smartEngin buy turns your own WordPress site into a shop for digital products \u2014 documents, e-books, templates, any file you sell. There is no marketplace in between: your site takes the payment, writes the invoice and serves the download.<\/p>\n\n
No commission per sale. No foreign branding. No customer data at a third party.<\/strong> Everything runs in your own database; the only outside parties are the payment providers you switch on.<\/p>\n\n What you can sell<\/strong><\/p>\n\n Selling and getting paid<\/strong><\/p>\n\n Invoices and bookkeeping<\/strong><\/p>\n\n Your customers<\/strong><\/p>\n\n Setting it up with an AI assistant<\/strong><\/p>\n\n Stripe keys, webhooks, tax settings, invoice numbers \u2014 that is where most people get stuck. Under \"Help & docs\" one click copies a briefing about your<\/em> installation into ChatGPT or Claude, which then tells you what is still missing. No account, no setup, nothing leaves your site. If your assistant can read online by itself, an optional read-only connection lets it check your settings directly: off until you switch it on, never exposing a secret, never able to change anything, and it closes itself when its short-lived code expires.<\/p>\n\n Extensions<\/strong><\/p>\n\n This plugin connects to external services only when YOU switch them on and only to take a payment. Nothing is transmitted while they are switched off.<\/p>\n\n Stripe<\/strong><\/p>\n\n Used to take card payments and subscriptions when you enter your Stripe keys under Settings \u2192 Payment providers.<\/p>\n\n PayPal<\/strong><\/p>\n\n Used to take PayPal payments and subscriptions when you enter your PayPal credentials under Settings \u2192 Payment providers.<\/p>\n\n No other external service is contacted. The plugin does not phone home, does not collect statistics and does not load fonts, scripts or images from anywhere else.<\/p>\n\n The plugin stores what a purchase needs: name, e-mail address, billing address when your invoice settings require one, the ordered items and the invoice. This data lives in tables on your own site and is never sent anywhere but to the payment provider handling that payment.<\/p>\n\n Invoices are kept because tax law requires it; they are not deleted automatically. Secret keys (Stripe, PayPal) are never exported, never shown again after saving and never included in any support or setup output.<\/p>\n\n Beyond the purchase itself, the plugin keeps two short technical logs on your own site \u2014 for you as the site owner, and for nobody else:<\/p>\n\n Neither log is sent anywhere. \"Remove all data\" on uninstall clears both, along with everything else the plugin stored.<\/p>\n\n\n 1. Install and activate.<\/strong> Plugins \u2192 Add New \u2192 Upload, or copy the 2. Settings.<\/strong> Sender name and address for the invoices, your tax mode (standard or the German \u00a7 19 small-business rule) and the prefix for your invoice numbers. Set the prefix before the first sale \u2014 numbers are frozen once issued.<\/p>\n\n 3. Add a product.<\/strong> Products \u2192 Add: a name, at least one purchase option (one-time, monthly or yearly) and the file the buyer receives.<\/p>\n\n 4. Put the offer cards on a page.<\/strong> The block \"smartEngin Offer cards\", or 5. Try it in test mode first.<\/strong> Test mode is on until you switch it off. Buy your own product and you get the order, the invoice, the mail and the download \u2014 without a payment provider and without money moving.<\/p>\n\n 6. Then switch on real payments.<\/strong> Enter your Stripe or PayPal credentials \u2014 and set up the webhook the settings screen shows you.<\/strong> That is not optional: subscriptions, refunds and payments that send the buyer to another site (Klarna, Amazon Pay \u2026) are confirmed by the webhook, not by the browser. Without it a paid order can stay open. Test and live mode need separate webhooks at both providers.<\/p>\n\n Not sure whether everything is done? The Dashboard shows a checklist of what is still missing, and \"Help & docs\" explains every screen.<\/p>\n\n\n Nothing, with no time limit, and no commission on your sales. Only your payment provider charges its usual fee.<\/p><\/dd>\n Only to take real money. Stripe and PayPal are optional and switched off until you enter your credentials. The test mode runs a complete purchase without either.<\/p><\/dd>\n Everything WordPress itself accepts as an upload: PDF, ZIP, images, audio, video, office documents and so on. Executable software (EXE, MSI, DMG, APK) is not among them \u2014 WordPress blocks those uploads and this plugin does not widen the list.