Freemius Checkout

Freemius Checkout

Render pricing and open the Freemius Checkout overlay from a React frontend so a user can buy any modality — a recurring subscription or a one-off / top-up (credit) purchase — and have the result synced server-side.

Source: React Starter Kit Checkout components https://freemius.com/help/documentation/saas-sdk/react-starter/components/#checkout-components

Framework note. The examples in this Skill are Vite/Hono-flavored, but nothing here requires that stack: the server side (owned by freemius-core) works with any framework supporting Web-Standard Request/Response routing, and the React Starter Kit components target React 19+ with shadcn UI + Tailwind — install them via npx shadcn@latest add https://shadcn.freemius.com/all.json. If the app doesn't use shadcn/React, download the Starter Kit and use it as a reference to implement the same UI in the app's own framework. Prefer reusing the application's existing components (buttons, inputs, cards, dialogs) over re-creating primitives — port the Starter Kit's structure and behaviour onto the app's own design system rather than introducing new primitives.

Sandbox. Build and validate in sandbox mode — a checkout mode that accepts test credit cards (not a discount; no coupon is needed or involved). It is wired to the dedicated FREEMIUS_SANDBOX env var (never NODE_ENV) and owned by freemius-core — the server-created checkout already carries the sandbox flag; this Skill inherits it.

Golden rules (do not violate)

1. The overlay is the only thing that runs in the browser. It is primed with a server-created serialized checkout (checkout.serialize() from freemius-core). The secretKey/apiKey never reach the client.
2. The browser never trusts itself. A successful overlay purchase fires a callback that POSTs the payload to your backend, which re-fetches the authoritative purchase from Freemius and upserts the entitlement. The paywall is enforced server-side (HTTP 402); the UI gate is only UX.
   • ⛔️ The overlay sync and the hosted redirect are TWO SEPARATE endpoints with DIFFERENT payload contracts — never merge them. The overlay purchaseCompleted callback POSTs a JSON body to a dedicated POST /api/purchase; that handler reads the license_id out of the overlay payload and calls syncEntitlementByLicenseId(licenseId). The hosted return is a separate GET /api/checkout/redirect that runs freemius.checkout.processRedirect(url, PUBLIC_URL) on the signed query string (see freemius-core → purchase-processing). Do NOT route the overlay POST through freemius.checkout.request.createProcessor(...) / processRedirect(...), and do NOT point syncEndpoint at /api/checkout/redirect?action=process_purchase. Those SDK paths expect a signed redirect / license_id in a shape the overlay payload does not provide — the POST then returns 400 "License ID is required in the request body", the frontend .catch() swallows it, and user_fs_entitlement stays empty for every user while the UI looks fine. (createProcessor belongs to the customer-portal headless endpoint, not to overlay purchase sync — don't borrow it here.)
3. Pricing data comes from one server endpoint. The frontend fetches plans + prices + per-plan checkout context from your backend (GET /api/checkout/pricing); it never calls the Freemius API directly.
4. Cover every modality. Subscriptions use a billing-cycle toggle (monthly/annual); one-off/top-up plans open the overlay with billing_cycle: 'lifetime'. Render both — don't hardcode the demo's subscription-only path.
5. Never ask the maker to restate the subscription model. The pricing tables auto-fetch plans + prices from GET /api/checkout/pricing, which is sourced from the Freemius Dashboard. The Dashboard is the single source of truth for plans/pricing — detect the modalities from that data (a lifetime-only plan → Topup; monthly/annual plans → Subscribe); don't hard-specify them in a build prompt or intake question.
6. The app owns the post-purchase confirmation UX. Open the overlay with show_confirmation_dialog: false (skip Freemius' confirmation modal) and show an in-app success state instead — see In-app success message. In the same onPurchase handler, hide the paywall and clear any stale gate error/result from the gated action's 402, then re-check entitlement — otherwise a "need subscription"/"upgrade" message lingers on the gated surface until reload.
7. Purchase surfaces are entitlement-aware. Never show a plain Subscribe button to an already-subscribed user (a plain subscribe checkout creates a second parallel subscription — double-billing); their path is the server-built license-upgrade checkout (license fetch + setLicenseUpgradeByKey — see freemius-customer-portal; not checkout.create({ licenseId }), which 500s for renewing licenses). Hide the credits top-up for active-unlimited subscribers; mark the owned plan; note or hide Lifetime for subscribers. See references/pricing-tables.md → "Entitlement-aware rendering".

