'last_name', type: 'varchar', length: 100, nullable: true })
+  lastName: string;
+
+  @Column({ type: 'varchar', array: true, default: ['viewer'] })
+  roles: string[];
+
+  @Column({ name: 'is_active', type: 'boolean', default: true })
+  isActive: boolean;
+
+  @Column({ name: 'last_login_at', type: 'timestamptz', nullable: true })
+  lastLoginAt: Date;
+
+  @Column({ name: 'default_tenant_id', type: 'uuid', nullable: true })
+  defaultTenantId: string;
+
+  @Column({ name: 'deleted_at', type: 'timestamptz', nullable: true })
+  deletedAt: Date;
+
+  // Placeholder para relación de roles (se implementará en ST-004)
+  userRoles?: { role: { code: string } }[];
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+
+  // Relations
+  @ManyToOne(() => Tenant, (tenant) => tenant.users)
+  @JoinColumn({ name: 'tenant_id' })
+  tenant: Tenant;
+
+  // Computed property
+  get fullName(): string {
+    return [this.firstName, this.lastName].filter(Boolean).join(' ') || this.email;
+  }
+}
--- a/src/modules/invoices/entities/index.ts
+++ b/src/modules/invoices/entities/index.ts
@ -0,0 +1,8 @@
+/**
+ * Invoices Entities - Export
+ */
+
+export { Invoice, InvoiceType, InvoiceStatus, InvoiceContext } from './invoice.entity';
+export { InvoiceItem } from './invoice-item.entity';
+export { Payment } from './payment.entity';
+export { PaymentAllocation } from './payment-allocation.entity';
--- a/src/modules/invoices/entities/invoice-item.entity.ts
+++ b/src/modules/invoices/entities/invoice-item.entity.ts
@ -0,0 +1,95 @@
+/**
+ * InvoiceItem Entity
+ * Line items for unified invoices
+ * Compatible with erp-core invoice-item.entity
+ *
+ * @module Invoices
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { Invoice } from './invoice.entity';
+
+@Entity({ name: 'invoice_items', schema: 'billing' })
+export class InvoiceItem {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'invoice_id', type: 'uuid' })
+  invoiceId: string;
+
+  @ManyToOne(() => Invoice, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'invoice_id' })
+  invoice: Invoice;
+
+  @Index()
+  @Column({ name: 'product_id', type: 'uuid', nullable: true })
+  productId?: string;
+
+  @Column({ name: 'line_number', type: 'int', default: 1 })
+  lineNumber: number;
+
+  @Column({ name: 'product_sku', type: 'varchar', length: 50, nullable: true })
+  productSku?: string;
+
+  @Column({ name: 'product_name', type: 'varchar', length: 200 })
+  productName: string;
+
+  @Column({ type: 'text', nullable: true })
+  description?: string;
+
+  // SAT (Mexico)
+  @Column({ name: 'sat_product_code', type: 'varchar', length: 20, nullable: true })
+  satProductCode?: string;
+
+  @Column({ name: 'sat_unit_code', type: 'varchar', length: 10, nullable: true })
+  satUnitCode?: string;
+
+  @Column({ type: 'decimal', precision: 15, scale: 4, default: 1 })
+  quantity: number;
+
+  @Column({ type: 'varchar', length: 20, default: 'PZA' })
+  uom: string;
+
+  @Column({ name: 'unit_price', type: 'decimal', precision: 15, scale: 4, default: 0 })
+  unitPrice: number;
+
+  @Column({ name: 'discount_percent', type: 'decimal', precision: 5, scale: 2, default: 0 })
+  discountPercent: number;
+
+  @Column({ name: 'discount_amount', type: 'decimal', precision: 15, scale: 2, default: 0 })
+  discountAmount: number;
+
+  @Column({ name: 'tax_rate', type: 'decimal', precision: 5, scale: 2, default: 16.00 })
+  taxRate: number;
+
+  @Column({ name: 'tax_amount', type: 'decimal', precision: 15, scale: 2, default: 0 })
+  taxAmount: number;
+
+  @Column({ name: 'withholding_rate', type: 'decimal', precision: 5, scale: 2, default: 0 })
+  withholdingRate: number;
+
+  @Column({ name: 'withholding_amount', type: 'decimal', precision: 15, scale: 2, default: 0 })
+  withholdingAmount: number;
+
