Lemon Squeezy Next.js Demo app

This Next.js demo app can be used as a base for building subscription-based SaaS apps.

Just clone this repo and build your app alongside the ready-made auth and billing!

• Lemon Squeezy for billing
• NextAuth.js for auth
• Prisma ORM
• Tailwind CSS for styling
• Resend for auth emails

Customer Portal vs Full billing section

This demo app comes with two versions of Lemon Squeezy billing.

1. The first option uses Lemon Squeezy's Customer Portal for managing subscriptions. It shows a "Manage subscription" button, which links out to the no-code Customer Portal where customers can manage their subscriptions, billing methods and view invoices.
   This option uses the PortalSubscriptionComponent component in billing/page.jsx.

2. The second option is a more native billing section inside the app, with options for pausing, cancelling, updating plans and updating payment method. This option is more seamless inside your application and uses the Lemon Squeezy SDK to make changes to subscriptions.
   This option uses the SubscriptionComponent component in billing/page.jsx.

Note that both options require webhooks so that the underlying subscription data in the application is always up-to-date. A way to ingest webhooks is included in the app.

How to set up a test version of the app

First, fork this repo and set up a project locally on your computer.

Next, you need a Lemon Squeezy account and store. If you don't have one already, sign up at app.lemonsqueezy.com/register.

Once you have created a store, make sure you're in Test mode, then go to Settings > API and create a new API key. Copy the key and paste it into .env.example file where it says LEMONSQUEEZY_API_KEY=.

You will also need the store ID from Lemon Squeezy for LEMONSQUEEZY_STORE_ID, which you can find in the list at Settings > Stores.

There are also a few other environment variables, which are all listed in .env.example:

• DATABASE_URL
• RESEND_API_KEY
• EMAIL_FROM_DEFAULT - The email address you send emails from
• NEXT_PUBLIC_EMAIL_FROM_DEFAULT - Same as EMAIL_FROM_DEFAULT. Read about browser variables
• NEXT_PUBLIC_ROOT_DOMAIN - The root domain of your site eg localhost:3000 or mydomain.com. Read about browser variables
• NEXTAUTH_URL - The URL of your site eg http://localhost:3000 or https://mydomain.com. Read more
• NEXTAUTH_SECRET - A secret used for auth. Read more

When you're done, rename the file .env so your app can read it.

Now, to get the code working on your computer or server, run npm install and then npm run dev to get the local server running.

Your site will load at http://localhost:3000.

How to set up webhooks

This is a required step.

For your app to receive data from Lemon Squeezy, you need to set up webhooks in your Lemon Squeezy store at Settings > Webhooks.

When you create a webhook, you should check at least these two events:

• subscription_created
• subscription_updated

This app demo only processes these two events, but they are enough to get a billing system in place. You could, for example, extend the app to handle successful payment events to list invoices in your billing system (by subscribing to subscription_payment_success).

The webhook endpoint in your app is /billing/webhook.

In the webhook form you need to add a signing secret. Add the same value you use in the form in the LEMONSQUEEZY_WEBHOOK_SECRET environment variable.

How to work with webhooks locally

Your local app will need to be able to receive webhook events, which means creating a web-accessible URL for your development project. This is not available when running your site on its local server without some sort of tunnel.

An easy way to set one up is using a service like ngrok or an app like LocalCan.

Once you are provided a URL by these services, simply add use that in your webhook settings form (make sure you add the path /billing/webhook to the end of the tunnel URL).

How to go live

There are a few things to update in your code to go live.

You need to switch out of live mode in your Lemon Squeezy store and add a new live mode API key. Add this API key as an environment variable in your live server, using the same name LEMONSQUEEZY_API_KEY. Your store ID remains the same in both test and live mode, so add that to your server environment variables, as you did for your development site.

You also need to create a new webhook in your live store. Make sure you add the signing secret into the LEMONSQUEEZY_WEBHOOK_SECRET variable on your server.