<\/p><\/dd>\n Yes, as soon as you take real money. Subscription renewals, refunds and every payment method that sends the buyer to another site are reported by the provider directly to your site, not by the buyer's browser \u2014 without the webhook a paid order can stay open. The settings screen shows the exact address; test and live mode need one each.<\/p><\/dd>\n Refund the payment in Stripe or PayPal; their webhook then writes the matching credit note here and updates the order. Provider events are never retroactive, so a refund made before the webhook existed produces none.<\/p><\/dd>\n They are printable HTML pages, which every browser saves as PDF.<\/p><\/dd>\n In its own database tables on your site. Nothing is sent anywhere except to the payment provider you switched on, and only what that payment needs.<\/p><\/dd>\n Yes. Monthly and yearly subscriptions run through Stripe or PayPal, and the plugin keeps access, invoices and reminders in step with them.<\/p><\/dd>\n Yes, with the free add-on smartEngin Courses<\/em>: trainings, courses, videos and a member area, sold through this plugin's checkout.<\/p><\/dd>\n Not this plugin. That is what smartEngin Licence & buy<\/em> is for \u2014 the same core plus licence keys, activation limits and an update server.<\/p><\/dd>\n The two are the same core and share their data tables, so they must never run side by side \u2014 loading both would break the site with duplicate class names. This plugin therefore never touches the other one: if smartEngin Licence & buy is active, activating this plugin is refused with a message asking you to deactivate that one first. You stay in control of which plugin runs, and nothing is deleted in either direction \u2014 products, orders, invoices, coupons and customer accounts are picked up unchanged.<\/p><\/dd>\n The plugin identifies visitors by the address the web server reports, on purpose: forwarded headers can be faked, and the abuse brakes and the security log must not be foolable. Most hosts restore the real visitor address automatically. If yours does not, every visitor appears to come from the proxy \u2014 the security log becomes useless and the purchase-attempt brake can catch genuine buyers. Ask your host to enable real-IP restoration (mod_remoteip, real_ip or their Cloudflare integration).<\/p><\/dd>\n\n<\/dl>\n\n\n\n
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[sels_cards product=\"your-product-slug\"]<\/code>. Buyers never leave the page.<\/li>\n[sels_preis]<\/code> writes the current price into your running text, so a price change leaves no stale number on a landing page.<\/li>\n<\/ul>\n\n\n
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External services<\/h3>\n\n
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https:\/\/api.stripe.com<\/code>. Card details are entered in Stripe's own form and go directly to Stripe \u2014 the plugin never sees or stores them.<\/li>\nhttps:\/\/js.stripe.com<\/code> \u2014 in the visitor's browser, and only once that visitor has actually started a card payment, never on page load. Stripe then reports the result of the payment back to your site.<\/li>\napi.stripe.com<\/code> (from your server), js.stripe.com<\/code> (from the visitor's browser). No other Stripe address is used.<\/li>\n\n
https:\/\/api-m.paypal.com<\/code> \u2014 or at https:\/\/api-m.sandbox.paypal.com<\/code> while you are testing with sandbox credentials. The customer signs in with PayPal directly; the plugin never sees those credentials.<\/li>\nhttps:\/\/www.paypal.com<\/code> \u2014 in the visitor's browser, and only once that visitor has actually started a PayPal payment, never on page load. PayPal then reports the result of the payment back to your site.<\/li>\napi-m.paypal.com<\/code> (or api-m.sandbox.paypal.com<\/code> in sandbox mode) from your server, and www.paypal.com<\/code> from the visitor's browser. No other PayPal address is used.<\/li>\nPrivacy<\/h3>\n\n
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smartengin-buy<\/code> folder to \/wp-content\/plugins\/<\/code>. A menu \"smartEngin buy\" appears.<\/p>\n\n[sels_cards product=\"your-product-slug\"]<\/code>. That is the whole shop front.<\/p>\n\n\n
What does it cost?<\/h3><\/dt>\n
Do I need an account with an external service?<\/h3><\/dt>\n
What kinds of file can I sell?<\/h3><\/dt>\n
Do I really have to set up a webhook?<\/h3><\/dt>\n
What happens when I refund a customer?<\/h3><\/dt>\n
Are the invoices PDF files?<\/h3><\/dt>\n
Where is my customer data stored?<\/h3><\/dt>\n
Does it work with subscriptions?<\/h3><\/dt>\n
Can I sell online courses with it?<\/h3><\/dt>\n
Can it license my own software?<\/h3><\/dt>\n
What happens when I switch to smartEngin Licence & buy, or back?<\/h3><\/dt>\n
My site runs behind Cloudflare or another proxy\/CDN \u2014 anything to watch out for?<\/h3><\/dt>\n
1.6.6<\/h4>\n\n
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