B2B-88: add starter kit structure and elements

packages/analytics/README.md

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+# Analytics - @kit/analytics
+
+@kit/analytics Package provides a simple and consistent API for tracking analytics events in web applications.
+
+Please refer to the [documentation](https://makerkit.dev/docs/next-supabase-turbo/analytics/analytics-and-events).

packages/analytics/eslint.config.mjs

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+import eslintConfigBase from '@kit/eslint-config/base.js';
+
+export default eslintConfigBase;

packages/analytics/node_modules/@kit/eslint-config

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+../../../../tooling/eslint

packages/analytics/node_modules/@kit/prettier-config

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+../../../../tooling/prettier

packages/analytics/node_modules/@kit/tsconfig

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+../../../../tooling/typescript

packages/analytics/node_modules/@types/node

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+../../../../node_modules/.pnpm/@types+node@22.15.30/node_modules/@types/node

packages/analytics/package.json

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+{
+  "name": "@kit/analytics",
+  "private": true,
+  "version": "0.1.0",
+  "scripts": {
+    "clean": "git clean -xdf .turbo node_modules",
+    "format": "prettier --check \"**/*.{ts,tsx}\"",
+    "lint": "eslint .",
+    "typecheck": "tsc --noEmit"
+  },
+  "prettier": "@kit/prettier-config",
+  "exports": {
+    ".": "./src/index.ts"
+  },
+  "devDependencies": {
+    "@kit/eslint-config": "workspace:*",
+    "@kit/prettier-config": "workspace:*",
+    "@kit/tsconfig": "workspace:*",
+    "@types/node": "^22.15.18"
+  },
+  "typesVersions": {
+    "*": {
+      "*": [
+        "src/*"
+      ]
+    }
+  }
+}

packages/analytics/src/analytics-manager.ts

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+import { NullAnalyticsService } from './null-analytics-service';
+import type {
+  AnalyticsManager,
+  AnalyticsService,
+  CreateAnalyticsManagerOptions,
+} from './types';
+
+export function createAnalyticsManager<T extends string, Config extends object>(
+  options: CreateAnalyticsManagerOptions<T, Config>,
+): AnalyticsManager {
+  const activeServices = new Map<T, AnalyticsService>();
+
+  const getActiveServices = (): AnalyticsService[] => {
+    if (activeServices.size === 0) {
+      console.debug(
+        'No active analytics services. Using NullAnalyticsService.',
+      );
+
+      return [NullAnalyticsService];
+    }
+
+    return Array.from(activeServices.values());
+  };
+
+  const registerActiveServices = (
+    options: CreateAnalyticsManagerOptions<T, Config>,
+  ) => {
+    Object.keys(options.providers).forEach((provider) => {
+      const providerKey = provider as keyof typeof options.providers;
+      const factory = options.providers[providerKey];
+
+      if (!factory) {
+        console.warn(
+          `Analytics provider '${provider}' not registered. Skipping initialization.`,
+        );
+
+        return;
+      }
+
+      const service = factory();
+      activeServices.set(provider as T, service);
+
+      void service.initialize();
+    });
+  };
+
+  registerActiveServices(options);
+
+  return {
+    addProvider: (provider: T, config: Config) => {
+      const factory = options.providers[provider];
+
+      if (!factory) {
+        console.warn(
+          `Analytics provider '${provider}' not registered. Skipping initialization.`,
+        );
+
+        return Promise.resolve();
+      }
+
+      const service = factory(config);
+      activeServices.set(provider, service);
+
+      return service.initialize();
+    },
+
+    removeProvider: (provider: T) => {
+      activeServices.delete(provider);
+    },
+
+    identify: (userId: string, traits?: Record<string, string>) => {
+      return Promise.all(
+        getActiveServices().map((service) => service.identify(userId, traits)),
+      );
+    },
+
+    trackPageView: (path: string) => {
+      return Promise.all(
+        getActiveServices().map((service) => service.trackPageView(path)),
+      );
+    },
+
+    trackEvent: (
+      eventName: string,
+      eventProperties?: Record<string, string | string[]>,
+    ) => {
+      return Promise.all(
+        getActiveServices().map((service) =>
+          service.trackEvent(eventName, eventProperties),
+        ),
+      );
+    },
+  };
+}

packages/analytics/src/index.ts

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+import { createAnalyticsManager } from './analytics-manager';
+import { NullAnalyticsService } from './null-analytics-service';
+import type { AnalyticsManager } from './types';
+
+export const analytics: AnalyticsManager = createAnalyticsManager({
+  providers: {
+    null: () => NullAnalyticsService,
+  },
+});

packages/analytics/src/null-analytics-service.ts

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+import { AnalyticsService } from './types';
+
+const noop = (event: string) => {
+  // do nothing - this is to prevent errors when the analytics service is not initialized
+
+  return async (...args: unknown[]) => {
+    console.debug(
+      `Noop analytics service called with event: ${event}`,
+      ...args.filter(Boolean),
+    );
+  };
+};
+
+/**
+ * Null analytics service that does nothing. It is initialized with a noop function. This is useful for testing or when
+ * the user is calling analytics methods before the analytics service is initialized.
+ */
+export const NullAnalyticsService: AnalyticsService = {
+  initialize: noop('initialize'),
+  trackPageView: noop('trackPageView'),
+  trackEvent: noop('trackEvent'),
+  identify: noop('identify'),
+};

packages/analytics/src/types.ts

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+interface TrackEvent {
+  trackEvent(
+    eventName: string,
+    eventProperties?: Record<string, string | string[]>,
+  ): Promise<unknown>;
+}
+
+interface TrackPageView {
+  trackPageView(path: string): Promise<unknown>;
+}
+
+interface Identify {
+  identify(userId: string, traits?: Record<string, string>): Promise<unknown>;
+}
+
+interface ProviderManager {
+  addProvider(provider: string, config: object): Promise<unknown>;
+
+  removeProvider(provider: string): void;
+}
+
+export interface AnalyticsService extends TrackPageView, TrackEvent, Identify {
+  initialize(): Promise<unknown>;
+}
+
+export type AnalyticsProviderFactory<Config extends object> = (
+  config?: Config,
+) => AnalyticsService;
+
+export interface CreateAnalyticsManagerOptions<
+  T extends string,
+  Config extends object,
+> {
+  providers: Record<T, AnalyticsProviderFactory<Config>>;
+}
+
+export interface AnalyticsManager
+  extends TrackPageView,
+    TrackEvent,
+    Identify,
+    ProviderManager {}

packages/analytics/tsconfig.json

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+{
+  "extends": "@kit/tsconfig/base.json",
+  "compilerOptions": {
+    "tsBuildInfoFile": "node_modules/.cache/tsbuildinfo.json"
+  },
+  "include": ["*.ts", "src"],
+  "exclude": ["node_modules"]
+}

packages/billing/core/README.md

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+# Billing - @kit/billing
+
+This package is responsible for managing billing and subscription related operations.
+
+Make sure the app installs the `@kit/billing` package before using it.
+
+```json
+{
+    "name": "my-app",
+    "dependencies": {
+        "@kit/billing": "*"
+    }
+}
+```

packages/billing/core/eslint.config.mjs

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+import eslintConfigBase from '@kit/eslint-config/base.js';
+
+export default eslintConfigBase;

packages/billing/core/node_modules/@kit/eslint-config

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+../../../../../tooling/eslint

packages/billing/core/node_modules/@kit/prettier-config

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+../../../../../tooling/prettier

packages/billing/core/node_modules/@kit/supabase

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+../../../../supabase

packages/billing/core/node_modules/@kit/tsconfig

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+../../../../../tooling/typescript

packages/billing/core/node_modules/@kit/ui

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+../../../../ui

packages/billing/core/node_modules/zod

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+../../../../node_modules/.pnpm/zod@3.25.56/node_modules/zod

packages/billing/core/package.json

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+{
+  "name": "@kit/billing",
+  "private": true,
+  "version": "0.1.0",
+  "scripts": {
+    "clean": "git clean -xdf .turbo node_modules",
+    "format": "prettier --check \"**/*.{ts,tsx}\"",
+    "lint": "eslint .",
+    "typecheck": "tsc --noEmit"
+  },
+  "prettier": "@kit/prettier-config",
+  "exports": {
+    ".": "./src/index.ts",
+    "./components/*": "./src/components/*",
+    "./schema": "./src/schema/index.ts",
+    "./types": "./src/types/index.ts"
+  },
+  "devDependencies": {
+    "@kit/eslint-config": "workspace:*",
+    "@kit/prettier-config": "workspace:*",
+    "@kit/supabase": "workspace:*",
+    "@kit/tsconfig": "workspace:*",
+    "@kit/ui": "workspace:*",
+    "zod": "^3.24.4"
+  },
+  "typesVersions": {
+    "*": {
+      "*": [
+        "src/*"
+      ]
+    }
+  }
+}

packages/billing/core/src/create-billing-schema.ts

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+import { z } from 'zod';
+
+export enum LineItemType {
+  Flat = 'flat',
+  PerSeat = 'per_seat',
+  Metered = 'metered',
+}
+
+const BillingIntervalSchema = z.enum(['month', 'year']);
+const LineItemTypeSchema = z.enum(['flat', 'per_seat', 'metered']);
+
+export const BillingProviderSchema = z.enum([
+  'stripe',
+  'paddle',
+  'lemon-squeezy',
+]);
+
+export const PaymentTypeSchema = z.enum(['one-time', 'recurring']);
+
+export const LineItemSchema = z
+  .object({
+    id: z
+      .string({
+        description:
+          'Unique identifier for the line item. Defined by the Provider.',
+      })
+      .min(1),
+    name: z
+      .string({
+        description: 'Name of the line item. Displayed to the user.',
+      })
+      .min(1),
+    description: z
+      .string({
+        description:
+          'Description of the line item. Displayed to the user and will replace the auto-generated description inferred' +
+          ' from the line item. This is useful if you want to provide a more detailed description to the user.',
+      })
+      .optional(),
+    cost: z
+      .number({
+        description: 'Cost of the line item. Displayed to the user.',
+      })
+      .min(0),
+    type: LineItemTypeSchema,
+    unit: z
+      .string({
+        description:
+          'Unit of the line item. Displayed to the user. Example "seat" or "GB"',
+      })
+      .optional(),
+    setupFee: z
+      .number({
+        description: `Lemon Squeezy only: If true, in addition to the cost, a setup fee will be charged.`,
+      })
+      .positive()
+      .optional(),
+    tiers: z
+      .array(
+        z.object({
+          cost: z.number().min(0),
+          upTo: z.union([z.number().min(0), z.literal('unlimited')]),
+        }),
+      )
+      .optional(),
+  })
+  .refine(
+    (data) =>
+      data.type !== LineItemType.Metered ||
+      (data.unit && data.tiers !== undefined),
+    {
+      message: 'Metered line items must have a unit and tiers',
+      path: ['type', 'unit', 'tiers'],
+    },
+  )
+  .refine(
+    (data) => {
+      if (data.type === LineItemType.Metered) {
+        return data.cost === 0;
+      }
+
+      return true;
+    },
+    {
+      message:
+        'Metered line items must have a cost of 0. Please add a different line item type for a flat fee (Stripe)',
+      path: ['type', 'cost'],
+    },
+  );
+
+export const PlanSchema = z
+  .object({
+    id: z
+      .string({
+        description: 'Unique identifier for the plan. Defined by yourself.',
+      })
+      .min(1),
+    name: z
+      .string({
+        description: 'Name of the plan. Displayed to the user.',
+      })
+      .min(1),
+    interval: BillingIntervalSchema.optional(),
+    custom: z.boolean().default(false).optional(),
+    label: z.string().min(1).optional(),
+    buttonLabel: z.string().min(1).optional(),
+    href: z.string().min(1).optional(),
+    lineItems: z.array(LineItemSchema).refine(
+      (schema) => {
+        const types = schema.map((item) => item.type);
+
+        const perSeat = types.filter(
+          (type) => type === LineItemType.PerSeat,
+        ).length;
+
+        const flat = types.filter((type) => type === LineItemType.Flat).length;
+
+        return perSeat <= 1 && flat <= 1;
+      },
+      {
+        message: 'Plans can only have one per-seat and one flat line item',
+        path: ['lineItems'],
+      },
+    ),
+    trialDays: z
+      .number({
+        description:
+          'Number of days for the trial period. Leave empty for no trial.',
+      })
+      .positive()
+      .optional(),
+    paymentType: PaymentTypeSchema,
+  })
+  .refine(
+    (data) => {
+      if (data.custom) {
+        return data.lineItems.length === 0;
+      }
+
+      return data.lineItems.length > 0;
+    },
+    {
+      message: 'Non-Custom Plans must have at least one line item',
+      path: ['lineItems'],
+    },
+  )
+  .refine(
+    (data) => {
+      if (data.custom) {
+        return data.lineItems.length === 0;
+      }
+
+      return data.lineItems.length > 0;
+    },
+    {
+      message: 'Custom Plans must have 0 line items',
+      path: ['lineItems'],
+    },
+  )
+  .refine(
+    (data) => data.paymentType !== 'one-time' || data.interval === undefined,
+    {
+      message: 'One-time plans must not have an interval',
+      path: ['paymentType', 'interval'],
+    },
+  )
+  .refine(
+    (data) => data.paymentType !== 'recurring' || data.interval !== undefined,
+    {
+      message: 'Recurring plans must have an interval',
+      path: ['paymentType', 'interval'],
+    },
+  )
+  .refine(
+    (item) => {
+      // metered line items can be shared across plans
+      const lineItems = item.lineItems.filter(
+        (item) => item.type !== LineItemType.Metered,
+      );
+
+      const ids = lineItems.map((item) => item.id);
+
+      return ids.length === new Set(ids).size;
+    },
+    {
+      message: 'Line item IDs must be unique',
+      path: ['lineItems'],
+    },
+  )
+  .refine(
+    (data) => {
+      if (data.paymentType === 'one-time') {
+        const nonFlatLineItems = data.lineItems.filter(
+          (item) => item.type !== LineItemType.Flat,
+        );
+
+        return nonFlatLineItems.length === 0;
+      }
+
+      return true;
+    },
+    {
+      message: 'One-time plans must not have non-flat line items',
+      path: ['paymentType', 'lineItems'],
+    },
+  );
+
+const ProductSchema = z
+  .object({
+    id: z
+      .string({
+        description:
+          'Unique identifier for the product. Defined by th Provider.',
+      })
+      .min(1),
+    name: z
+      .string({
+        description: 'Name of the product. Displayed to the user.',
+      })
+      .min(1),
+    description: z
+      .string({
+        description: 'Description of the product. Displayed to the user.',
+      })
+      .min(1),
+    currency: z
+      .string({
+        description: 'Currency code for the product. Displayed to the user.',
+      })
+      .min(3)
+      .max(3),
+    badge: z
+      .string({
+        description:
+          'Badge for the product. Displayed to the user. Example: "Popular"',
+      })
+      .optional(),
+    features: z
+      .array(
+        z.string({
+          description: 'Features of the product. Displayed to the user.',
+        }),
+      )
+      .nonempty(),
+    enableDiscountField: z
+      .boolean({
+        description: 'Enable discount field for the product in the checkout.',
+      })
+      .optional(),
+    highlighted: z
+      .boolean({
+        description: 'Highlight this product. Displayed to the user.',
+      })
+      .optional(),
+    hidden: z
+      .boolean({
+        description: 'Hide this product from being displayed to users.',
+      })
+      .optional(),
+    plans: z.array(PlanSchema),
+  })
+  .refine((data) => data.plans.length > 0, {
+    message: 'Products must have at least one plan',
+    path: ['plans'],
+  })
+  .refine(
+    (item) => {
+      const planIds = item.plans.map((plan) => plan.id);
+
+      return planIds.length === new Set(planIds).size;
+    },
+    {
+      message: 'Plan IDs must be unique',
+      path: ['plans'],
+    },
+  );
+
+const BillingSchema = z
+  .object({
+    provider: BillingProviderSchema,
+    products: z.array(ProductSchema).nonempty(),
+  })
+  .refine(
+    (data) => {
+      const ids = data.products.flatMap((product) =>
+        product.plans.flatMap((plan) => plan.lineItems.map((item) => item.id)),
+      );
+
+      return ids.length === new Set(ids).size;
+    },
+    {
+      message: 'Line item IDs must be unique',
+      path: ['products'],
+    },
+  )
+  .refine(
+    (schema) => {
+      if (schema.provider === 'lemon-squeezy') {
+        for (const product of schema.products) {
+          for (const plan of product.plans) {
+            if (plan.lineItems.length > 1) {
+              return false;
+            }
+          }
+        }
+      }
+
+      return true;
+    },
+    {
+      message: 'Lemon Squeezy only supports one line item per plan',
+      path: ['provider', 'products'],
+    },
+  )
+  .refine(
+    (schema) => {
+      if (schema.provider !== 'lemon-squeezy') {
+        // Check if there are any flat fee metered items
+        const setupFeeItems = schema.products.flatMap((product) =>
+          product.plans.flatMap((plan) =>
+            plan.lineItems.filter((item) => item.setupFee),
+          ),
+        );
+
+        // If there are any flat fee metered items, return an error
+        if (setupFeeItems.length > 0) {
+          return false;
+        }
+      }
+
+      return true;
+    },
+    {
+      message:
+        'Setup fee metered items are only supported by Lemon Squeezy. For Stripe and Paddle, please use a separate line item for the setup fee.',
+      path: ['products', 'plans', 'lineItems'],
+    },
+  );
+
+export function createBillingSchema(config: z.infer<typeof BillingSchema>) {
+  return BillingSchema.parse(config);
+}
+
+export type BillingConfig = z.infer<typeof BillingSchema>;
+export type ProductSchema = z.infer<typeof ProductSchema>;
+
+export function getPlanIntervals(config: z.infer<typeof BillingSchema>) {
+  const intervals = config.products
+    .flatMap((product) => product.plans.map((plan) => plan.interval))
+    .filter(Boolean);
+
+  return Array.from(new Set(intervals));
+}
+
+/**
+ * @name getPrimaryLineItem
+ * @description Get the primary line item for a plan
+ * By default, the primary line item is the first line item in the plan for Lemon Squeezy
+ * For other providers, the primary line item is the first flat line item in the plan. If there are no flat line items,
+ * the first line item is returned.
+ *
+ * @param config
+ * @param planId
+ */
+export function getPrimaryLineItem(
+  config: z.infer<typeof BillingSchema>,
+  planId: string,
+) {
+  for (const product of config.products) {
+    for (const plan of product.plans) {
+      if (plan.id === planId) {
+        // Lemon Squeezy only supports one line item per plan
+        if (config.provider === 'lemon-squeezy') {
+          return plan.lineItems[0];
+        }
+
+        const flatLineItem = plan.lineItems.find(
+          (item) => item.type === LineItemType.Flat,
+        );
+
+        if (flatLineItem) {
+          return flatLineItem;
+        }
+
+        return plan.lineItems[0];
+      }
+    }
+  }
+
+  throw new Error('Base line item not found');
+}
+
+export function getProductPlanPair(
+  config: z.infer<typeof BillingSchema>,
+  planId: string,
+) {
+  for (const product of config.products) {
+    for (const plan of product.plans) {
+      if (plan.id === planId) {
+        return { product, plan };
+      }
+    }
+  }
+
+  throw new Error('Plan not found');
+}
+
+export function getProductPlanPairByVariantId(
+  config: z.infer<typeof BillingSchema>,
+  planId: string,
+) {
+  for (const product of config.products) {
+    for (const plan of product.plans) {
+      for (const lineItem of plan.lineItems) {
+        if (lineItem.id === planId) {
+          return { product, plan };
+        }
+      }
+    }
+  }
+
+  throw new Error('Plan not found');
+}
+
+export type PlanTypeMap = Map<string, z.infer<typeof LineItemTypeSchema>>;
+
+/**
+ * @name getPlanTypesMap
+ * @description Get all line item types for all plans in the config
+ * @param config
+ */
+export function getPlanTypesMap(
+  config: z.infer<typeof BillingSchema>,
+): PlanTypeMap {
+  const planTypes: PlanTypeMap = new Map();
+
+  for (const product of config.products) {
+    for (const plan of product.plans) {
+      for (const lineItem of plan.lineItems) {
+        planTypes.set(lineItem.id, lineItem.type);
+      }
+    }
+  }
+
+  return planTypes;
+}

