feat(cli): add polar as better-auth plugin

apps/cli/src/constants.ts

@@ -13,6 +13,7 @@ export const DEFAULT_CONFIG_BASE = {
 	database: "sqlite",
 	orm: "drizzle",
 	auth: "better-auth",
+	payments: "none",
 	addons: ["turborepo"],
 	examples: [],
 	git: true,
@@ -39,8 +40,8 @@ export function getDefaultConfig() {
 export const DEFAULT_CONFIG = getDefaultConfig();
 
 export const dependencyVersionMap = {
-	"better-auth": "^1.3.9",
-	"@better-auth/expo": "^1.3.9",
+	"better-auth": "^1.3.10",
+	"@better-auth/expo": "^1.3.10",
 
 	"@clerk/nextjs": "^6.31.5",
 	"@clerk/clerk-react": "^5.45.0",
@@ -155,6 +156,9 @@ export const dependencyVersionMap = {
 	nitropack: "^2.12.4",
 
 	dotenv: "^17.2.1",
+
+	"@polar-sh/better-auth": "^1.1.3",
+	"@polar-sh/sdk": "^0.34.16",
 } as const;
 
 export type AvailableDependencies = keyof typeof dependencyVersionMap;

apps/cli/src/helpers/core/add-addons.ts

@@ -2,8 +2,8 @@ import path from "node:path";
 import { log } from "@clack/prompts";
 import pc from "picocolors";
 import type { AddInput, Addons, ProjectConfig } from "../../types";
-import { validateAddonCompatibility } from "../../utils/addon-compatibility";
 import { updateBtsConfig } from "../../utils/bts-config";
+import { validateAddonCompatibility } from "../../utils/compatibility-rules";
 import { exitWithError } from "../../utils/errors";
 import { setupAddons } from "../addons/addons-setup";
 import {
@@ -45,6 +45,7 @@ export async function addAddonsToProject(
 			addons: input.addons,
 			examples: detectedConfig.examples || [],
 			auth: detectedConfig.auth || "none",
+			payments: detectedConfig.payments || "none",
 			git: false,
 			packageManager:
 				input.packageManager || detectedConfig.packageManager || "npm",

apps/cli/src/helpers/core/add-deployment.ts

@@ -69,6 +69,7 @@ export async function addDeploymentToProject(
 			addons: detectedConfig.addons || [],
 			examples: detectedConfig.examples || [],
 			auth: detectedConfig.auth || "none",
+			payments: detectedConfig.payments || "none",
 			git: false,
 			packageManager:
 				input.packageManager || detectedConfig.packageManager || "npm",

apps/cli/src/helpers/core/command-handlers.ts

@@ -103,6 +103,7 @@ export async function createProjectHandler(
 				addons: [],
 				examples: [],
 				auth: "none",
+				payments: "none",
 				git: false,
 				packageManager: "npm",
 				install: false,
@@ -272,6 +273,7 @@ export async function addAddonsHandler(input: AddInput) {
 			const addonsPrompt = await getAddonsToAdd(
 				detectedConfig.frontend || [],
 				detectedConfig.addons || [],
+				detectedConfig.auth,
 			);
 
 			if (addonsPrompt.length > 0) {

apps/cli/src/helpers/core/create-project.ts

@@ -17,6 +17,7 @@ import { createReadme } from "./create-readme";
 import { setupEnvironmentVariables } from "./env-setup";
 import { initializeGit } from "./git";
 import { installDependencies } from "./install-dependencies";
+import { setupPayments } from "./payments-setup";
 import { displayPostInstallInstructions } from "./post-installation";
 import { updatePackageConfigurations } from "./project-config";
 import {
@@ -30,6 +31,7 @@ import {
 	setupDockerComposeTemplates,
 	setupExamplesTemplate,
 	setupFrontendTemplates,
+	setupPaymentsTemplate,
 } from "./template-manager";
 
 export async function createProject(
@@ -50,6 +52,9 @@ export async function createProject(
 			await setupDockerComposeTemplates(projectDir, options);
 		}
 		await setupAuthTemplate(projectDir, options);
+		if (options.payments && options.payments !== "none") {
+			await setupPaymentsTemplate(projectDir, options);
+		}
 		if (options.examples.length > 0 && options.examples[0] !== "none") {
 			await setupExamplesTemplate(projectDir, options);
 		}
@@ -76,6 +81,10 @@ export async function createProject(
 			await setupAuth(options);
 		}
 