+  @Column({ type: 'decimal', precision: 15, scale: 2, default: 0 })
+  subtotal: number;
+
+  @Column({ type: 'decimal', precision: 15, scale: 2, default: 0 })
+  total: number;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+}
--- a/src/modules/invoices/entities/invoice.entity.ts
+++ b/src/modules/invoices/entities/invoice.entity.ts
@ -0,0 +1,187 @@
+/**
+ * Unified Invoice Entity
+ * Combines commercial and SaaS billing invoices
+ * Compatible with erp-core invoice.entity
+ *
+ * @module Invoices
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  DeleteDateColumn,
+  Index,
+  OneToMany,
+} from 'typeorm';
+import { InvoiceItem } from './invoice-item.entity';
+
+export type InvoiceType = 'sale' | 'purchase' | 'credit_note' | 'debit_note';
+export type InvoiceStatus = 'draft' | 'validated' | 'sent' | 'partial' | 'paid' | 'overdue' | 'void' | 'refunded' | 'cancelled' | 'voided';
+export type InvoiceContext = 'commercial' | 'saas';
+
+@Entity({ name: 'invoices', schema: 'billing' })
+export class Invoice {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Index({ unique: true })
+  @Column({ name: 'invoice_number', type: 'varchar', length: 30 })
+  invoiceNumber: string;
+
+  @Index()
+  @Column({ name: 'invoice_type', type: 'varchar', length: 20, default: 'sale' })
+  invoiceType: InvoiceType;
+
+  @Index()
+  @Column({ name: 'invoice_context', type: 'varchar', length: 20, default: 'commercial' })
+  invoiceContext: InvoiceContext;
+
+  // Commercial fields
+  @Column({ name: 'sales_order_id', type: 'uuid', nullable: true })
+  salesOrderId: string | null;
+
+  @Column({ name: 'purchase_order_id', type: 'uuid', nullable: true })
+  purchaseOrderId: string | null;
+
+  @Index()
+  @Column({ name: 'partner_id', type: 'uuid', nullable: true })
+  partnerId: string | null;
+
+  @Column({ name: 'partner_name', type: 'varchar', length: 200, nullable: true })
+  partnerName: string | null;
+
+  @Column({ name: 'partner_tax_id', type: 'varchar', length: 50, nullable: true })
+  partnerTaxId: string | null;
+
+  // SaaS billing fields
+  @Index()
+  @Column({ name: 'subscription_id', type: 'uuid', nullable: true })
+  subscriptionId: string | null;
+
+  @Column({ name: 'period_start', type: 'date', nullable: true })
+  periodStart: Date | null;
+
+  @Column({ name: 'period_end', type: 'date', nullable: true })
+  periodEnd: Date | null;
+
+  // Billing information
+  @Column({ name: 'billing_name', type: 'varchar', length: 200, nullable: true })
+  billingName: string | null;
+
+  @Column({ name: 'billing_email', type: 'varchar', length: 255, nullable: true })
+  billingEmail: string | null;
+
+  @Column({ name: 'billing_address', type: 'jsonb', nullable: true })
+  billingAddress: Record<string, any> | null;
+
+  @Column({ name: 'tax_id', type: 'varchar', length: 50, nullable: true })
+  taxId: string | null;
+
+  // Dates
+  @Index()
+  @Column({ name: 'invoice_date', type: 'date', default: () => 'CURRENT_DATE' })
+  invoiceDate: Date;
+
+  @Column({ name: 'due_date', type: 'date', nullable: true })
+  dueDate: Date | null;
+
+  @Column({ name: 'payment_date', type: 'date', nullable: true })
+  paymentDate: Date | null;
+
+  @Column({ name: 'paid_at', type: 'timestamptz', nullable: true })
+  paidAt: Date | null;
+
+  // Amounts
+  @Column({ type: 'varchar', length: 3, default: 'MXN' })
+  currency: string;
+
+  @Column({ name: 'exchange_rate', type: 'decimal', precision: 10, scale: 6, default: 1 })
+  exchangeRate: number;
+
+  @Column({ type: 'decimal', precision: 15, scale: 2, default: 0 })
+  subtotal: number;
+
+  @Column({ name: 'tax_amount', type: 'decimal', precision: 15, scale: 2, default: 0 })
+  taxAmount: number;
+
+  @Column({ name: 'withholding_tax', type: 'decimal', precision: 15, scale: 2, default: 0 })
+  withholdingTax: number;
+