packages/billing/core/src/index.ts

@@ -0,0 +1,3 @@
+export * from './create-billing-schema';
+export * from './services/billing-strategy-provider.service';
+export * from './services/billing-webhook-handler.service';

packages/billing/core/src/schema/cancel-subscription-params.schema.ts

@@ -0,0 +1,6 @@
+import { z } from 'zod';
+
+export const CancelSubscriptionParamsSchema = z.object({
+  subscriptionId: z.string(),
+  invoiceNow: z.boolean().optional(),
+});

packages/billing/core/src/schema/create-biling-portal-session.schema.ts

@@ -0,0 +1,6 @@
+import { z } from 'zod';
+
+export const CreateBillingPortalSessionSchema = z.object({
+  returnUrl: z.string().url(),
+  customerId: z.string().min(1),
+});

packages/billing/core/src/schema/create-billing-checkout.schema.ts

@@ -0,0 +1,19 @@
+import { z } from 'zod';
+
+import { PlanSchema } from '../create-billing-schema';
+
+export const CreateBillingCheckoutSchema = z.object({
+  returnUrl: z.string().url(),
+  accountId: z.string().uuid(),
+  plan: PlanSchema,
+  customerId: z.string().optional(),
+  customerEmail: z.string().email().optional(),
+  enableDiscountField: z.boolean().optional(),
+  variantQuantities: z.array(
+    z.object({
+      variantId: z.string().min(1),
+      quantity: z.number(),
+    }),
+  ),
+  metadata: z.record(z.string()).optional(),
+});

packages/billing/core/src/schema/index.ts

@@ -0,0 +1,7 @@
+export * from './create-billing-checkout.schema';
+export * from './create-biling-portal-session.schema';
+export * from './retrieve-checkout-session.schema';
+export * from './cancel-subscription-params.schema';
+export * from './report-billing-usage.schema';
+export * from './update-subscription-params.schema';
+export * from './query-billing-usage.schema';

packages/billing/core/src/schema/query-billing-usage.schema.ts

@@ -0,0 +1,32 @@
+import { z } from 'zod';
+
+const TimeFilter = z.object(
+  {
+    startTime: z.number(),
+    endTime: z.number(),
+  },
+  {
+    description: `The time range to filter the usage records. Used for Stripe`,
+  },
+);
+
+const PageFilter = z.object(
+  {
+    page: z.number(),
+    size: z.number(),
+  },
+  {
+    description: `The page and size to filter the usage records. Used for LS`,
+  },
+);
+
+export const QueryBillingUsageSchema = z.object({
+  id: z.string({
+    description:
+      'The id of the usage record. For Stripe a meter ID, for LS a subscription item ID.',
+  }),
+  customerId: z.string({
+    description: 'The id of the customer in the billing system',
+  }),
+  filter: z.union([TimeFilter, PageFilter]),
+});

packages/billing/core/src/schema/report-billing-usage.schema.ts

@@ -0,0 +1,17 @@
+import { z } from 'zod';
+
+export const ReportBillingUsageSchema = z.object({
+  id: z.string({
+    description:
+      'The id of the usage record. For Stripe a customer ID, for LS a subscription item ID.',
+  }),
+  eventName: z
+    .string({
+      description: 'The name of the event that triggered the usage',
+    })
+    .optional(),
+  usage: z.object({
+    quantity: z.number(),
+    action: z.enum(['increment', 'set']).optional(),
+  }),
+});

packages/billing/core/src/schema/retrieve-checkout-session.schema.ts

@@ -0,0 +1,5 @@
+import { z } from 'zod';
+
+export const RetrieveCheckoutSessionSchema = z.object({
+  sessionId: z.string(),
+});

packages/billing/core/src/schema/update-subscription-params.schema.ts

@@ -0,0 +1,7 @@
+import { z } from 'zod';
+
+export const UpdateSubscriptionParamsSchema = z.object({
+  subscriptionId: z.string().min(1),
+  subscriptionItemId: z.string().min(1),
+  quantity: z.number().min(1),
+});

packages/billing/core/src/services/billing-strategy-provider.service.ts

@@ -0,0 +1,77 @@
+import { z } from 'zod';
+
+import {
+  CancelSubscriptionParamsSchema,
+  CreateBillingCheckoutSchema,
+  CreateBillingPortalSessionSchema,
+  QueryBillingUsageSchema,
+  ReportBillingUsageSchema,
+  RetrieveCheckoutSessionSchema,
+  UpdateSubscriptionParamsSchema,
+} from '../schema';
+import { UpsertSubscriptionParams } from '../types';
+
+export abstract class BillingStrategyProviderService {
+  abstract createBillingPortalSession(
+    params: z.infer<typeof CreateBillingPortalSessionSchema>,
+  ): Promise<{
+    url: string;
+  }>;
+
+  abstract retrieveCheckoutSession(
+    params: z.infer<typeof RetrieveCheckoutSessionSchema>,
+  ): Promise<{
+    checkoutToken: string | null;
+    status: 'complete' | 'expired' | 'open';
+    isSessionOpen: boolean;
+
+    customer: {
+      email: string | null;
+    };
+  }>;
+
+  abstract createCheckoutSession(
+    params: z.infer<typeof CreateBillingCheckoutSchema>,
+  ): Promise<{
+    checkoutToken: string;
+  }>;
+
+  abstract cancelSubscription(
+    params: z.infer<typeof CancelSubscriptionParamsSchema>,
+  ): Promise<{
+    success: boolean;
+  }>;
+
+  abstract reportUsage(
+    params: z.infer<typeof ReportBillingUsageSchema>,
+  ): Promise<{
+    success: boolean;
+  }>;
+
+  abstract queryUsage(
+    params: z.infer<typeof QueryBillingUsageSchema>,
+  ): Promise<{
+    value: number;
+  }>;
+
+  abstract updateSubscriptionItem(
+    params: z.infer<typeof UpdateSubscriptionParamsSchema>,
+  ): Promise<{
+    success: boolean;
+  }>;
+
+  abstract getPlanById(planId: string): Promise<{
+    id: string;
+    name: string;
+    interval: string;
+    amount: number;
+  }>;
+
+  abstract getSubscription(subscriptionId: string): Promise<
+    UpsertSubscriptionParams & {
+      // we can't always guarantee that the target account id will be present
+      // so we need to make it optional and let the consumer handle it
+      target_account_id: string | undefined;
+    }
+  >;
+}

packages/billing/core/src/services/billing-webhook-handler.service.ts

@@ -0,0 +1,55 @@
+import { UpsertOrderParams, UpsertSubscriptionParams } from '../types';
+
+/**
+ * @name BillingWebhookHandlerService
+ * @description Represents an abstract class for handling billing webhook events.
+ */
+export abstract class BillingWebhookHandlerService {
+  /**
+   * @name verifyWebhookSignature
+   * @description Verify the webhook signature
+   * @param request
+   */
+  abstract verifyWebhookSignature(request: Request): Promise<unknown>;
+
+  /**
+   * @name handleWebhookEvent
+   * @description Handle the webhook event from the billing provider
+   * @param event
+   * @param params
+   */
+  abstract handleWebhookEvent(
+    event: unknown,
+    params: {
+      // this method is called when a checkout session is completed
+      onCheckoutSessionCompleted: (
+        subscription: UpsertSubscriptionParams | UpsertOrderParams,
+      ) => Promise<unknown>;
+
+      // this method is called when a subscription is updated
+      onSubscriptionUpdated: (
+        subscription: UpsertSubscriptionParams,
+      ) => Promise<unknown>;
+
+      // this method is called when a subscription is deleted
+      onSubscriptionDeleted: (subscriptionId: string) => Promise<unknown>;
+
+      // this method is called when a payment is succeeded. This is used for
+      // one-time payments
+      onPaymentSucceeded: (sessionId: string) => Promise<unknown>;
+
+      // this method is called when a payment is failed. This is used for
+      // one-time payments
+      onPaymentFailed: (sessionId: string) => Promise<unknown>;
+
+      // this method is called when an invoice is paid. We don't have a specific use case for this
+      // but it's extremely common for credit-based systems
+      onInvoicePaid: (
+        subscription: UpsertSubscriptionParams,
+      ) => Promise<unknown>;
+
+      // generic handler for any event
+      onEvent?: (data: unknown) => Promise<unknown>;
+    },
+  ): Promise<unknown>;
+}

packages/billing/core/src/types/index.ts

@@ -0,0 +1,22 @@
+import { Database } from '@kit/supabase/database';
+
+export type UpsertSubscriptionParams =
+  Database['public']['Functions']['upsert_subscription']['Args'] & {
+    line_items: Array<LineItem>;
+  };
+
+interface LineItem {
+  id: string;
+  quantity: number;
+  subscription_id: string;
+  subscription_item_id: string;
+  product_id: string;
+  variant_id: string;
+  price_amount: number | null | undefined;
+  interval: string;
+  interval_count: number;
+  type: 'flat' | 'metered' | 'per_seat' | undefined;
+}
+
+export type UpsertOrderParams =
+  Database['public']['Functions']['upsert_order']['Args'];

packages/billing/core/tsconfig.json

@@ -0,0 +1,8 @@
+{
+  "extends": "@kit/tsconfig/base.json",
+  "compilerOptions": {
+    "tsBuildInfoFile": "node_modules/.cache/tsbuildinfo.json"
+  },
+  "include": ["*.ts", "src"],
+  "exclude": ["node_modules"]
+}

packages/billing/gateway/README.md

@@ -0,0 +1,3 @@
+# Billing - @kit/billing-gateway
+
+This package is responsible for handling all billing related operations. It is a gateway to the billing service.