The components

Port these as editable shadcn/ui-style React source (not an opaque package). Each has a focused reference — read the one you need:

The Next.js→Vite/Hono porting surface (env vars, the @/@shared alias, the two server endpoints) is in references/vite-hono-porting.md.

Quick start

1. Install the frontend SDK

npm install @freemius/checkout

2. Prime the provider with a server-created checkout

// The base checkout is created server-side (freemius-core) and exposed at
// GET /api/checkout → { options, link, baseUrl }. Load it, then wrap the UI.
const checkout = await getBaseCheckout(); // CheckoutSerialized

<CheckoutProvider
  checkout={checkout}
  syncEndpoint="/api/purchase" // POST target for the success callback
  fetcher={portalFetch} // attaches auth headers
  // re-fetch entitlement after success
>
  <Subscribe />
  <Topup />
</CheckoutProvider>;

3. Open the overlay for a chosen plan

const checkout = useCheckout();

// Subscription (with billing cycle):
checkout.open({
  plan_id: planId,
  billing_cycle: 'annual',
  show_confirmation_dialog: false, // default — the app shows its own success state
});

// One-off / top-up (consumable credits):
checkout.open({
  plan_id: planId,
  billing_cycle: 'lifetime',
  show_confirmation_dialog: false,
});

open() merges your params over the base options and wires the purchaseCompleted callback, which POSTs to syncEndpoint.

Default show_confirmation_dialog: false in every open() call (or bake it into the provider): Freemius' own post-purchase confirmation modal is skipped in favor of the app's success state — better UX, one dialog instead of two. Because the Freemius dialog is off, the app must show its own confirmation (next section).

In-app success message (after purchase)

With show_confirmation_dialog: false, the app owns the confirmation UX on both purchase paths:

• Overlay path — purchaseCompleted → the provider POSTs to /api/purchase (entitlement sync) → onPurchase fires. Use it to (1) re-fetch the entitlement/balance and (2) show a visible success state — a toast/banner like "Purchase complete — premium unlocked" (subscription) or "Credits added to your account" (top-up). Never complete a purchase silently.
• Hosted-redirect path — Freemius redirects back to your purchase-redirect handler (freemius-core → purchase-processing); its result page must render the same success message.

See references/checkout-provider.md → "In-app success message" for the wiring.

Mental model

Server (freemius-core)              Frontend (this Skill)                 Freemius
  GET /api/checkout ───────────────▶ getBaseCheckout()
  { options, link, baseUrl } ──────▶ new Checkout(options,…) (one instance)
  GET /api/checkout/pricing ───────▶ <Subscribe/> + <Topup/> tables
                                      user clicks "Subscribe"/"Buy"
                                      useCheckout().open({plan_id, billing_cycle}) ─▶ overlay
                                      user pays ───────────────────────────────────▶ license/payment
  POST /api/purchase ◀────────────── purchaseCompleted(data) callback
  (re-fetch + upsert entitlement)
  402 on gated feature ────────────▶ <Paywall/> shows the right table

Hosted-checkout fallback

If you can't load @freemius/checkout (or want the simplest path), every plan in the pricing response also carries a hosted checkoutLink. Navigate the browser to it; Freemius redirects back to your purchase-redirect handler (handled in freemius-core → purchase-processing). Prefer the overlay for UX; keep the link as a graceful degradation.

Dashboard configuration (hand to the human)

In the Freemius Developer Dashboard (https://dashboard.freemius.com/):

• Product → Plans → define each plan and its pricing. A plan with only a lifetime price (no monthly/annual) renders in the Topup table; plans with monthly/annual prices render in Subscribe.
• Top-up precondition: the one-off/top-up modality only appears if a lifetime-only plan exists in the product. If the maker wants top-ups (or you need to demo/validate that modality), ask them to create one first — treat it as an intake/precondition question, and hide the Topup table gracefully when oneoff comes back empty.
• Checkout → appearance / behaviour → optional overlay branding.
• The webhook + redirect URL setup is owned by freemius-core.

Granting what a purchase entitles the user to (feature unlock, credit balance) is server-side and owned by freemius-core — for top-up credits, follow freemius-core → entitlement-logic.md → "Usage-based / credit metering (top-up model)" (balance in a separate user-keyed table, never an extension of user_fs_entitlement).