ssk · smisco subscription kit

Stripe subscriptions,
as a drop-in library.

A PHP library that wraps Stripe's whole subscription lifecycle — Checkout, Customer Portal, webhooks, access gating, admin operations — behind interfaces you implement. Your app supplies the database; the kit owns the Stripe logic.

Get started Read the docs

PHP 8.1+ stripe-php ^17 host-agnostic in production

// wire it up once, at boot
$stripe   = new StripeClient($secret, '2025-08-27');
$skus     = new SkuConfig([/* code => price */]);

// your DB lives behind these
$users    = new MyUserStore($db);
$subs     = new MySubscriptionStore($db);
$events   = new MyEventIdempotencyStore($db);

$checkout = new CheckoutService($stripe, $skus, $users);
$gate     = new AccessGate();
$webhook  = new WebhookReceiver($secret, $stripe, $skus,
                               $events, $subs, $users);

the shape

Three layers, one seam.

Pure decision logic at the core, the Stripe SDK confined to a handful of service classes, and persistence pushed out to interfaces your app implements.

Pure logic

Value objects and decisions with no Stripe calls and no database — access gating, expiration banners, SKU config, subscription state.

Stripe services

The only code that touches the Stripe SDK: CheckoutService, PortalService, WebhookReceiver, AdminActions.

Host interfaces

Persistence is yours. Implement the subscription, user, and event-idempotency stores against whatever database you run — MySQL, Postgres, SQLite.

what it handles

The whole lifecycle.

Checkout through cancellation, with the webhook receiver keeping your local state in sync — signature verification and event de-duplication included.

Checkout sessions Customer Portal Webhook receiver AccessGate decisions Expiration banners Admin sync / cancel / override one-off SKUs audit logging

install

A Composer VCS repository.

Not on Packagist. Add the kit's public GitHub repository as a Composer VCS repository, require it, and install — no local checkout needed.

Add the VCS repository and require the package in your app's composer.json:

{
  "repositories": [
    { "type": "vcs", "url": "https://github.com/grimblefritz/smisco-subscription-kit.git" }
  ],
  "require": { "smisco/subscription-kit": "^0.4" }
}

Releases are SemVer-tagged (v0.4.0, …) for Composer; pin the constraint as you would any dependency.

Install:
```
composer update smisco/subscription-kit
```
Local development (optional) — editing the kit alongside your app? Clone it as a sibling and use a path repository instead, so edits reflect without re-tagging:
```
{
  "repositories": [
    { "type": "path", "url": "../smisco-subscription-kit/public" }
  ],
  "require": { "smisco/subscription-kit": "@dev" }
}
```