packages/billing/gateway/eslint.config.mjs

@@ -0,0 +1,3 @@
+import eslintConfigBase from '@kit/eslint-config/base.js';
+
+export default eslintConfigBase;

packages/billing/gateway/node_modules/.bin/next

@@ -0,0 +1,17 @@
+#!/bin/sh
+basedir=$(dirname "$(echo "$0" | sed -e 's,\\,/,g')")
+
+case `uname` in
+    *CYGWIN*) basedir=`cygpath -w "$basedir"`;;
+esac
+
+if [ -z "$NODE_PATH" ]; then
+  export NODE_PATH="/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/dist/bin/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/dist/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/node_modules"
+else
+  export NODE_PATH="/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/dist/bin/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/dist/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/node_modules:$NODE_PATH"
+fi
+if [ -x "$basedir/node" ]; then
+  exec "$basedir/node"  "$basedir/../next/dist/bin/next" "$@"
+else
+  exec node  "$basedir/../next/dist/bin/next" "$@"
+fi

packages/billing/gateway/node_modules/.bin/tsc

@@ -0,0 +1,17 @@
+#!/bin/sh
+basedir=$(dirname "$(echo "$0" | sed -e 's,\\,/,g')")
+
+case `uname` in
+    *CYGWIN*) basedir=`cygpath -w "$basedir"`;;
+esac
+
+if [ -z "$NODE_PATH" ]; then
+  export NODE_PATH="/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/bin/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/node_modules"
+else
+  export NODE_PATH="/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/bin/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/node_modules:$NODE_PATH"
+fi
+if [ -x "$basedir/node" ]; then
+  exec "$basedir/node"  "$basedir/../../../../../node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/bin/tsc" "$@"
+else
+  exec node  "$basedir/../../../../../node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/bin/tsc" "$@"
+fi

packages/billing/gateway/node_modules/.bin/tsserver

@@ -0,0 +1,17 @@
+#!/bin/sh
+basedir=$(dirname "$(echo "$0" | sed -e 's,\\,/,g')")
+
+case `uname` in
+    *CYGWIN*) basedir=`cygpath -w "$basedir"`;;
+esac
+
+if [ -z "$NODE_PATH" ]; then
+  export NODE_PATH="/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/bin/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/node_modules"
+else
+  export NODE_PATH="/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/bin/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/typescript@5.8.3/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/node_modules:$NODE_PATH"
+fi
+if [ -x "$basedir/node" ]; then
+  exec "$basedir/node"  "$basedir/../../../../../node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/bin/tsserver" "$@"
+else
+  exec node  "$basedir/../../../../../node_modules/.pnpm/typescript@5.8.3/node_modules/typescript/bin/tsserver" "$@"
+fi

packages/billing/gateway/node_modules/@hookform/resolvers

@@ -0,0 +1 @@
+../../../../../node_modules/.pnpm/@hookform+resolvers@5.0.1_react-hook-form@7.57.0_react@19.1.0_/node_modules/@hookform/resolvers

packages/billing/gateway/node_modules/@kit/billing

@@ -0,0 +1 @@
+../../../core

packages/billing/gateway/node_modules/@kit/eslint-config

@@ -0,0 +1 @@
+../../../../../tooling/eslint

packages/billing/gateway/node_modules/@kit/lemon-squeezy

@@ -0,0 +1 @@
+../../../lemon-squeezy

packages/billing/gateway/node_modules/@kit/prettier-config

@@ -0,0 +1 @@
+../../../../../tooling/prettier

packages/billing/gateway/node_modules/@kit/shared

@@ -0,0 +1 @@
+../../../../shared

packages/billing/gateway/node_modules/@kit/stripe

@@ -0,0 +1 @@
+../../../stripe

packages/billing/gateway/node_modules/@kit/supabase

@@ -0,0 +1 @@
+../../../../supabase

packages/billing/gateway/node_modules/@kit/tsconfig

@@ -0,0 +1 @@
+../../../../../tooling/typescript

packages/billing/gateway/node_modules/@kit/ui

@@ -0,0 +1 @@
+../../../../ui

packages/billing/gateway/node_modules/@supabase/supabase-js

@@ -0,0 +1 @@
+../../../../../node_modules/.pnpm/@supabase+supabase-js@2.49.4/node_modules/@supabase/supabase-js

packages/billing/gateway/node_modules/@types/react

@@ -0,0 +1 @@
+../../../../../node_modules/.pnpm/@types+react@19.1.4/node_modules/@types/react

packages/billing/gateway/node_modules/date-fns

@@ -0,0 +1 @@
+../../../../node_modules/.pnpm/date-fns@4.1.0/node_modules/date-fns

packages/billing/gateway/node_modules/lucide-react

@@ -0,0 +1 @@
+../../../../node_modules/.pnpm/lucide-react@0.510.0_react@19.1.0/node_modules/lucide-react

packages/billing/gateway/node_modules/next

@@ -0,0 +1 @@
+../../../../node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next

packages/billing/gateway/node_modules/react

@@ -0,0 +1 @@
+../../../../node_modules/.pnpm/react@19.1.0/node_modules/react

packages/billing/gateway/node_modules/react-hook-form

@@ -0,0 +1 @@
+../../../../node_modules/.pnpm/react-hook-form@7.57.0_react@19.1.0/node_modules/react-hook-form

packages/billing/gateway/node_modules/react-i18next

@@ -0,0 +1 @@
+../../../../node_modules/.pnpm/react-i18next@15.5.2_i18next@25.1.3_typescript@5.8.3__react-dom@19.1.0_react@19.1.0__react@19.1.0_typescript@5.8.3/node_modules/react-i18next

packages/billing/gateway/node_modules/zod

@@ -0,0 +1 @@
+../../../../node_modules/.pnpm/zod@3.25.56/node_modules/zod

packages/billing/gateway/package.json

@@ -0,0 +1,46 @@
+{
+  "name": "@kit/billing-gateway",
+  "private": true,
+  "version": "0.1.0",
+  "scripts": {
+    "clean": "git clean -xdf .turbo node_modules",
+    "format": "prettier --check \"**/*.{ts,tsx}\"",
+    "lint": "eslint .",
+    "typecheck": "tsc --noEmit"
+  },
+  "prettier": "@kit/prettier-config",
+  "exports": {
+    ".": "./src/index.ts",
+    "./components": "./src/components/index.ts",
+    "./checkout": "./src/components/embedded-checkout.tsx",
+    "./marketing": "./src/components/marketing.tsx"
+  },
+  "devDependencies": {
+    "@hookform/resolvers": "^5.0.1",
+    "@kit/billing": "workspace:*",
+    "@kit/eslint-config": "workspace:*",
+    "@kit/lemon-squeezy": "workspace:*",
+    "@kit/prettier-config": "workspace:*",
+    "@kit/shared": "workspace:*",
+    "@kit/stripe": "workspace:*",
+    "@kit/supabase": "workspace:*",
+    "@kit/tsconfig": "workspace:*",
+    "@kit/ui": "workspace:*",
+    "@supabase/supabase-js": "2.49.4",
+    "@types/react": "19.1.4",
+    "date-fns": "^4.1.0",
+    "lucide-react": "^0.510.0",
+    "next": "15.3.2",
+    "react": "19.1.0",
+    "react-hook-form": "^7.56.3",
+    "react-i18next": "^15.5.1",
+    "zod": "^3.24.4"
+  },
+  "typesVersions": {
+    "*": {
+      "*": [
+        "src/*"
+      ]
+    }
+  }
+}

packages/billing/gateway/src/components/billing-portal-card.tsx

@@ -0,0 +1,41 @@
+'use client';
+
+import { ArrowUpRight } from 'lucide-react';
+
+import { Button } from '@kit/ui/button';
+import {
+  Card,
+  CardContent,
+  CardDescription,
+  CardHeader,
+  CardTitle,
+} from '@kit/ui/card';
+import { Trans } from '@kit/ui/trans';
+
+export function BillingPortalCard() {
+  return (
+    <Card>
+      <CardHeader>
+        <CardTitle>
+          <Trans i18nKey="billing:billingPortalCardTitle" />
+        </CardTitle>
+
+        <CardDescription>
+          <Trans i18nKey="billing:billingPortalCardDescription" />
+        </CardDescription>
+      </CardHeader>
+
+      <CardContent className={'space-y-2'}>
+        <div>
+          <Button data-test={'manage-billing-redirect-button'}>
+            <span>
+              <Trans i18nKey="billing:billingPortalCardButton" />
+            </span>
+
+            <ArrowUpRight className={'h-4'} />
+          </Button>
+        </div>
+      </CardContent>
+    </Card>
+  );
+}

packages/billing/gateway/src/components/billing-session-status.tsx

@@ -0,0 +1,72 @@
+import Link from 'next/link';
+
+import { Check, ChevronRight } from 'lucide-react';
+
+import { Button } from '@kit/ui/button';
+import { Heading } from '@kit/ui/heading';
+import { Trans } from '@kit/ui/trans';
+
+/**
+ * Retrieves the session status for a Stripe checkout session.
+ * Since we should only arrive here for a successful checkout, we only check
+ * for the `paid` status.
+ **/
+export function BillingSessionStatus({
+  customerEmail,
+  redirectPath,
+}: React.PropsWithChildren<{
+  customerEmail: string;
+  redirectPath: string;
+}>) {
+  return (
+    <section
+      data-test={'payment-return-success'}
+      className={
+        'fade-in dark:border-border mx-auto max-w-xl rounded-xl border border-transparent p-16 xl:drop-shadow-2xl' +
+        ' bg-background animate-in slide-in-from-bottom-8 ease-out' +
+        ' zoom-in-50 dark:shadow-primary/20 duration-1000 dark:shadow-2xl'
+      }
+    >
+      <div
+        className={
+          'flex flex-col items-center justify-center space-y-6 text-center'
+        }
+      >
+        <Check
+          className={
+            'h-16 w-16 rounded-full bg-green-500 p-1 text-white ring-8' +
+            ' ring-green-500/30 dark:ring-green-500/50'
+          }
+        />
+
+        <Heading level={3}>
+          <span className={'mr-4 font-semibold'}>
+            <Trans i18nKey={'billing:checkoutSuccessTitle'} />
+          </span>
+          🎉
+        </Heading>
+
+        <div className={'text-muted-foreground flex flex-col space-y-4'}>
+          <p>
+            <Trans
+              i18nKey={'billing:checkoutSuccessDescription'}
+              values={{ customerEmail }}
+            />
+          </p>
+        </div>
+
+        <div>
+          <Button data-test={'checkout-success-back-link'} asChild>
+            <Link href={redirectPath}>
+              <span>
+                <Trans i18nKey={'billing:checkoutSuccessBackButton'} />
+              </span>
+
+              <ChevronRight className={'h-4'} />
+            </Link>
+          </Button>
+        </div>
+      </div>
+    </section>
+  );
+}

packages/billing/gateway/src/components/current-lifetime-order-card.tsx

@@ -0,0 +1,94 @@
+import { BadgeCheck } from 'lucide-react';
+
+import { BillingConfig, getProductPlanPairByVariantId } from '@kit/billing';
+import { Tables } from '@kit/supabase/database';
+import {
+  Card,
+  CardContent,
+  CardDescription,
+  CardHeader,
+  CardTitle,
+} from '@kit/ui/card';
+import { Trans } from '@kit/ui/trans';
+
+import { CurrentPlanBadge } from './current-plan-badge';
+import { LineItemDetails } from './line-item-details';
+
+type Order = Tables<'orders'>;
+type LineItem = Tables<'order_items'>;
+
+interface Props {
+  order: Order & {
+    items: LineItem[];
+  };
+
+  config: BillingConfig;
+}
+
+export function CurrentLifetimeOrderCard({
+  order,
+  config,
+}: React.PropsWithChildren<Props>) {
+  const lineItems = order.items;
+  const firstLineItem = lineItems[0];
+
+  if (!firstLineItem) {
+    throw new Error('No line items found in subscription');
+  }
+
+  const { product, plan } = getProductPlanPairByVariantId(
+    config,
+    firstLineItem.variant_id,
+  );
+
+  if (!product || !plan) {
+    throw new Error(
+      'Product or plan not found. Did you forget to add it to the billing config?',
+    );
+  }
+
+  const productLineItems = plan.lineItems;
+
+  return (
+    <Card>
+      <CardHeader>
+        <CardTitle>
+          <Trans i18nKey="billing:planCardTitle" />
+        </CardTitle>
+
+        <CardDescription>
+          <Trans i18nKey="billing:planCardDescription" />
+        </CardDescription>
+      </CardHeader>
+
+      <CardContent className={'gap-y-4 text-sm'}>
+        <div className={'flex flex-col space-y-1'}>
+          <div className={'flex items-center gap-x-3 text-lg font-semibold'}>
+            <BadgeCheck
+              className={
+                's-6 fill-green-500 text-white dark:fill-white dark:text-black'
+              }
+            />
+
+            <span>{product.name}</span>
+
+            <CurrentPlanBadge status={order.status} />
+          </div>
+        </div>
+
+        <div>
+          <div className="flex flex-col gap-y-1">
+            <span className="font-semibold">
+              <Trans i18nKey="billing:detailsLabel" />
+            </span>
+
+            <LineItemDetails
+              lineItems={productLineItems}
+              currency={order.currency}
+            />
+          </div>
+        </div>
+      </CardContent>
+    </Card>
+  );
+}

packages/billing/gateway/src/components/current-plan-alert.tsx

@@ -0,0 +1,54 @@
+import { Enums } from '@kit/supabase/database';
+import { Alert, AlertDescription, AlertTitle } from '@kit/ui/alert';
+import { Trans } from '@kit/ui/trans';
+
+export function CurrentPlanAlert(
+  props: React.PropsWithoutRef<{
+    status: Enums<'subscription_status'>;
+  }>,
+) {
+  let variant: 'success' | 'warning' | 'destructive';
+  const prefix = 'billing:status';
+
+  const text = `${prefix}.${props.status}.description`;
+  const title = `${prefix}.${props.status}.heading`;
+
+  switch (props.status) {
+    case 'active':
+      variant = 'success';
+      break;
+    case 'trialing':
+      variant = 'success';
+      break;
+    case 'past_due':
+      variant = 'destructive';
+      break;
+    case 'canceled':
+      variant = 'destructive';
+      break;
+    case 'unpaid':
+      variant = 'destructive';
+      break;
+    case 'incomplete':
+      variant = 'warning';
+      break;
+    case 'incomplete_expired':
+      variant = 'destructive';
+      break;
+    case 'paused':
+      variant = 'warning';
+      break;
+  }
+
+  return (
+    <Alert variant={variant}>
+      <AlertTitle>
+        <Trans i18nKey={title} />
+      </AlertTitle>
+
+      <AlertDescription>
+        <Trans i18nKey={text} />
+      </AlertDescription>
+    </Alert>
+  );
+}