+  @Column({ name: 'discount_amount', type: 'decimal', precision: 15, scale: 2, default: 0 })
+  discountAmount: number;
+
+  @Column({ type: 'decimal', precision: 15, scale: 2, default: 0 })
+  total: number;
+
+  @Column({ name: 'amount_paid', type: 'decimal', precision: 15, scale: 2, default: 0 })
+  amountPaid: number;
+
+  @Column({ name: 'amount_due', type: 'decimal', precision: 15, scale: 2, insert: false, update: false, nullable: true })
+  amountDue: number | null;
+
+  @Column({ name: 'paid_amount', type: 'decimal', precision: 15, scale: 2, default: 0 })
+  paidAmount: number;
+
+  // Payment details
+  @Column({ name: 'payment_term_days', type: 'int', default: 0 })
+  paymentTermDays: number;
+
+  @Column({ name: 'payment_method', type: 'varchar', length: 50, nullable: true })
+  paymentMethod: string | null;
+
+  @Column({ name: 'payment_reference', type: 'varchar', length: 100, nullable: true })
+  paymentReference: string | null;
+
+  // Status
+  @Index()
+  @Column({ type: 'varchar', length: 20, default: 'draft' })
+  status: InvoiceStatus;
+
+  // CFDI (Mexico)
+  @Index()
+  @Column({ name: 'cfdi_uuid', type: 'varchar', length: 40, nullable: true })
+  cfdiUuid: string | null;
+
+  @Column({ name: 'cfdi_status', type: 'varchar', length: 20, nullable: true })
+  cfdiStatus: string | null;
+
+  @Column({ name: 'cfdi_xml', type: 'text', nullable: true })
+  cfdiXml: string | null;
+
+  @Column({ name: 'cfdi_pdf_url', type: 'varchar', length: 500, nullable: true })
+  cfdiPdfUrl: string | null;
+
+  // Notes
+  @Column({ type: 'text', nullable: true })
+  notes: string | null;
+
+  @Column({ name: 'internal_notes', type: 'text', nullable: true })
+  internalNotes: string | null;
+
+  // Audit
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @Column({ name: 'created_by', type: 'uuid', nullable: true })
+  createdBy: string | null;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+
+  @Column({ name: 'updated_by', type: 'uuid', nullable: true })
+  updatedBy: string | null;
+
+  @DeleteDateColumn({ name: 'deleted_at', type: 'timestamptz', nullable: true })
+  deletedAt: Date | null;
+
+  // Relations
+  @OneToMany(() => InvoiceItem, (item) => item.invoice, { cascade: true })
+  items: InvoiceItem[];
+}
--- a/src/modules/invoices/entities/payment-allocation.entity.ts
+++ b/src/modules/invoices/entities/payment-allocation.entity.ts
@ -0,0 +1,53 @@
+/**
+ * PaymentAllocation Entity
+ * Links payments to invoices
+ * Compatible with erp-core payment-allocation.entity
+ *
+ * @module Invoices
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { Payment } from './payment.entity';
+import { Invoice } from './invoice.entity';
+
+@Entity({ name: 'payment_allocations', schema: 'billing' })
+export class PaymentAllocation {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'payment_id', type: 'uuid' })
+  paymentId: string;
+
+  @ManyToOne(() => Payment, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'payment_id' })
+  payment: Payment;
+
+  @Index()
+  @Column({ name: 'invoice_id', type: 'uuid' })
+  invoiceId: string;
+
+  @ManyToOne(() => Invoice, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'invoice_id' })
+  invoice: Invoice;
+
+  @Column({ type: 'decimal', precision: 15, scale: 2 })
+  amount: number;
+
+  @Column({ name: 'allocation_date', type: 'date', default: () => 'CURRENT_DATE' })
+  allocationDate: Date;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @Column({ name: 'created_by', type: 'uuid', nullable: true })
+  createdBy?: string;
+}
--- a/src/modules/invoices/entities/payment.entity.ts
+++ b/src/modules/invoices/entities/payment.entity.ts
@ -0,0 +1,89 @@
+/**
+ * Payment Entity
+ * Payment received or made
+ * Compatible with erp-core payment.entity
+ *
+ * @module Invoices