+		if (options.payments && options.payments !== "none") {
+			await setupPayments(options);
+		}
+
 		await handleExtras(projectDir, options);
 
 		await setupEnvironmentVariables(options);

apps/cli/src/helpers/core/detect-project-config.ts

@@ -17,6 +17,7 @@ export async function detectProjectConfig(projectDir: string) {
 				addons: btsConfig.addons,
 				examples: btsConfig.examples,
 				auth: btsConfig.auth,
+				payments: btsConfig.payments,
 				packageManager: btsConfig.packageManager,
 				dbSetup: btsConfig.dbSetup,
 				api: btsConfig.api,

apps/cli/src/helpers/core/env-setup.ts

@@ -280,6 +280,16 @@ export async function setupEnvironmentVariables(config: ProjectConfig) {
 			value: "",
 			condition: examples?.includes("ai") || false,
 		},
+		{
+			key: "POLAR_ACCESS_TOKEN",
+			value: "",
+			condition: config.payments === "polar",
+		},
+		{
+			key: "POLAR_SUCCESS_URL",
+			value: `${corsOrigin}/success?checkout_id={CHECKOUT_ID}`,
+			condition: config.payments === "polar",
+		},
 	];
 
 	await addEnvVariablesToFile(envPath, serverVars);

apps/cli/src/helpers/core/payments-setup.ts

@@ -0,0 +1,50 @@
+import path from "node:path";
+import fs from "fs-extra";
+import type { ProjectConfig } from "../../types";
+import { addPackageDependency } from "../../utils/add-package-deps";
+
+export async function setupPayments(config: ProjectConfig) {
+	const { payments, projectDir, frontend } = config;
+
+	if (!payments || payments === "none") {
+		return;
+	}
+
+	const serverDir = path.join(projectDir, "apps/server");
+	const clientDir = path.join(projectDir, "apps/web");
+
+	const serverDirExists = await fs.pathExists(serverDir);
+	const clientDirExists = await fs.pathExists(clientDir);
+
+	if (!serverDirExists) {
+		return;
+	}
+
+	if (payments === "polar") {
+		await addPackageDependency({
+			dependencies: ["@polar-sh/better-auth", "@polar-sh/sdk"],
+			projectDir: serverDir,
+		});
+
+		if (clientDirExists) {
+			const hasWebFrontend = frontend.some((f) =>
+				[
+					"react-router",
+					"tanstack-router",
+					"tanstack-start",
+					"next",
+					"nuxt",
+					"svelte",
+					"solid",
+				].includes(f),
+			);
+
+			if (hasWebFrontend) {
+				await addPackageDependency({
+					dependencies: ["@polar-sh/better-auth"],
+					projectDir: clientDir,
+				});
+			}
+		}
+	}
+}

apps/cli/src/helpers/core/post-installation.ts

@@ -72,6 +72,10 @@ export async function displayPostInstallInstructions(
 		: "";
 	const clerkInstructions =
 		isConvex && config.auth === "clerk" ? getClerkInstructions() : "";
+	const polarInstructions =
+		config.payments === "polar" && config.auth === "better-auth"
+			? getPolarInstructions()
+			: "";
 	const wranglerDeployInstructions = getWranglerDeployInstructions(
 		runCmd,
 		webDeploy,
@@ -188,6 +192,7 @@ export async function displayPostInstallInstructions(
 		output += `\n${alchemyDeployInstructions.trim()}\n`;
 	if (starlightInstructions) output += `\n${starlightInstructions.trim()}\n`;
 	if (clerkInstructions) output += `\n${clerkInstructions.trim()}\n`;
+	if (polarInstructions) output += `\n${polarInstructions.trim()}\n`;
 
 	if (noOrmWarning) output += `\n${noOrmWarning.trim()}\n`;
 	if (bunWebNativeWarning) output += `\n${bunWebNativeWarning.trim()}\n`;
@@ -447,6 +452,10 @@ function getClerkInstructions() {
 	return `${pc.bold("Clerk Authentication Setup:")}\n${pc.cyan("•")} Follow the guide: ${pc.underline("https://docs.convex.dev/auth/clerk")}\n${pc.cyan("•")} Set CLERK_JWT_ISSUER_DOMAIN in Convex Dashboard\n${pc.cyan("•")} Set CLERK_PUBLISHABLE_KEY in apps/*/.env`;
 }
 
+function getPolarInstructions() {
+	return `${pc.bold("Polar Payments Setup:")}\n${pc.cyan("•")} Get access token & product ID from ${pc.underline("https://sandbox.polar.sh/")}\n${pc.cyan("•")} Set POLAR_ACCESS_TOKEN in apps/server/.env`;
+}
+
 function getAlchemyDeployInstructions(
 	runCmd?: string,
 	webDeploy?: string,