packages/billing/gateway/src/components/current-plan-badge.tsx

@@ -0,0 +1,50 @@
+import { Enums } from '@kit/supabase/database';
+import { Badge } from '@kit/ui/badge';
+import { Trans } from '@kit/ui/trans';
+
+type Status = Enums<'subscription_status'> | Enums<'payment_status'>;
+
+export function CurrentPlanBadge(
+  props: React.PropsWithoutRef<{
+    status: Status;
+  }>,
+) {
+  let variant: 'success' | 'warning' | 'destructive';
+  const text = `billing:status.${props.status}.badge`;
+
+  switch (props.status) {
+    case 'active':
+    case 'succeeded':
+      variant = 'success';
+      break;
+    case 'trialing':
+      variant = 'success';
+      break;
+    case 'past_due':
+    case 'failed':
+      variant = 'destructive';
+      break;
+    case 'canceled':
+      variant = 'destructive';
+      break;
+    case 'unpaid':
+      variant = 'destructive';
+      break;
+    case 'incomplete':
+    case 'pending':
+      variant = 'warning';
+      break;
+    case 'incomplete_expired':
+      variant = 'destructive';
+      break;
+    case 'paused':
+      variant = 'warning';
+      break;
+  }
+
+  return (
+    <Badge data-test={'current-plan-card-status-badge'} variant={variant}>
+      <Trans i18nKey={text} />
+    </Badge>
+  );
+}

packages/billing/gateway/src/components/current-subscription-card.tsx

@@ -0,0 +1,149 @@
+import { formatDate } from 'date-fns';
+import { BadgeCheck } from 'lucide-react';
+
+import { BillingConfig, getProductPlanPairByVariantId } from '@kit/billing';
+import { Tables } from '@kit/supabase/database';
+import { Alert, AlertDescription, AlertTitle } from '@kit/ui/alert';
+import {
+  Card,
+  CardContent,
+  CardDescription,
+  CardHeader,
+  CardTitle,
+} from '@kit/ui/card';
+import { If } from '@kit/ui/if';
+import { Trans } from '@kit/ui/trans';
+
+import { CurrentPlanAlert } from './current-plan-alert';
+import { CurrentPlanBadge } from './current-plan-badge';
+import { LineItemDetails } from './line-item-details';
+
+type Subscription = Tables<'subscriptions'>;
+type LineItem = Tables<'subscription_items'>;
+
+interface Props {
+  subscription: Subscription & {
+    items: LineItem[];
+  };
+
+  config: BillingConfig;
+}
+
+export function CurrentSubscriptionCard({
+  subscription,
+  config,
+}: React.PropsWithChildren<Props>) {
+  const lineItems = subscription.items;
+  const firstLineItem = lineItems[0];
+
+  if (!firstLineItem) {
+    throw new Error('No line items found in subscription');
+  }
+
+  const { product, plan } = getProductPlanPairByVariantId(
+    config,
+    firstLineItem.variant_id,
+  );
+
+  if (!product || !plan) {
+    throw new Error(
+      'Product or plan not found. Did you forget to add it to the billing config?',
+    );
+  }
+
+  const productLineItems = plan.lineItems;
+
+  return (
+    <Card>
+      <CardHeader>
+        <CardTitle>
+          <Trans i18nKey="billing:planCardTitle" />
+        </CardTitle>
+
+        <CardDescription>
+          <Trans i18nKey="billing:planCardDescription" />
+        </CardDescription>
+      </CardHeader>
+
+      <CardContent className={'space-y-4 border-t pt-4 text-sm'}>
+        <div className={'flex flex-col space-y-1'}>
+          <div className={'flex items-center gap-x-3 text-lg font-semibold'}>
+            <BadgeCheck
+              className={
+                's-6 fill-green-500 text-white dark:fill-white dark:text-black'
+              }
+            />
+
+            <span data-test={'current-plan-card-product-name'}>
+              <Trans i18nKey={product.name} defaults={product.name} />
+            </span>
+
+            <CurrentPlanBadge status={subscription.status} />
+          </div>
+
+          <div>
+            <p className={'text-muted-foreground'}>
+              <Trans
+                i18nKey={product.description}
+                defaults={product.description}
+              />
+            </p>
+          </div>
+        </div>
+
+        {/*
+         Only show the alert if the subscription requires action
+          (e.g. trial ending soon, subscription canceled, etc.)
+        */}
+        <If condition={!subscription.active}>
+          <div data-test={'current-plan-card-status-alert'}>
+            <CurrentPlanAlert status={subscription.status} />
+          </div>
+        </If>
+
+        <If condition={subscription.status === 'trialing'}>
+          <div className="flex flex-col gap-y-1">
+            <span className="font-semibold">
+              <Trans i18nKey="billing:trialEndsOn" />
+            </span>
+
+            <div className={'text-muted-foreground'}>
+              <span>
+                {subscription.trial_ends_at
+                  ? formatDate(subscription.trial_ends_at, 'P')
+                  : ''}
+              </span>
+            </div>
+          </div>
+        </If>
+
+        <If condition={subscription.cancel_at_period_end}>
+          <Alert variant={'warning'}>
+            <AlertTitle>
+              <Trans i18nKey="billing:subscriptionCancelled" />
+            </AlertTitle>
+
+            <AlertDescription>
+              <Trans i18nKey="billing:cancelSubscriptionDate" />:
+              <span className={'ml-1'}>
+                {formatDate(subscription.period_ends_at ?? '', 'P')}
+              </span>
+            </AlertDescription>
+          </Alert>
+        </If>
+
+        <div className="flex flex-col gap-y-1">
+          <span className="font-semibold">
+            <Trans i18nKey="billing:detailsLabel" />
+          </span>
+
+          <LineItemDetails
+            lineItems={productLineItems}
+            currency={subscription.currency}
+            selectedInterval={firstLineItem.interval}
+          />
+        </div>
+      </CardContent>
+    </Card>
+  );
+}

packages/billing/gateway/src/components/embedded-checkout.tsx

@@ -0,0 +1,115 @@
+import { Suspense, forwardRef, lazy, memo, useMemo } from 'react';
+
+import { Enums } from '@kit/supabase/database';
+import { LoadingOverlay } from '@kit/ui/loading-overlay';
+
+type BillingProvider = Enums<'billing_provider'>;
+
+const Fallback = <LoadingOverlay fullPage={false} />;
+
+export function EmbeddedCheckout(
+  props: React.PropsWithChildren<{
+    checkoutToken: string;
+    provider: BillingProvider;
+    onClose?: () => void;
+  }>,
+) {
+  const CheckoutComponent = useMemo(
+    () => loadCheckoutComponent(props.provider),
+    [props.provider],
+  );
+
+  return (
+    <>
+      <CheckoutComponent
+        onClose={props.onClose}
+        checkoutToken={props.checkoutToken}
+      />
+
+      <BlurryBackdrop />
+    </>
+  );
+}
+
+function loadCheckoutComponent(provider: BillingProvider) {
+  switch (provider) {
+    case 'stripe': {
+      return buildLazyComponent(() => {
+        return import('@kit/stripe/components').then(({ StripeCheckout }) => {
+          return {
+            default: StripeCheckout,
+          };
+        });
+      });
+    }
+
+    case 'lemon-squeezy': {
+      return buildLazyComponent(() => {
+        return import('@kit/lemon-squeezy/components').then(
+          ({ LemonSqueezyEmbeddedCheckout }) => {
+            return {
+              default: LemonSqueezyEmbeddedCheckout,
+            };
+          },
+        );
+      });
+    }
+
+    case 'paddle': {
+      throw new Error('Paddle is not yet supported');
+    }
+
+    default:
+      throw new Error(`Unsupported provider: ${provider as string}`);
+  }
+}
+
+function buildLazyComponent<
+  Component extends React.ComponentType<{
+    onClose: (() => unknown) | undefined;
+    checkoutToken: string;
+  }>,
+>(
+  load: () => Promise<{
+    default: Component;
+  }>,
+  fallback = Fallback,
+) {
+  let LoadedComponent: ReturnType<typeof lazy<Component>> | null = null;
+
+  const LazyComponent = forwardRef<
+    React.ElementRef<'div'>,
+    {
+      onClose: (() => unknown) | undefined;
+      checkoutToken: string;
+    }
+  >(function LazyDynamicComponent(props, ref) {
+    if (!LoadedComponent) {
+      LoadedComponent = lazy(load);
+    }
+
+    return (
+      <Suspense fallback={fallback}>
+        {/* @ts-expect-error: weird TS */}
+        <LoadedComponent
+          onClose={props.onClose}
+          checkoutToken={props.checkoutToken}
+          ref={ref}
+        />
+      </Suspense>
+    );
+  });
+
+  return memo(LazyComponent);
+}
+
+function BlurryBackdrop() {
+  return (
+    <div
+      className={
+        'bg-background/30 fixed left-0 top-0 w-full backdrop-blur-sm' +
+        ' !m-0 h-full'
+      }
+    />
+  );
+}

packages/billing/gateway/src/components/index.ts

@@ -0,0 +1,5 @@
+export * from './plan-picker';
+export * from './current-subscription-card';
+export * from './current-lifetime-order-card';
+export * from './billing-session-status';
+export * from './billing-portal-card';

packages/billing/gateway/src/components/line-item-details.tsx

@@ -0,0 +1,304 @@
+'use client';
+
+import { PlusSquare } from 'lucide-react';
+import { useTranslation } from 'react-i18next';
+import { z } from 'zod';
+
+import type { LineItemSchema } from '@kit/billing';
+import { formatCurrency } from '@kit/shared/utils';
+import { If } from '@kit/ui/if';
+import { Trans } from '@kit/ui/trans';
+import { cn } from '@kit/ui/utils';
+
+const className = 'flex text-secondary-foreground items-center text-sm';
+
+export function LineItemDetails(
+  props: React.PropsWithChildren<{
+    lineItems: z.infer<typeof LineItemSchema>[];
+    currency: string;
+    selectedInterval?: string | undefined;
+  }>,
+) {
+  const locale = useTranslation().i18n.language;
+  const currencyCode = props?.currency.toLowerCase();
+
+  return (
+    <div className={'flex flex-col space-y-1'}>
+      {props.lineItems.map((item, index) => {
+        // If the item has a description, we render it as a simple text
+        // and pass the item as values to the translation so we can use
+        // the item properties in the translation.
+        if (item.description) {
+          return (
+            <div key={index} className={className}>
+              <span className={'flex items-center space-x-1.5'}>
+                <PlusSquare className={'w-4'} />
+
+                <Trans
+                  i18nKey={item.description}
+                  values={item}
+                  defaults={item.description}
+                />
+              </span>
+            </div>
+          );
+        }
+
+        const SetupFee = () => (
+          <If condition={item.setupFee}>
+            <div className={className}>
+              <span className={'flex items-center space-x-1'}>
+                <PlusSquare className={'w-3'} />
+
+                <span>
+                  <Trans
+                    i18nKey={'billing:setupFee'}
+                    values={{
+                      setupFee: formatCurrency({
+                        currencyCode,
+                        value: item.setupFee as number,
+                        locale,
+                      }),
+                    }}
+                  />
+                </span>
+              </span>
+            </div>
+          </If>
+        );
+
+        const FlatFee = () => (
+          <div className={'flex flex-col'}>
+            <div className={cn(className, 'space-x-1')}>
+              <span className={'flex items-center space-x-1'}>
+                <span className={'flex items-center space-x-1.5'}>
+                  <PlusSquare className={'w-3'} />
+
+                  <span>
+                    <Trans i18nKey={'billing:basePlan'} />
+                  </span>
+                </span>
+
+                <span>
+                  <If
+                    condition={props.selectedInterval}
+                    fallback={<Trans i18nKey={'billing:lifetime'} />}
+                  >
+                    (
+                    <Trans
+                      i18nKey={`billing:billingInterval.${props.selectedInterval}`}
+                    />
+                    )
+                  </If>
+                </span>
+              </span>
+
+              <span>-</span>
+
+              <span className={'text-xs font-semibold'}>
+                {formatCurrency({
+                  currencyCode,
+                  value: item.cost,
+                  locale,
+                })}
+              </span>
+            </div>
+
+            <SetupFee />
+
+            <If condition={item.tiers?.length}>
+              <span className={'flex items-center space-x-1.5'}>
+                <PlusSquare className={'w-3'} />
+
+                <span className={'flex gap-x-2 text-sm'}>
+                  <span>
+                    <Trans
+                      i18nKey={'billing:perUnit'}
+                      values={{
+                        unit: item.unit,
+                      }}
+                    />
+                  </span>
+                </span>
+              </span>
+
+              <Tiers item={item} currency={props.currency} />
+            </If>
+          </div>
+        );
+
+        const PerSeat = () => (
+          <div key={index} className={'flex flex-col'}>
+            <div className={className}>
+              <span className={'flex items-center space-x-1.5'}>
+                <PlusSquare className={'w-3'} />
+
+                <span>
+                  <Trans i18nKey={'billing:perTeamMember'} />
+                </span>
+
+                <span>-</span>
+
+                <If condition={!item.tiers?.length}>
+                  <span className={'font-semibold'}>
+                    {formatCurrency({
+                      currencyCode,
+                      value: item.cost,
+                      locale,
+                    })}
+                  </span>
+                </If>
+              </span>
+            </div>
+
+            <SetupFee />
+
+            <If condition={item.tiers?.length}>
+              <Tiers item={item} currency={props.currency} />
+            </If>
+          </div>
+        );
+
+        const Metered = () => (
+          <div key={index} className={'flex flex-col'}>
+            <div className={className}>
+              <span className={'flex items-center space-x-1'}>
+                <span className={'flex items-center space-x-1.5'}>
+                  <PlusSquare className={'w-3'} />
+
+                  <span className={'flex space-x-1'}>
+                    <span>
+                      <Trans
+                        i18nKey={'billing:perUnit'}
+                        values={{
+                          unit: item.unit,
+                        }}
+                      />
+                    </span>
+                  </span>
+                </span>
+              </span>
+
+              {/* If there are no tiers, there is a flat cost for usage */}
+              <If condition={!item.tiers?.length}>
+                <span className={'font-semibold'}>
+                  {formatCurrency({
+                    currencyCode,
+                    value: item.cost,
+                    locale,
+                  })}
+                </span>
+              </If>
+            </div>
+
+            <SetupFee />
+
+            {/* If there are tiers, we render them as a list */}
+            <If condition={item.tiers?.length}>
+              <Tiers item={item} currency={props.currency} />
+            </If>
+          </div>
+        );
+
+        switch (item.type) {
+          case 'flat':
+            return <FlatFee key={item.id} />;
+
+          case 'per_seat':
+            return <PerSeat key={item.id} />;
+
+          case 'metered': {
+            return <Metered key={item.id} />;
+          }
+        }
+      })}
+    </div>
+  );
+}
+
+function Tiers({
+  currency,
+  item,
+}: {
+  currency: string;
+  item: z.infer<typeof LineItemSchema>;
+}) {
+  const unit = item.unit;
+  const locale = useTranslation().i18n.language;
+
+  const tiers = item.tiers?.map((tier, index) => {
+    const tiersLength = item.tiers?.length ?? 0;
+    const previousTier = item.tiers?.[index - 1];
+    const isLastTier = tier.upTo === 'unlimited';
+
+    const previousTierFrom =
+      previousTier?.upTo === 'unlimited'
+        ? 'unlimited'
+        : previousTier === undefined
+          ? 0
+          : previousTier.upTo + 1 || 0;
+
+    const upTo = tier.upTo;
+    const isIncluded = tier.cost === 0;
+
+    return (
+      <span className={'text-secondary-foreground text-xs'} key={index}>
+        <span>-</span>{' '}
+        <If condition={isLastTier}>
+          <span className={'font-bold'}>
+            {formatCurrency({
+              currencyCode: currency.toLowerCase(),
+              value: tier.cost,
+              locale,
+            })}
+          </span>{' '}
+          <If condition={tiersLength > 1}>
+            <span>
+              <Trans
+                i18nKey={'billing:andAbove'}
+                values={{
+                  unit,
+                  previousTier: (previousTierFrom as number) - 1,
+                }}
+              />
+            </span>
+          </If>
+          <If condition={tiersLength === 1}>
+            <span>
+              <Trans
+                i18nKey={'billing:forEveryUnit'}
+                values={{
+                  unit,
+                }}
+              />
+            </span>
+          </If>
+        </If>{' '}
+        <If condition={!isLastTier}>
+          <If condition={isIncluded}>
+            <span>
+              <Trans i18nKey={'billing:includedUpTo'} values={{ unit, upTo }} />
+            </span>
+          </If>{' '}
+          <If condition={!isIncluded}>
+            <span className={'font-bold'}>
+              {formatCurrency({
+                currencyCode: currency.toLowerCase(),
+                value: tier.cost,
+                locale,
+              })}
+            </span>{' '}
+            <span>
+              <Trans
+                i18nKey={'billing:fromPreviousTierUpTo'}
+                values={{ previousTierFrom, unit, upTo }}
+              />
+            </span>
+          </If>
+        </If>
+      </span>
+    );
+  });
+
+  return <div className={'my-1 flex flex-col space-y-1.5'}>{tiers}</div>;
+}