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  DeleteDateColumn,
+  Index,
+} from 'typeorm';
+
+@Entity({ name: 'payments', schema: 'billing' })
+export class Payment {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Index()
+  @Column({ name: 'payment_number', type: 'varchar', length: 30 })
+  paymentNumber: string;
+
+  @Index()
+  @Column({ name: 'payment_type', type: 'varchar', length: 20, default: 'received' })
+  paymentType: 'received' | 'made';
+
+  @Index()
+  @Column({ name: 'partner_id', type: 'uuid' })
+  partnerId: string;
+
+  @Column({ name: 'partner_name', type: 'varchar', length: 200, nullable: true })
+  partnerName: string;
+
+  @Column({ type: 'varchar', length: 3, default: 'MXN' })
+  currency: string;
+
+  @Column({ type: 'decimal', precision: 15, scale: 2 })
+  amount: number;
+
+  @Column({ name: 'exchange_rate', type: 'decimal', precision: 10, scale: 6, default: 1 })
+  exchangeRate: number;
+
+  @Column({ name: 'payment_date', type: 'date', default: () => 'CURRENT_DATE' })
+  paymentDate: Date;
+
+  @Index()
+  @Column({ name: 'payment_method', type: 'varchar', length: 50 })
+  paymentMethod: string;
+
+  @Column({ type: 'varchar', length: 100, nullable: true })
+  reference: string;
+
+  @Column({ name: 'bank_account_id', type: 'uuid', nullable: true })
+  bankAccountId: string;
+
+  @Index()
+  @Column({ type: 'varchar', length: 20, default: 'draft' })
+  status: 'draft' | 'confirmed' | 'reconciled' | 'cancelled';
+
+  @Column({ type: 'text', nullable: true })
+  notes: string;
+
+  @Column({ name: 'cfdi_uuid', type: 'varchar', length: 40, nullable: true })
+  cfdiUuid: string;
+
+  @Column({ name: 'cfdi_status', type: 'varchar', length: 20, nullable: true })
+  cfdiStatus: string;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @Column({ name: 'created_by', type: 'uuid', nullable: true })
+  createdBy?: string;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+
+  @DeleteDateColumn({ name: 'deleted_at', type: 'timestamptz', nullable: true })
+  deletedAt: Date;
+}
--- a/src/modules/notifications/entities/channel.entity.ts
+++ b/src/modules/notifications/entities/channel.entity.ts
@ -0,0 +1,65 @@
+/**
+ * Channel Entity
+ * Notification delivery channel configuration
+ * Compatible with erp-core channel.entity
+ *
+ * @module Notifications
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+} from 'typeorm';
+
+export type ChannelType = 'email' | 'sms' | 'push' | 'whatsapp' | 'in_app' | 'webhook';
+
+@Entity({ name: 'channels', schema: 'notifications' })
+export class Channel {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column({ type: 'varchar', length: 30, unique: true })
+  code: string;
+
+  @Column({ type: 'varchar', length: 100 })
+  name: string;
+
+  @Column({ type: 'text', nullable: true })
+  description: string;
+
+  @Column({ name: 'channel_type', type: 'varchar', length: 30 })
+  channelType: ChannelType;
+
+  @Column({ type: 'varchar', length: 50, nullable: true })
+  provider: string;
+
+  @Column({ name: 'provider_config', type: 'jsonb', default: {} })
+  providerConfig: Record<string, any>;
+
+  @Column({ name: 'rate_limit_per_minute', type: 'int', nullable: true })
+  rateLimitPerMinute: number;
+
+  @Column({ name: 'rate_limit_per_hour', type: 'int', nullable: true })
+  rateLimitPerHour: number;
+
+  @Column({ name: 'rate_limit_per_day', type: 'int', nullable: true })
+  rateLimitPerDay: number;
+
+  @Column({ name: 'is_active', type: 'boolean', default: true })
+  isActive: boolean;
+
+  @Column({ name: 'is_default', type: 'boolean', default: false })
+  isDefault: boolean;
+
+  @Column({ type: 'jsonb', default: {} })
+  metadata: Record<string, any>;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+}
--- a/src/modules/notifications/entities/in-app-notification.entity.ts