apps/cli/src/helpers/core/template-manager.ts

@@ -607,6 +607,102 @@ export async function setupAuthTemplate(
 	}
 }
 
+export async function setupPaymentsTemplate(
+	projectDir: string,
+	context: ProjectConfig,
+) {
+	if (!context.payments || context.payments === "none") return;
+
+	const serverAppDir = path.join(projectDir, "apps/server");
+	const webAppDir = path.join(projectDir, "apps/web");
+
+	const serverAppDirExists = await fs.pathExists(serverAppDir);
+	const webAppDirExists = await fs.pathExists(webAppDir);
+
+	if (serverAppDirExists && context.backend !== "convex") {
+		const paymentsServerSrc = path.join(
+			PKG_ROOT,
+			`templates/payments/${context.payments}/server/base`,
+		);
+		if (await fs.pathExists(paymentsServerSrc)) {
+			await processAndCopyFiles(
+				"**/*",
+				paymentsServerSrc,
+				serverAppDir,
+				context,
+			);
+		}
+	}
+
+	const hasReactWeb = context.frontend.some((f) =>
+		["tanstack-router", "react-router", "tanstack-start", "next"].includes(f),
+	);
+	const hasNuxtWeb = context.frontend.includes("nuxt");
+	const hasSvelteWeb = context.frontend.includes("svelte");
+	const hasSolidWeb = context.frontend.includes("solid");
+
+	if (
+		webAppDirExists &&
+		(hasReactWeb || hasNuxtWeb || hasSvelteWeb || hasSolidWeb)
+	) {
+		if (hasReactWeb) {
+			const reactFramework = context.frontend.find((f) =>
+				["tanstack-router", "react-router", "tanstack-start", "next"].includes(
+					f,
+				),
+			);
+			if (reactFramework) {
+				const paymentsWebSrc = path.join(
+					PKG_ROOT,
+					`templates/payments/${context.payments}/web/react/${reactFramework}`,
+				);
+				if (await fs.pathExists(paymentsWebSrc)) {
+					await processAndCopyFiles("**/*", paymentsWebSrc, webAppDir, context);
+				}
+			}
+		} else if (hasNuxtWeb) {
+			const paymentsWebNuxtSrc = path.join(
+				PKG_ROOT,
+				`templates/payments/${context.payments}/web/nuxt`,
+			);
+			if (await fs.pathExists(paymentsWebNuxtSrc)) {
+				await processAndCopyFiles(
+					"**/*",
+					paymentsWebNuxtSrc,
+					webAppDir,
+					context,
+				);
+			}
+		} else if (hasSvelteWeb) {
+			const paymentsWebSvelteSrc = path.join(
+				PKG_ROOT,
+				`templates/payments/${context.payments}/web/svelte`,
+			);
+			if (await fs.pathExists(paymentsWebSvelteSrc)) {
+				await processAndCopyFiles(
+					"**/*",
+					paymentsWebSvelteSrc,
+					webAppDir,
+					context,
+				);
+			}
+		} else if (hasSolidWeb) {
+			const paymentsWebSolidSrc = path.join(
+				PKG_ROOT,
+				`templates/payments/${context.payments}/web/solid`,
+			);
+			if (await fs.pathExists(paymentsWebSolidSrc)) {
+				await processAndCopyFiles(
+					"**/*",
+					paymentsWebSolidSrc,
+					webAppDir,
+					context,
+				);
+			}
+		}
+	}
+}
+
 export async function setupAddonsTemplate(
 	projectDir: string,
 	context: ProjectConfig,

apps/cli/src/index.ts

@@ -32,6 +32,7 @@ import {
 	ORMSchema,
 	type PackageManager,
 	PackageManagerSchema,
+	PaymentsSchema,
 	type ProjectConfig,
 	ProjectNameSchema,
 	type Runtime,
@@ -80,6 +81,7 @@ export const router = t.router({
 					database: DatabaseSchema.optional(),
 					orm: ORMSchema.optional(),
 					auth: AuthSchema.optional(),
+					payments: PaymentsSchema.optional(),
 					frontend: z.array(FrontendSchema).optional(),
 					addons: z.array(AddonsSchema).optional(),
 					examples: z.array(ExamplesSchema).optional(),

apps/cli/src/prompts/addons.ts

@@ -1,10 +1,10 @@
 import { groupMultiselect, isCancel } from "@clack/prompts";
 import { DEFAULT_CONFIG } from "../constants";
-import { type Addons, AddonsSchema, type Frontend } from "../types";
+import { type Addons, AddonsSchema, type Auth, type Frontend } from "../types";
 import {
 	getCompatibleAddons,
 	validateAddonCompatibility,
-} from "../utils/addon-compatibility";
+} from "../utils/compatibility-rules";
 import { exitCancelled } from "../utils/errors";
 
 type AddonOption = {
@@ -75,6 +75,7 @@ const ADDON_GROUPS = {
 export async function getAddonsChoice(
 	addons?: Addons[],
 	frontends?: Frontend[],
+	auth?: Auth,
 ) {
 	if (addons !== undefined) return addons;
 
@@ -88,7 +89,11 @@ export async function getAddonsChoice(
 	const frontendsArray = frontends || [];
 
 	for (const addon of allAddons) {
-		const { isCompatible } = validateAddonCompatibility(addon, frontendsArray);
+		const { isCompatible } = validateAddonCompatibility(
+			addon,
+			frontendsArray,
+			auth,
+		);
 		if (!isCompatible) continue;
 
 		const { label, hint } = getAddonDisplay(addon);
@@ -131,6 +136,7 @@ export async function getAddonsChoice(
 export async function getAddonsToAdd(
 	frontend: Frontend[],
 	existingAddons: Addons[] = [],
+	auth?: Auth,
 ) {
 	const groupedOptions: Record<string, AddonOption[]> = {
 		Documentation: [],
@@ -144,6 +150,7 @@ export async function getAddonsToAdd(
 		AddonsSchema.options.filter((addon) => addon !== "none"),
 		frontendArray,
 		existingAddons,
+		auth,
 	);
 
 	for (const addon of compatibleAddons) {