packages/billing/gateway/src/components/marketing.tsx

@@ -0,0 +1 @@
+export * from './pricing-table';

packages/billing/gateway/src/components/plan-cost-display.tsx

@@ -0,0 +1,98 @@
+'use client';
+
+import { useMemo } from 'react';
+
+import { useTranslation } from 'react-i18next';
+import { z } from 'zod';
+
+import type { LineItemSchema } from '@kit/billing';
+import { formatCurrency } from '@kit/shared/utils';
+import { Trans } from '@kit/ui/trans';
+
+type PlanCostDisplayProps = {
+  primaryLineItem: z.infer<typeof LineItemSchema>;
+  currencyCode: string;
+  interval?: string;
+  alwaysDisplayMonthlyPrice?: boolean;
+  className?: string;
+};
+
+/**
+ * @name PlanCostDisplay
+ * @description
+ * This component is used to display the cost of a plan. It will handle
+ * the display of the cost for metered plans by using the lowest tier using the format "Starting at {price} {unit}"
+ */
+export function PlanCostDisplay({
+  primaryLineItem,
+  currencyCode,
+  interval,
+  alwaysDisplayMonthlyPrice = true,
+  className,
+}: PlanCostDisplayProps) {
+  const { i18n } = useTranslation();
+
+  const { shouldDisplayTier, lowestTier, tierTranslationKey, displayCost } =
+    useMemo(() => {
+      const shouldDisplayTier =
+        primaryLineItem.type === 'metered' &&
+        Array.isArray(primaryLineItem.tiers) &&
+        primaryLineItem.tiers.length > 0;
+
+      const isMultiTier =
+        Array.isArray(primaryLineItem.tiers) &&
+        primaryLineItem.tiers.length > 1;
+
+      const lowestTier = primaryLineItem.tiers?.reduce((acc, curr) => {
+        if (acc && acc.cost < curr.cost) {
+          return acc;
+        }
+        return curr;
+      }, primaryLineItem.tiers?.[0]);
+
+      const isYearlyPricing = interval === 'year';
+
+      const cost =
+        isYearlyPricing && alwaysDisplayMonthlyPrice
+          ? Number(primaryLineItem.cost / 12)
+          : primaryLineItem.cost;
+
+      return {
+        shouldDisplayTier,
+        isMultiTier,
+        lowestTier,
+        tierTranslationKey: isMultiTier
+          ? 'billing:startingAtPriceUnit'
+          : 'billing:priceUnit',
+        displayCost: cost,
+      };
+    }, [primaryLineItem, interval, alwaysDisplayMonthlyPrice]);
+
+  if (shouldDisplayTier) {
+    const formattedCost = formatCurrency({
+      currencyCode: currencyCode.toLowerCase(),
+      value: lowestTier?.cost ?? 0,
+      locale: i18n.language,
+    });
+
+    return (
+      <span className={'text-lg'}>
+        <Trans
+          i18nKey={tierTranslationKey}
+          values={{
+            price: formattedCost,
+            unit: primaryLineItem.unit,
+          }}
+        />
+      </span>
+    );
+  }
+
+  const formattedCost = formatCurrency({
+    currencyCode: currencyCode.toLowerCase(),
+    value: displayCost,
+    locale: i18n.language,
+  });
+
+  return <span className={className}>{formattedCost}</span>;
+}

packages/billing/gateway/src/components/plan-picker.tsx

@@ -0,0 +1,500 @@
+'use client';
+
+import { useMemo } from 'react';
+
+import { zodResolver } from '@hookform/resolvers/zod';
+import { ArrowRight, CheckCircle } from 'lucide-react';
+import { useForm, useWatch } from 'react-hook-form';
+import { useTranslation } from 'react-i18next';
+import { z } from 'zod';
+
+import {
+  BillingConfig,
+  type LineItemSchema,
+  getPlanIntervals,
+  getPrimaryLineItem,
+  getProductPlanPair,
+} from '@kit/billing';
+import { Badge } from '@kit/ui/badge';
+import { Button } from '@kit/ui/button';
+import {
+  Form,
+  FormControl,
+  FormField,
+  FormItem,
+  FormLabel,
+  FormMessage,
+} from '@kit/ui/form';
+import { If } from '@kit/ui/if';
+import { Label } from '@kit/ui/label';
+import {
+  RadioGroup,
+  RadioGroupItem,
+  RadioGroupItemLabel,
+} from '@kit/ui/radio-group';
+import { Separator } from '@kit/ui/separator';
+import { Trans } from '@kit/ui/trans';
+import { cn } from '@kit/ui/utils';
+
+import { LineItemDetails } from './line-item-details';
+import { PlanCostDisplay } from './plan-cost-display';
+
+export function PlanPicker(
+  props: React.PropsWithChildren<{
+    config: BillingConfig;
+    onSubmit: (data: { planId: string; productId: string }) => void;
+    canStartTrial?: boolean;
+    pending?: boolean;
+  }>,
+) {
+  const { t } = useTranslation(`billing`);
+
+  const intervals = useMemo(
+    () => getPlanIntervals(props.config),
+    [props.config],
+  ) as string[];
+
+  const form = useForm({
+    reValidateMode: 'onChange',
+    mode: 'onChange',
+    resolver: zodResolver(
+      z
+        .object({
+          planId: z.string(),
+          productId: z.string(),
+          interval: z.string().optional(),
+        })
+        .refine(
+          (data) => {
+            try {
+              const { product, plan } = getProductPlanPair(
+                props.config,
+                data.planId,
+              );
+
+              return product && plan;
+            } catch {
+              return false;
+            }
+          },
+          { message: t('noPlanChosen'), path: ['planId'] },
+        ),
+    ),
+    defaultValues: {
+      interval: intervals[0],
+      planId: '',
+      productId: '',
+    },
+  });
+
+  const selectedInterval = useWatch({
+    name: 'interval',
+    control: form.control,
+  });
+
+  const planId = form.getValues('planId');
+
+  const { plan: selectedPlan, product: selectedProduct } = useMemo(() => {
+    try {
+      return getProductPlanPair(props.config, planId);
+    } catch {
+      return {
+        plan: null,
+        product: null,
+      };
+    }
+  }, [props.config, planId]);
+
+  // display the period picker if the selected plan is recurring or if no plan is selected
+  const isRecurringPlan =
+    selectedPlan?.paymentType === 'recurring' || !selectedPlan;
+
+  // Always filter out hidden products
+  const visibleProducts = props.config.products.filter(
+    (product) => !product.hidden,
+  );
+
+  return (
+    <Form {...form}>
+      <div
+        className={'flex flex-col gap-y-4 lg:flex-row lg:gap-x-4 lg:gap-y-0'}
+      >
+        <form
+          className={'flex w-full max-w-xl flex-col gap-y-8'}
+          onSubmit={form.handleSubmit(props.onSubmit)}
+        >
+          <If condition={intervals.length}>
+            <div
+              className={cn('transition-all', {
+                ['pointer-events-none opacity-50']: !isRecurringPlan,
+              })}
+            >
+              <FormField
+                name={'interval'}
+                render={({ field }) => {
+                  return (
+                    <FormItem className={'flex flex-col gap-4'}>
+                      <FormLabel htmlFor={'plan-picker-id'}>
+                        <Trans i18nKey={'common:billingInterval.label'} />
+                      </FormLabel>
+
+                      <FormControl id={'plan-picker-id'}>
+                        <RadioGroup name={field.name} value={field.value}>
+                          <div className={'flex space-x-2.5'}>
+                            {intervals.map((interval) => {
+                              const selected = field.value === interval;
+
+                              return (
+                                <label
+                                  htmlFor={interval}
+                                  key={interval}
+                                  className={cn(
+                                    'focus-within:border-primary flex items-center gap-x-2.5 rounded-md border px-2.5 py-2 transition-colors',
+                                    {
+                                      ['bg-muted border-input']: selected,
+                                      ['hover:border-input border-transparent']:
+                                        !selected,
+                                    },
+                                  )}
+                                >
+                                  <RadioGroupItem
+                                    id={interval}
+                                    value={interval}
+                                    onClick={() => {
+                                      form.setValue('interval', interval, {
+                                        shouldValidate: true,
+                                      });
+
+                                      if (selectedProduct) {
+                                        const plan = selectedProduct.plans.find(
+                                          (item) => item.interval === interval,
+                                        );
+
+                                        form.setValue(
+                                          'planId',
+                                          plan?.id ?? '',
+                                          {
+                                            shouldValidate: true,
+                                            shouldDirty: true,
+                                            shouldTouch: true,
+                                          },
+                                        );
+                                      }
+                                    }}
+                                  />
+
+                                  <span
+                                    className={cn('text-sm', {
+                                      ['cursor-pointer']: !selected,
+                                    })}
+                                  >
+                                    <Trans
+                                      i18nKey={`billing:billingInterval.${interval}`}
+                                    />
+                                  </span>
+                                </label>
+                              );
+                            })}
+                          </div>
+                        </RadioGroup>
+                      </FormControl>
+
+                      <FormMessage />
+                    </FormItem>
+                  );
+                }}
+              />
+            </div>
+          </If>
+
+          <FormField
+            name={'planId'}
+            render={({ field }) => (
+              <FormItem className={'flex flex-col gap-4'}>
+                <FormLabel>
+                  <Trans i18nKey={'common:planPickerLabel'} />
+                </FormLabel>
+
+                <FormControl>
+                  <RadioGroup value={field.value} name={field.name}>
+                    {visibleProducts.map((product) => {
+                      const plan = product.plans.find((item) => {
+                        if (item.paymentType === 'one-time') {
+                          return true;
+                        }
+
+                        return item.interval === selectedInterval;
+                      });
+
+                      if (!plan || plan.custom) {
+                        return null;
+                      }
+
+                      const planId = plan.id;
+                      const selected = field.value === planId;
+
+                      const primaryLineItem = getPrimaryLineItem(
+                        props.config,
+                        planId,
+                      );
+
+                      if (!primaryLineItem) {
+                        throw new Error(`Base line item was not found`);
+                      }
+
+                      return (
+                        <RadioGroupItemLabel
+                          selected={selected}
+                          key={primaryLineItem.id}
+                        >
+                          <RadioGroupItem
+                            data-test-plan={plan.id}
+                            key={plan.id + selected}
+                            id={plan.id}
+                            value={plan.id}
+                            onClick={() => {
+                              if (selected) {
+                                return;
+                              }
+
+                              form.setValue('planId', planId, {
+                                shouldValidate: true,
+                              });
+
+                              form.setValue('productId', product.id, {
+                                shouldValidate: true,
+                              });
+                            }}
+                          />
+
+                          <div
+                            className={
+                              'flex w-full flex-col content-center gap-y-3 lg:flex-row lg:items-center lg:justify-between lg:space-y-0'
+                            }
+                          >
+                            <Label
+                              htmlFor={plan.id}
+                              className={
+                                'flex flex-col justify-center space-y-2'
+                              }
+                            >
+                              <div className={'flex items-center space-x-2.5'}>
+                                <span className="font-semibold">
+                                  <Trans
+                                    i18nKey={`billing:plans.${product.id}.name`}
+                                    defaults={product.name}
+                                  />
+                                </span>
+
+                                <If
+                                  condition={
+                                    plan.trialDays && props.canStartTrial
+                                  }
+                                >
+                                  <div>
+                                    <Badge
+                                      className={'px-1 py-0.5 text-xs'}
+                                      variant={'success'}
+                                    >
+                                      <Trans
+                                        i18nKey={`billing:trialPeriod`}
+                                        values={{
+                                          period: plan.trialDays,
+                                        }}
+                                      />
+                                    </Badge>
+                                  </div>
+                                </If>
+                              </div>
+
+                              <span className={'text-muted-foreground'}>
+                                <Trans
+                                  i18nKey={`billing:plans.${product.id}.description`}
+                                  defaults={product.description}
+                                />
+                              </span>
+                            </Label>
+
+                            <div
+                              className={
+                                'flex flex-col gap-y-3 lg:flex-row lg:items-center lg:space-x-4 lg:space-y-0 lg:text-right'
+                              }
+                            >
+                              <div>
+                                <Price key={plan.id}>
+                                  <PlanCostDisplay
+                                    primaryLineItem={primaryLineItem}
+                                    currencyCode={product.currency}
+                                    interval={selectedInterval}
+                                    alwaysDisplayMonthlyPrice={true}
+                                  />
+                                </Price>
+
+                                <div>
+                                  <span className={'text-muted-foreground'}>
+                                    <If
+                                      condition={
+                                        plan.paymentType === 'recurring'
+                                      }
+                                      fallback={
+                                        <Trans i18nKey={`billing:lifetime`} />
+                                      }
+                                    >
+                                      <Trans i18nKey={`billing:perMonth`} />
+                                    </If>
+                                  </span>
+                                </div>
+                              </div>
+                            </div>
+                          </div>
+                        </RadioGroupItemLabel>
+                      );
+                    })}
+                  </RadioGroup>
+                </FormControl>
+
+                <FormMessage />
+              </FormItem>
+            )}
+          />
+
+          <div>
+            <Button
+              data-test="checkout-submit-button"
+              disabled={props.pending ?? !form.formState.isValid}
+            >
+              {props.pending ? (
+                t('redirectingToPayment')
+              ) : (
+                <>
+                  <If
+                    condition={selectedPlan?.trialDays && props.canStartTrial}
+                    fallback={t(`proceedToPayment`)}
+                  >
+                    <span>{t(`startTrial`)}</span>
+                  </If>
+
+                  <ArrowRight className={'ml-2 h-4 w-4'} />
+                </>
+              )}
+            </Button>
+          </div>
+        </form>
+
+        {selectedPlan && selectedInterval && selectedProduct ? (
+          <PlanDetails
+            selectedInterval={selectedInterval}
+            selectedPlan={selectedPlan}
+            selectedProduct={selectedProduct}
+          />
+        ) : null}
+      </div>
+    </Form>
+  );
+}
+
+function PlanDetails({
+  selectedProduct,
+  selectedInterval,
+  selectedPlan,
+}: {
+  selectedProduct: {
+    id: string;
+    name: string;
+    description: string;
+    currency: string;
+    features: string[];
+  };
+
+  selectedInterval: string;
+
+  selectedPlan: {
+    lineItems: z.infer<typeof LineItemSchema>[];
+    paymentType: string;
+  };
+}) {
+  const isRecurring = selectedPlan.paymentType === 'recurring';
+
+  // trick to force animation on re-render
+  const key = Math.random();
+
+  return (
+    <div
+      key={key}
+      className={
+        'fade-in animate-in zoom-in-95 flex w-full flex-col space-y-4 py-2 lg:px-8'
+      }
+    >
+      <div className={'flex flex-col space-y-0.5'}>
+        <span className={'text-sm font-medium'}>
+          <b>
+            <Trans
+              i18nKey={`billing:plans.${selectedProduct.id}.name`}
+              defaults={selectedProduct.name}
+            />
+          </b>{' '}
+          <If condition={isRecurring}>
+            / <Trans i18nKey={`billing:billingInterval.${selectedInterval}`} />
+          </If>
+        </span>
+
+        <p>
+          <span className={'text-muted-foreground text-sm'}>
+            <Trans
+              i18nKey={`billing:plans.${selectedProduct.id}.description`}
+              defaults={selectedProduct.description}
+            />
+          </span>
+        </p>
+      </div>
+
+      <If condition={selectedPlan.lineItems.length > 0}>
+        <Separator />
+
+        <div className={'flex flex-col space-y-2'}>
+          <span className={'text-sm font-semibold'}>
+            <Trans i18nKey={'billing:detailsLabel'} />
+          </span>
+
+          <LineItemDetails
+            lineItems={selectedPlan.lineItems ?? []}
+            selectedInterval={isRecurring ? selectedInterval : undefined}
+            currency={selectedProduct.currency}
+          />
+        </div>
+      </If>
+
+      <Separator />
+
+      <div className={'flex flex-col space-y-2'}>
+        <span className={'text-sm font-semibold'}>
+          <Trans i18nKey={'billing:featuresLabel'} />
+        </span>
+
+        {selectedProduct.features.map((item) => {
+          return (
+            <div key={item} className={'flex items-center gap-x-2 text-sm'}>
+              <CheckCircle className={'h-4 text-green-500'} />
+
+              <span className={'text-secondary-foreground'}>
+                <Trans i18nKey={item} defaults={item} />
+              </span>
+            </div>
+          );
+        })}
+      </div>
+    </div>
+  );
+}
+
+function Price(props: React.PropsWithChildren) {
+  return (
+    <span
+      className={
+        'animate-in slide-in-from-left-4 fade-in text-xl font-semibold tracking-tight duration-500'
+      }
+    >
+      {props.children}
+    </span>
+  );
+}