+++ b/src/modules/notifications/entities/in-app-notification.entity.ts
@ -0,0 +1,85 @@
+/**
+ * InAppNotification Entity
+ * In-app notification with read/archive tracking
+ * Compatible with erp-core in-app-notification.entity
+ *
+ * @module Notifications
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  Index,
+} from 'typeorm';
+
+export type InAppCategory = 'info' | 'success' | 'warning' | 'error' | 'task';
+export type InAppPriority = 'low' | 'normal' | 'high' | 'urgent';
+export type InAppActionType = 'link' | 'modal' | 'function';
+
+@Entity({ name: 'in_app_notifications', schema: 'notifications' })
+export class InAppNotification {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Index()
+  @Column({ name: 'user_id', type: 'uuid' })
+  userId: string;
+
+  @Column({ type: 'varchar', length: 200 })
+  title: string;
+
+  @Column({ type: 'text' })
+  message: string;
+
+  @Column({ type: 'varchar', length: 50, nullable: true })
+  icon: string;
+
+  @Column({ type: 'varchar', length: 20, nullable: true })
+  color: string;
+
+  @Column({ name: 'action_type', type: 'varchar', length: 20, nullable: true })
+  actionType: InAppActionType;
+
+  @Column({ name: 'action_url', type: 'text', nullable: true })
+  actionUrl: string;
+
+  @Column({ name: 'action_data', type: 'jsonb', nullable: true })
+  actionData: Record<string, any>;
+
+  @Column({ type: 'varchar', length: 30, default: 'info' })
+  category: InAppCategory;
+
+  @Column({ name: 'context_type', type: 'varchar', length: 100, nullable: true })
+  contextType: string;
+
+  @Column({ name: 'context_id', type: 'uuid', nullable: true })
+  contextId: string;
+
+  @Column({ name: 'is_read', type: 'boolean', default: false })
+  isRead: boolean;
+
+  @Column({ name: 'read_at', type: 'timestamptz', nullable: true })
+  readAt: Date;
+
+  @Column({ name: 'is_archived', type: 'boolean', default: false })
+  isArchived: boolean;
+
+  @Column({ name: 'archived_at', type: 'timestamptz', nullable: true })
+  archivedAt: Date;
+
+  @Column({ type: 'varchar', length: 20, default: 'normal' })
+  priority: InAppPriority;
+
+  @Column({ name: 'expires_at', type: 'timestamptz', nullable: true })
+  expiresAt: Date;
+
+  @Index()
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+}
--- a/src/modules/notifications/entities/index.ts
+++ b/src/modules/notifications/entities/index.ts
@ -0,0 +1,10 @@
+/**
+ * Notifications Entities - Export
+ */
+
+export { Channel, ChannelType } from './channel.entity';
+export { NotificationTemplate, TemplateTranslation, TemplateCategory } from './template.entity';
+export { NotificationPreference, DigestFrequency } from './preference.entity';
+export { Notification, NotificationStatus, NotificationPriority } from './notification.entity';
+export { NotificationBatch, BatchStatus, AudienceType } from './notification-batch.entity';
+export { InAppNotification, InAppCategory, InAppPriority, InAppActionType } from './in-app-notification.entity';
--- a/src/modules/notifications/entities/notification-batch.entity.ts
+++ b/src/modules/notifications/entities/notification-batch.entity.ts
@ -0,0 +1,96 @@
+/**
+ * NotificationBatch Entity
+ * Batch notification campaigns with audience targeting
+ * Compatible with erp-core notification-batch.entity
+ *
+ * @module Notifications
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { NotificationTemplate } from './template.entity';
+import { ChannelType } from './channel.entity';
+
+export type BatchStatus = 'draft' | 'scheduled' | 'processing' | 'completed' | 'failed' | 'cancelled';
+export type AudienceType = 'all_users' | 'segment' | 'custom';
+
+@Entity({ name: 'notification_batches', schema: 'notifications' })
+export class NotificationBatch {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Column({ type: 'varchar', length: 200 })