packages/billing/gateway/src/components/pricing-table.tsx

@@ -0,0 +1,519 @@
+'use client';
+
+import { useState } from 'react';
+
+import Link from 'next/link';
+
+import { ArrowRight, CheckCircle } from 'lucide-react';
+import { useTranslation } from 'react-i18next';
+import { z } from 'zod';
+
+import {
+  BillingConfig,
+  type LineItemSchema,
+  getPlanIntervals,
+  getPrimaryLineItem,
+} from '@kit/billing';
+import { Badge } from '@kit/ui/badge';
+import { Button } from '@kit/ui/button';
+import { If } from '@kit/ui/if';
+import { Trans } from '@kit/ui/trans';
+import { cn } from '@kit/ui/utils';
+
+import { LineItemDetails } from './line-item-details';
+import { PlanCostDisplay } from './plan-cost-display';
+
+interface Paths {
+  signUp: string;
+  return: string;
+}
+
+type Interval = 'month' | 'year';
+
+export function PricingTable({
+  config,
+  paths,
+  CheckoutButtonRenderer,
+  redirectToCheckout = true,
+  displayPlanDetails = true,
+  alwaysDisplayMonthlyPrice = true,
+}: {
+  config: BillingConfig;
+  paths: Paths;
+  displayPlanDetails?: boolean;
+  alwaysDisplayMonthlyPrice?: boolean;
+  redirectToCheckout?: boolean;
+
+  CheckoutButtonRenderer?: React.ComponentType<{
+    planId: string;
+    productId: string;
+    highlighted?: boolean;
+  }>;
+}) {
+  const intervals = getPlanIntervals(config).filter(Boolean) as Interval[];
+  const [interval, setInterval] = useState(intervals[0]!);
+
+  // Always filter out hidden products
+  const visibleProducts = config.products.filter((product) => !product.hidden);
+
+  return (
+    <div className={'flex flex-col space-y-8 xl:space-y-12'}>
+      <div className={'flex justify-center'}>
+        {intervals.length > 1 ? (
+          <PlanIntervalSwitcher
+            intervals={intervals}
+            interval={interval}
+            setInterval={setInterval}
+          />
+        ) : null}
+      </div>
+
+      <div
+        className={
+          'flex flex-col items-start space-y-6 lg:space-y-0' +
+          ' justify-center lg:flex-row lg:space-x-4'
+        }
+      >
+        {visibleProducts.map((product) => {
+          const plan = product.plans.find((plan) => {
+            if (plan.paymentType === 'recurring') {
+              return plan.interval === interval;
+            }
+
+            return plan;
+          });
+
+          if (!plan) {
+            return null;
+          }
+
+          const primaryLineItem = getPrimaryLineItem(config, plan.id);
+
+          if (!plan.custom && !primaryLineItem) {
+            throw new Error(`Primary line item not found for plan ${plan.id}`);
+          }
+
+          return (
+            <PricingItem
+              selectable
+              key={plan.id}
+              plan={plan}
+              redirectToCheckout={redirectToCheckout}
+              primaryLineItem={primaryLineItem}
+              product={product}
+              paths={paths}
+              displayPlanDetails={displayPlanDetails}
+              alwaysDisplayMonthlyPrice={alwaysDisplayMonthlyPrice}
+              CheckoutButton={CheckoutButtonRenderer}
+            />
+          );
+        })}
+      </div>
+    </div>
+  );
+}
+
+function PricingItem(
+  props: React.PropsWithChildren<{
+    className?: string;
+    displayPlanDetails: boolean;
+
+    paths: Paths;
+
+    selectable: boolean;
+
+    primaryLineItem: z.infer<typeof LineItemSchema> | undefined;
+
+    redirectToCheckout?: boolean;
+    alwaysDisplayMonthlyPrice?: boolean;
+
+    plan: {
+      id: string;
+      lineItems: z.infer<typeof LineItemSchema>[];
+      interval?: Interval;
+      name?: string;
+      href?: string;
+      label?: string;
+      custom?: boolean;
+    };
+
+    CheckoutButton?: React.ComponentType<{
+      planId: string;
+      productId: string;
+      highlighted?: boolean;
+    }>;
+
+    product: {
+      id: string;
+      name: string;
+      currency: string;
+      description: string;
+      badge?: string;
+      highlighted?: boolean;
+      features: string[];
+    };
+  }>,
+) {
+  const highlighted = props.product.highlighted ?? false;
+  const lineItem = props.primaryLineItem!;
+  const isCustom = props.plan.custom ?? false;
+
+  // we exclude flat line items from the details since
+  // it doesn't need further explanation
+  const lineItemsToDisplay = props.plan.lineItems.filter((item) => {
+    return item.type !== 'flat';
+  });
+
+  const interval = props.plan.interval as Interval;
+
+  return (
+    <div
+      data-cy={'subscription-plan'}
+      className={cn(
+        props.className,
+        `s-full relative flex flex-1 grow flex-col items-stretch justify-between self-stretch rounded-lg border px-6 py-5 lg:w-4/12 xl:max-w-[20rem]`,
+        {
+          ['border-primary']: highlighted,
+          ['border-border']: !highlighted,
+        },
+      )}
+    >
+      <If condition={props.product.badge}>
+        <div className={'absolute -top-2.5 left-0 flex w-full justify-center'}>
+          <Badge
+            className={highlighted ? '' : 'bg-background'}
+            variant={highlighted ? 'default' : 'outline'}
+          >
+            <span>
+              <Trans
+                i18nKey={props.product.badge}
+                defaults={props.product.badge}
+              />
+            </span>
+          </Badge>
+        </div>
+      </If>
+
+      <div className={'flex flex-col gap-y-5'}>
+        <div className={'flex flex-col gap-y-1'}>
+          <div className={'flex items-center space-x-6'}>
+            <b
+              className={
+                'text-secondary-foreground font-heading text-xl font-medium tracking-tight'
+              }
+            >
+              <Trans
+                i18nKey={props.product.name}
+                defaults={props.product.name}
+              />
+            </b>
+          </div>
+        </div>
+
+        <div className={'mt-6 flex flex-col gap-y-1'}>
+          <Price
+            isMonthlyPrice={props.alwaysDisplayMonthlyPrice}
+            displayBillingPeriod={!props.plan.label}
+          >
+            <If
+              condition={!isCustom}
+              fallback={
+                <Trans i18nKey={props.plan.label} defaults={props.plan.label} />
+              }
+            >
+              <PlanCostDisplay
+                primaryLineItem={lineItem}
+                currencyCode={props.product.currency}
+                interval={interval}
+                alwaysDisplayMonthlyPrice={props.alwaysDisplayMonthlyPrice}
+              />
+            </If>
+          </Price>
+
+          <If condition={props.plan.name}>
+            <span
+              className={cn(
+                `animate-in slide-in-from-left-4 fade-in text-muted-foreground flex items-center gap-x-1 text-xs capitalize`,
+              )}
+            >
+              <span>
+                <If
+                  condition={props.plan.interval}
+                  fallback={<Trans i18nKey={'billing:lifetime'} />}
+                >
+                  {(interval) => (
+                    <Trans i18nKey={`billing:billingInterval.${interval}`} />
+                  )}
+                </If>
+              </span>
+
+              <If condition={lineItem && lineItem?.type !== 'flat'}>
+                <span>/</span>
+
+                <span
+                  className={cn(
+                    `animate-in slide-in-from-left-4 fade-in text-sm capitalize`,
+                  )}
+                >
+                  <If condition={lineItem?.type === 'per_seat'}>
+                    <Trans i18nKey={'billing:perTeamMember'} />
+                  </If>
+
+                  <If condition={lineItem?.unit}>
+                    <Trans
+                      i18nKey={'billing:perUnit'}
+                      values={{
+                        unit: lineItem?.unit,
+                      }}
+                    />
+                  </If>
+                </span>
+              </If>
+            </span>
+          </If>
+        </div>
+
+        <If condition={props.selectable}>
+          <If
+            condition={props.plan.id && props.CheckoutButton}
+            fallback={
+              <DefaultCheckoutButton
+                paths={props.paths}
+                product={props.product}
+                highlighted={highlighted}
+                plan={props.plan}
+                redirectToCheckout={props.redirectToCheckout}
+              />
+            }
+          >
+            {(CheckoutButton) => (
+              <CheckoutButton
+                highlighted={highlighted}
+                planId={props.plan.id}
+                productId={props.product.id}
+              />
+            )}
+          </If>
+        </If>
+
+        <span className={cn(`text-muted-foreground text-base tracking-tight`)}>
+          <Trans
+            i18nKey={props.product.description}
+            defaults={props.product.description}
+          />
+        </span>
+
+        <div className={'h-px w-full border border-dashed'} />
+
+        <div className={'flex flex-col'}>
+          <FeaturesList
+            highlighted={highlighted}
+            features={props.product.features}
+          />
+        </div>
+
+        <If condition={props.displayPlanDetails && lineItemsToDisplay.length}>
+          <div className={'h-px w-full border border-dashed'} />
+
+          <div className={'flex flex-col space-y-2'}>
+            <h6 className={'text-sm font-semibold'}>
+              <Trans i18nKey={'billing:detailsLabel'} />
+            </h6>
+
+            <LineItemDetails
+              selectedInterval={props.plan.interval}
+              currency={props.product.currency}
+              lineItems={lineItemsToDisplay}
+            />
+          </div>
+        </If>
+      </div>
+    </div>
+  );
+}
+
+function FeaturesList(
+  props: React.PropsWithChildren<{
+    features: string[];
+    highlighted: boolean;
+  }>,
+) {
+  return (
+    <ul className={'flex flex-col gap-1'}>
+      {props.features.map((feature) => {
+        return (
+          <ListItem highlighted={props.highlighted} key={feature}>
+            <Trans i18nKey={feature} defaults={feature} />
+          </ListItem>
+        );
+      })}
+    </ul>
+  );
+}
+
+function Price({
+  children,
+  isMonthlyPrice = true,
+  displayBillingPeriod = true,
+}: React.PropsWithChildren<{
+  isMonthlyPrice?: boolean;
+  displayBillingPeriod?: boolean;
+}>) {
+  return (
+    <div
+      className={`animate-in slide-in-from-left-4 fade-in flex items-end gap-1 duration-500`}
+    >
+      <span
+        className={
+          'font-heading flex items-center text-4xl font-medium tracking-tighter'
+        }
+      >
+        {children}
+      </span>
+
+      <If condition={isMonthlyPrice && displayBillingPeriod}>
+        <span className={'text-muted-foreground text-sm leading-loose'}>
+          <span>/</span>
+
+          <Trans i18nKey={'billing:perMonth'} />
+        </span>
+      </If>
+    </div>
+  );
+}
+
+function ListItem({
+  children,
+  highlighted,
+}: React.PropsWithChildren<{
+  highlighted: boolean;
+}>) {
+  return (
+    <li className={'flex items-center gap-x-2.5'}>
+      <CheckCircle
+        className={cn('h-4 min-h-4 w-4 min-w-4', {
+          'text-secondary-foreground': highlighted,
+          'text-muted-foreground': !highlighted,
+        })}
+      />
+
+      <span
+        className={cn('text-sm', {
+          'text-muted-foreground': !highlighted,
+          'text-secondary-foreground': highlighted,
+        })}
+      >
+        {children}
+      </span>
+    </li>
+  );
+}
+
+function PlanIntervalSwitcher(
+  props: React.PropsWithChildren<{
+    intervals: Interval[];
+    interval: Interval;
+    setInterval: (interval: Interval) => void;
+  }>,
+) {
+  return (
+    <div className={'flex gap-x-1 rounded-full border p-1.5'}>
+      {props.intervals.map((plan, index) => {
+        const selected = plan === props.interval;
+
+        const className = cn(
+          'animate-in fade-in !outline-hidden rounded-full transition-all focus:!ring-0',
+          {
+            'border-r-transparent': index === 0,
+            ['hover:text-primary text-muted-foreground']: !selected,
+            ['cursor-default font-semibold']: selected,
+            ['hover:bg-initial']: !selected,
+          },
+        );
+
+        return (
+          <Button
+            key={plan}
+            size={'sm'}
+            variant={selected ? 'default' : 'ghost'}
+            className={className}
+            onClick={() => props.setInterval(plan)}
+          >
+            <span className={'flex items-center'}>
+              <CheckCircle
+                className={cn('animate-in fade-in zoom-in-95 h-3.5', {
+                  hidden: !selected,
+                  'slide-in-from-left-4': index === 0,
+                  'slide-in-from-right-4': index === props.intervals.length - 1,
+                })}
+              />
+
+              <span className={'capitalize'}>
+                <Trans i18nKey={`common:billingInterval.${plan}`} />
+              </span>
+            </span>
+          </Button>
+        );
+      })}
+    </div>
+  );
+}
+
+function DefaultCheckoutButton(
+  props: React.PropsWithChildren<{
+    plan: {
+      id: string;
+      name?: string | undefined;
+      href?: string;
+      buttonLabel?: string;
+    };
+
+    product: {
+      name: string;
+    };
+
+    paths: Paths;
+    redirectToCheckout?: boolean;
+
+    highlighted?: boolean;
+  }>,
+) {
+  const { t } = useTranslation('billing');
+
+  const signUpPath = props.paths.signUp;
+
+  const searchParams = new URLSearchParams({
+    next: props.paths.return,
+    plan: props.plan.id,
+    redirectToCheckout: props.redirectToCheckout ? 'true' : 'false',
+  });
+
+  const linkHref =
+    props.plan.href ?? `${signUpPath}?${searchParams.toString()}`;
+
+  const label = props.plan.buttonLabel ?? 'common:getStartedWithPlan';
+
+  return (
+    <Link className={'w-full'} href={linkHref}>
+      <Button
+        size={'lg'}
+        className={'h-12 w-full rounded-lg'}
+        variant={props.highlighted ? 'default' : 'secondary'}
+      >
+        <span className={'text-base font-medium tracking-tight'}>
+          <Trans
+            i18nKey={label}
+            defaults={label}
+            values={{
+              plan: t(props.product.name, {
+                defaultValue: props.product.name,
+              }),
+            }}
+          />
+        </span>
+
+        <ArrowRight className={'ml-2 h-4'} />
+      </Button>
+    </Link>
+  );
+}

packages/billing/gateway/src/index.ts

@@ -0,0 +1,4 @@
+export * from './server/services/billing-gateway/billing-gateway.service';
+export * from './server/services/billing-gateway/billing-gateway-provider-factory';
+export * from './server/services/billing-event-handler/billing-event-handler-provider';
+export * from './server/services/billing-webhooks/billing-webhooks.service';

packages/billing/gateway/src/server/services/billing-event-handler/billing-event-handler-factory.service.ts

@@ -0,0 +1,48 @@
+import 'server-only';
+
+import { z } from 'zod';
+
+import {
+  type BillingProviderSchema,
+  BillingWebhookHandlerService,
+  type PlanTypeMap,
+} from '@kit/billing';
+import { createRegistry } from '@kit/shared/registry';
+
+/**
+ * @description Creates a registry for billing webhook handlers
+ * @param planTypesMap - A map of plan types as setup by the user in the billing config
+ * @returns The billing webhook handler registry
+ */
+export function createBillingEventHandlerFactoryService(
+  planTypesMap: PlanTypeMap,
+) {
+  // Create a registry for billing webhook handlers
+  const billingWebhookHandlerRegistry = createRegistry<
+    BillingWebhookHandlerService,
+    z.infer<typeof BillingProviderSchema>
+  >();
+
+  // Register the Stripe webhook handler
+  billingWebhookHandlerRegistry.register('stripe', async () => {
+    const { StripeWebhookHandlerService } = await import('@kit/stripe');
+
+    return new StripeWebhookHandlerService(planTypesMap);
+  });
+
+  // Register the Lemon Squeezy webhook handler
+  billingWebhookHandlerRegistry.register('lemon-squeezy', async () => {
+    const { LemonSqueezyWebhookHandlerService } = await import(
+      '@kit/lemon-squeezy'
+    );
+
+    return new LemonSqueezyWebhookHandlerService(planTypesMap);
+  });
+
+  // Register Paddle webhook handler (not implemented yet)
+  billingWebhookHandlerRegistry.register('paddle', () => {
+    throw new Error('Paddle is not supported yet');
+  });
+
+  return billingWebhookHandlerRegistry;
+}

packages/billing/gateway/src/server/services/billing-event-handler/billing-event-handler-provider.ts

@@ -0,0 +1,32 @@
+import 'server-only';
+
+import type { SupabaseClient } from '@supabase/supabase-js';
+
+import type { PlanTypeMap } from '@kit/billing';
+import { Database, Enums } from '@kit/supabase/database';
+
+import { createBillingEventHandlerFactoryService } from './billing-event-handler-factory.service';
+import { createBillingEventHandlerService } from './billing-event-handler.service';
+
+// a function that returns a Supabase client
+type ClientProvider = () => SupabaseClient<Database>;
+
+// the billing provider from the database
+type BillingProvider = Enums<'billing_provider'>;
+
+/**
+ * @name getBillingEventHandlerService
+ * @description This function retrieves the billing provider from the database and returns a
+ * new instance of the `BillingGatewayService` class. This class is used to interact with the server actions
+ * defined in the host application.
+ */
+export async function getBillingEventHandlerService(
+  clientProvider: ClientProvider,
+  provider: BillingProvider,
+  planTypesMap: PlanTypeMap,
+) {
+  const strategy =
+    await createBillingEventHandlerFactoryService(planTypesMap).get(provider);
+
+  return createBillingEventHandlerService(clientProvider, strategy);
+}

packages/billing/gateway/src/server/services/billing-event-handler/billing-event-handler.service.ts

@@ -0,0 +1,285 @@
+import 'server-only';
+
+import { SupabaseClient } from '@supabase/supabase-js';
+
+import { BillingWebhookHandlerService } from '@kit/billing';
+import {
+  UpsertOrderParams,
+  UpsertSubscriptionParams,
+} from '@kit/billing/types';
+import { getLogger } from '@kit/shared/logger';
+import { Database } from '@kit/supabase/database';
+
+/**
+ * @name CustomHandlersParams
+ * @description Allow consumers to provide custom handlers for the billing events
+ * that are triggered by the webhook events.
+ */
+interface CustomHandlersParams {
+  onSubscriptionDeleted: (subscriptionId: string) => Promise<unknown>;
+  onSubscriptionUpdated: (
+    subscription: UpsertSubscriptionParams,
+  ) => Promise<unknown>;
+  onCheckoutSessionCompleted: (
+    subscription: UpsertSubscriptionParams | UpsertOrderParams,
+    customerId: string,
+  ) => Promise<unknown>;
+  onPaymentSucceeded: (sessionId: string) => Promise<unknown>;
+  onPaymentFailed: (sessionId: string) => Promise<unknown>;
+  onInvoicePaid: (subscription: UpsertSubscriptionParams) => Promise<unknown>;
+  onEvent(event: unknown): Promise<unknown>;
+}
+
+/**
+ * @name createBillingEventHandlerService
+ * @description Create a new instance of the `BillingEventHandlerService` class
+ * @param clientProvider
+ * @param strategy
+ */
+export function createBillingEventHandlerService(
+  clientProvider: () => SupabaseClient<Database>,
+  strategy: BillingWebhookHandlerService,
+) {
+  return new BillingEventHandlerService(clientProvider, strategy);
+}
+
+/**
+ * @name BillingEventHandlerService
+ * @description This class is used to handle the webhook events from the billing provider
+ */
+class BillingEventHandlerService {
+  private readonly namespace = 'billing';
+
+  constructor(
+    private readonly clientProvider: () => SupabaseClient<Database>,
+    private readonly strategy: BillingWebhookHandlerService,
+  ) {}
+
+  /**
+   * @name handleWebhookEvent
+   * @description Handle the webhook event from the billing provider
+   * @param request
+   * @param params
+   */
+  async handleWebhookEvent(
+    request: Request,
+    params: Partial<CustomHandlersParams> = {},
+  ) {
+    const event = await this.strategy.verifyWebhookSignature(request);
+
+    if (!event) {
+      throw new Error('Invalid signature');
+    }
+
+    return this.strategy.handleWebhookEvent(event, {
+      onSubscriptionDeleted: async (subscriptionId: string) => {
+        const client = this.clientProvider();
+        const logger = await getLogger();
+
+        const ctx = {
+          namespace: this.namespace,
+          subscriptionId,
+        };
+
+        // Handle the subscription deleted event
+        // here we delete the subscription from the database
+        logger.info(ctx, 'Processing subscription deleted event...');
+
+        const { error } = await client
+          .from('subscriptions')
+          .delete()
+          .match({ id: subscriptionId });
+
+        if (error) {
+          logger.error(
+            {
+              error,
+              ...ctx,
+            },
+            `Failed to delete subscription`,
+          );
+
+          throw new Error('Failed to delete subscription');
+        }
+
+        if (params.onSubscriptionDeleted) {
+          await params.onSubscriptionDeleted(subscriptionId);
+        }
+
+        logger.info(ctx, 'Successfully deleted subscription');
+      },
+      onSubscriptionUpdated: async (subscription) => {
+        const client = this.clientProvider();
+        const logger = await getLogger();
+
+        const ctx = {
+          namespace: this.namespace,
+          subscriptionId: subscription.target_subscription_id,
+          provider: subscription.billing_provider,
+          accountId: subscription.target_account_id,
+          customerId: subscription.target_customer_id,
+        };
+
+        logger.info(ctx, 'Processing subscription updated event ...');
+
+        // Handle the subscription updated event
+        // here we update the subscription in the database
+        const { error } = await client.rpc('upsert_subscription', subscription);
+
+        if (error) {
+          logger.error(
+            {
+              error,
+              ...ctx,
+            },
+            'Failed to update subscription',
+          );
+
+          throw new Error('Failed to update subscription');
+        }
+
+        if (params.onSubscriptionUpdated) {
+          await params.onSubscriptionUpdated(subscription);
+        }
+
+        logger.info(ctx, 'Successfully updated subscription');
+      },
+      onCheckoutSessionCompleted: async (payload) => {
+        // Handle the checkout session completed event
+        // here we add the subscription to the database
+        const client = this.clientProvider();
+        const logger = await getLogger();
+
+        // Check if the payload contains an order_id
+        // if it does, we add an order, otherwise we add a subscription
+        if ('target_order_id' in payload) {
+          const ctx = {
+            namespace: this.namespace,
+            orderId: payload.target_order_id,
+            provider: payload.billing_provider,
+            accountId: payload.target_account_id,
+            customerId: payload.target_customer_id,
+          };
+
+          logger.info(ctx, 'Processing order completed event...');
+
+          const { error } = await client.rpc('upsert_order', payload);
+
+          if (error) {
+            logger.error({ ...ctx, error }, 'Failed to add order');
+
+            throw new Error('Failed to add order');
+          }
+
+          if (params.onCheckoutSessionCompleted) {
+            await params.onCheckoutSessionCompleted(
+              payload,
+              payload.target_customer_id,
+            );
+          }
+
+          logger.info(ctx, 'Successfully added order');
+        } else {
+          const ctx = {
+            namespace: this.namespace,
+            subscriptionId: payload.target_subscription_id,
+            provider: payload.billing_provider,
+            accountId: payload.target_account_id,
+            customerId: payload.target_customer_id,
+          };
+
+          logger.info(ctx, 'Processing checkout session completed event...');
+
+          const { error } = await client.rpc('upsert_subscription', payload);
+
+          // handle the error
+          if (error) {
+            logger.error({ ...ctx, error }, 'Failed to add subscription');
+
+            throw new Error('Failed to add subscription');
+          }
+
+          // allow consumers to provide custom handlers for the event
+          if (params.onCheckoutSessionCompleted) {
+            await params.onCheckoutSessionCompleted(
+              payload,
+              payload.target_customer_id,
+            );
+          }
+
+          // all good
+          logger.info(ctx, 'Successfully added subscription');
+        }
+      },
+      onPaymentSucceeded: async (sessionId: string) => {
+        const client = this.clientProvider();
+        const logger = await getLogger();
+
+        const ctx = {
+          namespace: this.namespace,
+          sessionId,
+        };
+
+        // Handle the payment succeeded event
+        // here we update the payment status in the database
+        logger.info(ctx, 'Processing payment succeeded event...');
+
+        const { error } = await client
+          .from('orders')
+          .update({ status: 'succeeded' })
+          .match({ id: sessionId });
+
+        // handle the error
+        if (error) {
+          logger.error({ error, ...ctx }, 'Failed to update payment status');
+
+          throw new Error('Failed to update payment status');
+        }
+
+        // allow consumers to provide custom handlers for the event
+        if (params.onPaymentSucceeded) {
+          await params.onPaymentSucceeded(sessionId);
+        }
+
+        logger.info(ctx, 'Successfully updated payment status');
+      },
+      onPaymentFailed: async (sessionId: string) => {
+        const client = this.clientProvider();
+        const logger = await getLogger();
+
+        const ctx = {
+          namespace: this.namespace,
+          sessionId,
+        };
+
+        // Handle the payment failed event
+        // here we update the payment status in the database
+        logger.info(ctx, 'Processing payment failed event');
+
+        const { error } = await client
+          .from('orders')
+          .update({ status: 'failed' })
+          .match({ id: sessionId });
+
+        if (error) {
+          logger.error({ error, ...ctx }, 'Failed to update payment status');
+
+          throw new Error('Failed to update payment status');
+        }
+
+        // allow consumers to provide custom handlers for the event
+        if (params.onPaymentFailed) {
+          await params.onPaymentFailed(sessionId);
+        }
+
+        logger.info(ctx, 'Successfully updated payment status');
+      },
+      onInvoicePaid: async (payload) => {
+        if (params.onInvoicePaid) {
+          return params.onInvoicePaid(payload);
+        }
+      },
+      onEvent: params.onEvent,
+    });
+  }
+}

packages/billing/gateway/src/server/services/billing-gateway/billing-gateway-provider-factory.ts