+  name: string;
+
+  @Column({ type: 'text', nullable: true })
+  description: string;
+
+  @Column({ name: 'template_id', type: 'uuid', nullable: true })
+  templateId: string;
+
+  @Column({ name: 'channel_type', type: 'varchar', length: 30 })
+  channelType: ChannelType;
+
+  @Column({ name: 'audience_type', type: 'varchar', length: 30 })
+  audienceType: AudienceType;
+
+  @Column({ name: 'audience_filter', type: 'jsonb', default: {} })
+  audienceFilter: Record<string, any>;
+
+  @Column({ type: 'jsonb', default: {} })
+  variables: Record<string, any>;
+
+  @Index()
+  @Column({ name: 'scheduled_at', type: 'timestamptz', nullable: true })
+  scheduledAt: Date;
+
+  @Index()
+  @Column({ type: 'varchar', length: 20, default: 'draft' })
+  status: BatchStatus;
+
+  @Column({ name: 'total_recipients', type: 'int', default: 0 })
+  totalRecipients: number;
+
+  @Column({ name: 'sent_count', type: 'int', default: 0 })
+  sentCount: number;
+
+  @Column({ name: 'delivered_count', type: 'int', default: 0 })
+  deliveredCount: number;
+
+  @Column({ name: 'failed_count', type: 'int', default: 0 })
+  failedCount: number;
+
+  @Column({ name: 'read_count', type: 'int', default: 0 })
+  readCount: number;
+
+  @Column({ name: 'started_at', type: 'timestamptz', nullable: true })
+  startedAt: Date;
+
+  @Column({ name: 'completed_at', type: 'timestamptz', nullable: true })
+  completedAt: Date;
+
+  @ManyToOne(() => NotificationTemplate, { onDelete: 'SET NULL', nullable: true })
+  @JoinColumn({ name: 'template_id' })
+  template: NotificationTemplate | null;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+
+  @Column({ name: 'created_by', type: 'uuid', nullable: true })
+  createdBy: string | null;
+}
--- a/src/modules/notifications/entities/notification.entity.ts
+++ b/src/modules/notifications/entities/notification.entity.ts
@ -0,0 +1,138 @@
+/**
+ * Notification Entity
+ * Individual notification with delivery tracking
+ * Compatible with erp-core notification.entity
+ *
+ * @module Notifications
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { NotificationTemplate } from './template.entity';
+import { Channel, ChannelType } from './channel.entity';
+
+export type NotificationStatus = 'pending' | 'queued' | 'sending' | 'sent' | 'delivered' | 'read' | 'failed' | 'cancelled';
+export type NotificationPriority = 'low' | 'normal' | 'high' | 'urgent';
+
+@Entity({ name: 'notifications', schema: 'notifications' })
+export class Notification {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Index()
+  @Column({ name: 'user_id', type: 'uuid', nullable: true })
+  userId: string;
+
+  @Column({ name: 'recipient_email', type: 'varchar', length: 255, nullable: true })
+  recipientEmail: string;
+
+  @Column({ name: 'recipient_phone', type: 'varchar', length: 20, nullable: true })
+  recipientPhone: string;
+
+  @Column({ name: 'recipient_device_id', type: 'varchar', length: 255, nullable: true })
+  recipientDeviceId: string;
+
+  @Index()
+  @Column({ name: 'template_id', type: 'uuid', nullable: true })
+  templateId: string;
+
+  @Column({ name: 'template_code', type: 'varchar', length: 100, nullable: true })
+  templateCode: string;
+
+  @Column({ name: 'channel_type', type: 'varchar', length: 30 })
+  channelType: ChannelType;
+
+  @Index()
+  @Column({ name: 'channel_id', type: 'uuid', nullable: true })
+  channelId: string;
+
+  @Column({ type: 'varchar', length: 500, nullable: true })
+  subject: string;
+
+  @Column({ type: 'text', nullable: true })
+  body: string;
+
+  @Column({ name: 'body_html', type: 'text', nullable: true })
+  bodyHtml: string;
+
+  @Column({ type: 'jsonb', default: {} })
+  variables: Record<string, any>;
+
+  @Column({ name: 'context_type', type: 'varchar', length: 100, nullable: true })