@@ -0,0 +1,33 @@
+import 'server-only';
+
+import { SupabaseClient } from '@supabase/supabase-js';
+
+import { Database } from '@kit/supabase/database';
+
+import { createBillingGatewayService } from './billing-gateway.service';
+
+/**
+ * @description This function retrieves the billing provider from the database and returns a
+ * new instance of the `BillingGatewayService` class. This class is used to interact with the server actions
+ * defined in the host application.
+ */
+export async function getBillingGatewayProvider(
+  client: SupabaseClient<Database>,
+) {
+  const provider = await getBillingProvider(client);
+
+  return createBillingGatewayService(provider);
+}
+
+async function getBillingProvider(client: SupabaseClient<Database>) {
+  const { data, error } = await client
+    .from('config')
+    .select('billing_provider')
+    .single();
+
+  if (error ?? !data.billing_provider) {
+    throw error;
+  }
+
+  return data.billing_provider;
+}

packages/billing/gateway/src/server/services/billing-gateway/billing-gateway-registry.ts

@@ -0,0 +1,34 @@
+import 'server-only';
+
+import { z } from 'zod';
+
+import {
+  type BillingProviderSchema,
+  BillingStrategyProviderService,
+} from '@kit/billing';
+import { createRegistry } from '@kit/shared/registry';
+
+// Create a registry for billing strategy providers
+export const billingStrategyRegistry = createRegistry<
+  BillingStrategyProviderService,
+  z.infer<typeof BillingProviderSchema>
+>();
+
+// Register the Stripe billing strategy
+billingStrategyRegistry.register('stripe', async () => {
+  const { StripeBillingStrategyService } = await import('@kit/stripe');
+  return new StripeBillingStrategyService();
+});
+
+// Register the Lemon Squeezy billing strategy
+billingStrategyRegistry.register('lemon-squeezy', async () => {
+  const { LemonSqueezyBillingStrategyService } = await import(
+    '@kit/lemon-squeezy'
+  );
+  return new LemonSqueezyBillingStrategyService();
+});
+
+// Register Paddle billing strategy (not implemented yet)
+billingStrategyRegistry.register('paddle', () => {
+  throw new Error('Paddle is not supported yet');
+});

packages/billing/gateway/src/server/services/billing-gateway/billing-gateway.service.ts

@@ -0,0 +1,143 @@
+import { z } from 'zod';
+
+import type { BillingProviderSchema } from '@kit/billing';
+import {
+  CancelSubscriptionParamsSchema,
+  CreateBillingCheckoutSchema,
+  CreateBillingPortalSessionSchema,
+  QueryBillingUsageSchema,
+  ReportBillingUsageSchema,
+  RetrieveCheckoutSessionSchema,
+  UpdateSubscriptionParamsSchema,
+} from '@kit/billing/schema';
+
+import { billingStrategyRegistry } from './billing-gateway-registry';
+
+export function createBillingGatewayService(
+  provider: z.infer<typeof BillingProviderSchema>,
+) {
+  return new BillingGatewayService(provider);
+}
+
+/**
+ * @description The billing gateway service to interact with the billing provider of choice (e.g. Stripe)
+ * @class BillingGatewayService
+ * @param {BillingProvider} provider - The billing provider to use
+ * @example
+ *
+ * const provider = 'stripe';
+ * const billingGatewayService = new BillingGatewayService(provider);
+ */
+class BillingGatewayService {
+  constructor(
+    private readonly provider: z.infer<typeof BillingProviderSchema>,
+  ) {}
+
+  /**
+   * Creates a checkout session for billing.
+   *
+   * @param {CreateBillingCheckoutSchema} params - The parameters for creating the checkout session.
+   *
+   */
+  async createCheckoutSession(
+    params: z.infer<typeof CreateBillingCheckoutSchema>,
+  ) {
+    const strategy = await this.getStrategy();
+    const payload = CreateBillingCheckoutSchema.parse(params);
+
+    return strategy.createCheckoutSession(payload);
+  }
+
+  /**
+   * Retrieves the checkout session from the specified provider.
+   *
+   * @param {RetrieveCheckoutSessionSchema} params - The parameters to retrieve the checkout session.
+   */
+  async retrieveCheckoutSession(
+    params: z.infer<typeof RetrieveCheckoutSessionSchema>,
+  ) {
+    const strategy = await this.getStrategy();
+    const payload = RetrieveCheckoutSessionSchema.parse(params);
+
+    return strategy.retrieveCheckoutSession(payload);
+  }
+
+  /**
+   * Creates a billing portal session for the specified parameters.
+   *
+   * @param {CreateBillingPortalSessionSchema} params - The parameters to create the billing portal session.
+   */
+  async createBillingPortalSession(
+    params: z.infer<typeof CreateBillingPortalSessionSchema>,
+  ) {
+    const strategy = await this.getStrategy();
+    const payload = CreateBillingPortalSessionSchema.parse(params);
+
+    return strategy.createBillingPortalSession(payload);
+  }
+
+  /**
+   * Cancels a subscription.
+   *
+   * @param {CancelSubscriptionParamsSchema} params - The parameters for cancelling the subscription.
+   */
+  async cancelSubscription(
+    params: z.infer<typeof CancelSubscriptionParamsSchema>,
+  ) {
+    const strategy = await this.getStrategy();
+    const payload = CancelSubscriptionParamsSchema.parse(params);
+
+    return strategy.cancelSubscription(payload);
+  }
+
+  /**
+   * Reports the usage of the billing.
+   * @description This is used to report the usage of the billing to the provider.
+   * @param params
+   */
+  async reportUsage(params: z.infer<typeof ReportBillingUsageSchema>) {
+    const strategy = await this.getStrategy();
+    const payload = ReportBillingUsageSchema.parse(params);
+
+    return strategy.reportUsage(payload);
+  }
+
+  /**
+   * @name queryUsage
+   * @description Queries the usage of the metered billing.
+   * @param params
+   */
+  async queryUsage(params: z.infer<typeof QueryBillingUsageSchema>) {
+    const strategy = await this.getStrategy();
+    const payload = QueryBillingUsageSchema.parse(params);
+
+    return strategy.queryUsage(payload);
+  }
+
+  /**
+   * Updates a subscription with the specified parameters.
+   * @param params
+   */
+  async updateSubscriptionItem(
+    params: z.infer<typeof UpdateSubscriptionParamsSchema>,
+  ) {
+    const strategy = await this.getStrategy();
+    const payload = UpdateSubscriptionParamsSchema.parse(params);
+
+    return strategy.updateSubscriptionItem(payload);
+  }
+
+  /**
+   * Retrieves a subscription from the provider.
+   * @param subscriptionId
+   */
+  async getSubscription(subscriptionId: string) {
+    const strategy = await this.getStrategy();
+
+    return strategy.getSubscription(subscriptionId);
+  }
+
+  private getStrategy() {
+    return billingStrategyRegistry.get(this.provider);
+  }
+}

packages/billing/gateway/src/server/services/billing-webhooks/billing-webhooks.service.ts

@@ -0,0 +1,37 @@
+import 'server-only';
+
+import { Tables } from '@kit/supabase/database';
+
+import { createBillingGatewayService } from '../billing-gateway/billing-gateway.service';
+
+type Subscription = Tables<'subscriptions'>;
+
+export function createBillingWebhooksService() {
+  return new BillingWebhooksService();
+}
+
+/**
+ * @name BillingWebhooksService
+ * @description Service for handling billing webhooks.
+ */
+class BillingWebhooksService {
+  /**
+   * @name handleSubscriptionDeletedWebhook
+   * @description Handles the webhook for when a subscription is deleted.
+   * @param subscription
+   */
+  async handleSubscriptionDeletedWebhook(subscription: Subscription) {
+    const gateway = createBillingGatewayService(subscription.billing_provider);
+
+    const subscriptionData = await gateway.getSubscription(subscription.id);
+    const isCanceled = subscriptionData.status === 'canceled';
+
+    if (isCanceled) {
+      return;
+    }
+
+    return gateway.cancelSubscription({
+      subscriptionId: subscription.id,
+    });
+  }
+}

packages/billing/gateway/tsconfig.json

@@ -0,0 +1,9 @@
+{
+  "extends": "@kit/tsconfig/base.json",
+  "compilerOptions": {
+    "tsBuildInfoFile": "node_modules/.cache/tsbuildinfo.json",
+    "types": ["react/experimental"]
+  },
+  "include": ["*.ts", "src"],
+  "exclude": ["node_modules"]
+}

packages/billing/lemon-squeezy/README.md

@@ -0,0 +1,5 @@
+# Billing / Lemon Squeezy - @kit/lemon-squeezy
+
+This package is responsible for handling all billing related operations using Lemon Squeezy.
+
+Please refer to the [documentation](https://makerkit.dev/docs/next-supabase-turbo/billing/lemon-squeezy).

packages/billing/lemon-squeezy/eslint.config.mjs

@@ -0,0 +1,3 @@
+import eslintConfigBase from '@kit/eslint-config/base.js';
+
+export default eslintConfigBase;

packages/billing/lemon-squeezy/node_modules/.bin/next

@@ -0,0 +1,17 @@
+#!/bin/sh
+basedir=$(dirname "$(echo "$0" | sed -e 's,\\,/,g')")
+
+case `uname` in
+    *CYGWIN*) basedir=`cygpath -w "$basedir"`;;
+esac
+
+if [ -z "$NODE_PATH" ]; then
+  export NODE_PATH="/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/dist/bin/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/dist/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/node_modules"
+else
+  export NODE_PATH="/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/dist/bin/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/dist/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules:/Users/devmcee/dev/mountbirch/MRB2B/node_modules/.pnpm/node_modules:$NODE_PATH"
+fi
+if [ -x "$basedir/node" ]; then
+  exec "$basedir/node"  "$basedir/../next/dist/bin/next" "$@"
+else
+  exec node  "$basedir/../next/dist/bin/next" "$@"
+fi

packages/billing/lemon-squeezy/node_modules/@kit/billing

@@ -0,0 +1 @@
+../../../core

packages/billing/lemon-squeezy/node_modules/@kit/eslint-config

@@ -0,0 +1 @@
+../../../../../tooling/eslint

packages/billing/lemon-squeezy/node_modules/@kit/prettier-config

@@ -0,0 +1 @@
+../../../../../tooling/prettier

packages/billing/lemon-squeezy/node_modules/@kit/shared

@@ -0,0 +1 @@
+../../../../shared

packages/billing/lemon-squeezy/node_modules/@kit/supabase

@@ -0,0 +1 @@
+../../../../supabase

packages/billing/lemon-squeezy/node_modules/@kit/tsconfig

@@ -0,0 +1 @@
+../../../../../tooling/typescript

packages/billing/lemon-squeezy/node_modules/@kit/ui

@@ -0,0 +1 @@
+../../../../ui

packages/billing/lemon-squeezy/node_modules/@lemonsqueezy/lemonsqueezy.js

@@ -0,0 +1 @@
+../../../../../node_modules/.pnpm/@lemonsqueezy+lemonsqueezy.js@4.0.0/node_modules/@lemonsqueezy/lemonsqueezy.js

packages/billing/lemon-squeezy/node_modules/@types/react

@@ -0,0 +1 @@
+../../../../../node_modules/.pnpm/@types+react@19.1.4/node_modules/@types/react

packages/billing/lemon-squeezy/node_modules/next

@@ -0,0 +1 @@
+../../../../node_modules/.pnpm/next@15.3.2_@babel+core@7.27.4_@opentelemetry+api@1.9.0_babel-plugin-react-compiler@19.1.0-rc_krzs4il3c2axvegn27goximifi/node_modules/next

packages/billing/lemon-squeezy/node_modules/react

@@ -0,0 +1 @@
+../../../../node_modules/.pnpm/react@19.1.0/node_modules/react

packages/billing/lemon-squeezy/node_modules/zod

@@ -0,0 +1 @@
+../../../../node_modules/.pnpm/zod@3.25.56/node_modules/zod

packages/billing/lemon-squeezy/package.json

@@ -0,0 +1,39 @@
+{
+  "name": "@kit/lemon-squeezy",
+  "private": true,
+  "version": "0.1.0",
+  "scripts": {
+    "clean": "git clean -xdf .turbo node_modules",
+    "format": "prettier --check \"**/*.{ts,tsx}\"",
+    "lint": "eslint .",
+    "typecheck": "tsc --noEmit"
+  },
+  "prettier": "@kit/prettier-config",
+  "exports": {
+    ".": "./src/index.ts",
+    "./components": "./src/components/index.ts"
+  },
+  "dependencies": {
+    "@lemonsqueezy/lemonsqueezy.js": "4.0.0"
+  },
+  "devDependencies": {
+    "@kit/billing": "workspace:*",
+    "@kit/eslint-config": "workspace:*",
+    "@kit/prettier-config": "workspace:*",
+    "@kit/shared": "workspace:*",
+    "@kit/supabase": "workspace:*",
+    "@kit/tsconfig": "workspace:*",
+    "@kit/ui": "workspace:*",
+    "@types/react": "19.1.4",
+    "next": "15.3.2",
+    "react": "19.1.0",
+    "zod": "^3.24.4"
+  },
+  "typesVersions": {
+    "*": {
+      "*": [
+        "src/*"
+      ]
+    }
+  }
+}

packages/billing/lemon-squeezy/src/components/index.ts

@@ -0,0 +1 @@
+export * from './lemon-squeezy-embedded-checkout';

packages/billing/lemon-squeezy/src/components/lemon-squeezy-embedded-checkout.tsx

@@ -0,0 +1,68 @@
+'use client';
+
+import { useEffect } from 'react';
+
+interface LemonSqueezyWindow extends Window {
+  createLemonSqueezy: () => void;
+  LemonSqueezy: {
+    Setup: (options: {
+      eventHandler: (event: { event: string } | string) => void;
+    }) => void;
+    Refresh: () => void;
+    Url: {
+      Open: (url: string) => void;
+      Close: () => void;
+    };
+  };
+}
+
+export function LemonSqueezyEmbeddedCheckout(props: {
+  checkoutToken: string;
+  onClose?: () => void;
+}) {
+  useLoadScript(props.checkoutToken, props.onClose);
+
+  return null;
+}
+
+function useLoadScript(
+  checkoutToken: string,
+  onClose: (() => void) | undefined,
+) {
+  useEffect(() => {
+    const script = document.createElement('script');
+
+    script.src = 'https://app.lemonsqueezy.com/js/lemon.js';
+
+    script.onload = () => {
+      const win = window as unknown as LemonSqueezyWindow;
+
+      win.createLemonSqueezy();
+      win.LemonSqueezy.Url.Open(checkoutToken);
+
+      if (onClose) {
+        win.LemonSqueezy.Setup({
+          eventHandler: (event) => {
+            if (typeof event === 'string') {
+              if (event === 'close') {
+                onClose();
+              }
+
+              return;
+            }
+
+            if (event.event === 'PaymentMethodUpdate.Closed') {
+              onClose();
+            }
+          },
+        });
+      }
+    };
+
+    document.body.appendChild(script);
+
+    return () => {
+      document.body.removeChild(script);
+    };
+  }, [checkoutToken, onClose]);
+}