+  contextType: string;
+
+  @Column({ name: 'context_id', type: 'uuid', nullable: true })
+  contextId: string;
+
+  @Column({ type: 'varchar', length: 20, default: 'normal' })
+  priority: NotificationPriority;
+
+  @Index()
+  @Column({ type: 'varchar', length: 20, default: 'pending' })
+  status: NotificationStatus;
+
+  @Column({ name: 'queued_at', type: 'timestamptz', nullable: true })
+  queuedAt: Date;
+
+  @Column({ name: 'sent_at', type: 'timestamptz', nullable: true })
+  sentAt: Date;
+
+  @Column({ name: 'delivered_at', type: 'timestamptz', nullable: true })
+  deliveredAt: Date;
+
+  @Column({ name: 'read_at', type: 'timestamptz', nullable: true })
+  readAt: Date;
+
+  @Column({ name: 'failed_at', type: 'timestamptz', nullable: true })
+  failedAt: Date;
+
+  @Column({ name: 'error_message', type: 'text', nullable: true })
+  errorMessage: string;
+
+  @Column({ name: 'retry_count', type: 'int', default: 0 })
+  retryCount: number;
+
+  @Column({ name: 'max_retries', type: 'int', default: 3 })
+  maxRetries: number;
+
+  @Column({ name: 'next_retry_at', type: 'timestamptz', nullable: true })
+  nextRetryAt: Date;
+
+  @Column({ name: 'provider_message_id', type: 'varchar', length: 255, nullable: true })
+  providerMessageId: string;
+
+  @Column({ name: 'provider_response', type: 'jsonb', nullable: true })
+  providerResponse: Record<string, any>;
+
+  @Column({ type: 'jsonb', default: {} })
+  metadata: Record<string, any>;
+
+  @Column({ name: 'expires_at', type: 'timestamptz', nullable: true })
+  expiresAt: Date;
+
+  @ManyToOne(() => NotificationTemplate, { onDelete: 'SET NULL', nullable: true })
+  @JoinColumn({ name: 'template_id' })
+  template: NotificationTemplate | null;
+
+  @ManyToOne(() => Channel, { onDelete: 'SET NULL', nullable: true })
+  @JoinColumn({ name: 'channel_id' })
+  channel: Channel | null;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+}
--- a/src/modules/notifications/entities/preference.entity.ts
+++ b/src/modules/notifications/entities/preference.entity.ts
@ -0,0 +1,82 @@
+/**
+ * NotificationPreference Entity
+ * User notification preferences per tenant
+ * Compatible with erp-core preference.entity
+ *
+ * @module Notifications
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  Unique,
+} from 'typeorm';
+
+export type DigestFrequency = 'instant' | 'hourly' | 'daily' | 'weekly';
+
+@Entity({ name: 'notification_preferences', schema: 'notifications' })
+@Unique(['userId', 'tenantId'])
+export class NotificationPreference {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'user_id', type: 'uuid' })
+  userId: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid' })
+  tenantId: string;
+
+  @Column({ name: 'global_enabled', type: 'boolean', default: true })
+  globalEnabled: boolean;
+
+  @Column({ name: 'quiet_hours_start', type: 'time', nullable: true })
+  quietHoursStart: string;
+
+  @Column({ name: 'quiet_hours_end', type: 'time', nullable: true })
+  quietHoursEnd: string;
+
+  @Column({ type: 'varchar', length: 50, default: 'America/Mexico_City' })
+  timezone: string;
+
+  @Column({ name: 'email_enabled', type: 'boolean', default: true })
+  emailEnabled: boolean;
+
+  @Column({ name: 'sms_enabled', type: 'boolean', default: false })
+  smsEnabled: boolean;
+
+  @Column({ name: 'push_enabled', type: 'boolean', default: true })
+  pushEnabled: boolean;
+
+  @Column({ name: 'whatsapp_enabled', type: 'boolean', default: false })
+  whatsappEnabled: boolean;
+
+  @Column({ name: 'in_app_enabled', type: 'boolean', default: true })
+  inAppEnabled: boolean;
+
+  @Column({ name: 'category_preferences', type: 'jsonb', default: {} })
+  categoryPreferences: Record<string, any>;
+
+  @Column({ name: 'digest_frequency', type: 'varchar', length: 20, default: 'instant' })
+  digestFrequency: DigestFrequency;
+
+  @Column({ name: 'digest_day', type: 'int', nullable: true })
+  digestDay: number;
+
+  @Column({ name: 'digest_hour', type: 'int', nullable: true })
+  digestHour: number;
+
+  @Column({ type: 'jsonb', default: {} })
+  metadata: Record<string, any>;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+}
--- a/src/modules/notifications/entities/template.entity.ts
+++ b/src/modules/notifications/entities/template.entity.ts
@ -0,0 +1,126 @@
+/**
+ * NotificationTemplate + TemplateTranslation Entities
+ * Template system with i18n support
+ * Compatible with erp-core template.entity
+ *
+ * @module Notifications
+ */
+
+import {
+  Entity,
+  PrimaryGeneratedColumn,
+  Column,
+  CreateDateColumn,
+  UpdateDateColumn,
+  Index,
+  Unique,
+  OneToMany,
+  ManyToOne,
+  JoinColumn,
+} from 'typeorm';
+import { ChannelType } from './channel.entity';
+
+export type TemplateCategory = 'system' | 'marketing' | 'transactional' | 'alert';
+
+@Entity({ name: 'notification_templates', schema: 'notifications' })
+@Unique(['tenantId', 'code', 'channelType'])
+export class NotificationTemplate {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'tenant_id', type: 'uuid', nullable: true })
+  tenantId: string | null;
+
+  @Index()
+  @Column({ type: 'varchar', length: 100 })
+  code: string;
+
+  @Column({ type: 'varchar', length: 200 })
+  name: string;
+
+  @Column({ type: 'text', nullable: true })
+  description: string;
+
+  @Column({ type: 'varchar', length: 30, nullable: true })
+  category: TemplateCategory;
+
+  @Index()
+  @Column({ name: 'channel_type', type: 'varchar', length: 30 })
+  channelType: ChannelType;
+
+  @Column({ type: 'varchar', length: 500, nullable: true })
+  subject: string;
+
+  @Column({ name: 'body_template', type: 'text', nullable: true })
+  bodyTemplate: string;
+
+  @Column({ name: 'body_html', type: 'text', nullable: true })
+  bodyHtml: string;
+
+  @Column({ name: 'available_variables', type: 'jsonb', default: [] })
+  availableVariables: string[];
+
+  @Column({ name: 'default_locale', type: 'varchar', length: 10, default: 'es-MX' })
+  defaultLocale: string;
+
+  @Column({ name: 'is_active', type: 'boolean', default: true })
+  isActive: boolean;
+
+  @Column({ name: 'is_system', type: 'boolean', default: false })
+  isSystem: boolean;
+
+  @Column({ type: 'int', default: 1 })
+  version: number;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+
+  @Column({ name: 'created_by', type: 'uuid', nullable: true })
+  createdBy: string | null;
+
+  @Column({ name: 'updated_by', type: 'uuid', nullable: true })
+  updatedBy: string | null;
+
+  @OneToMany(() => TemplateTranslation, (t) => t.template)
+  translations: TemplateTranslation[];
+}
+
+@Entity({ name: 'template_translations', schema: 'notifications' })
+@Unique(['templateId', 'locale'])
+export class TemplateTranslation {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Index()
+  @Column({ name: 'template_id', type: 'uuid' })
+  templateId: string;
+
+  @Column({ type: 'varchar', length: 10 })
+  locale: string;
+
+  @Column({ type: 'varchar', length: 500, nullable: true })
+  subject: string;
+
+  @Column({ name: 'body_template', type: 'text', nullable: true })
+  bodyTemplate: string;
+
+  @Column({ name: 'body_html', type: 'text', nullable: true })
+  bodyHtml: string;
+
+  @Column({ name: 'is_active', type: 'boolean', default: true })
+  isActive: boolean;
+
+  @CreateDateColumn({ name: 'created_at', type: 'timestamptz' })
+  createdAt: Date;
+
+  @UpdateDateColumn({ name: 'updated_at', type: 'timestamptz' })
+  updatedAt: Date;
+
+  @ManyToOne(() => NotificationTemplate, (t) => t.translations, { onDelete: 'CASCADE' })
+  @JoinColumn({ name: 'template_id' })
+  template: NotificationTemplate;
+}