diff --git a/BTCPayServer/wwwroot/shopify/btcpay-browser-client.js b/BTCPayServer/wwwroot/shopify/btcpay-browser-client.js
new file mode 100644
index 000000000..d73aa9804
--- /dev/null
+++ b/BTCPayServer/wwwroot/shopify/btcpay-browser-client.js
@@ -0,0 +1,88 @@
+/* Based on @djseeds script: https://github.com/btcpayserver/btcpayserver/issues/36#issuecomment-633109155 */
+/*** Creates a new BTCPayServer Modal
+ * @param url - BTCPayServer Base URL
+ * @param storeId - BTCPayServer store ID
+ * @param data - Data to use for invoice creation
+* @returns - A promise that resolves when invoice is paid.
+* ***/
+var BtcPayServerModal = (function () {
+    function waitForPayment(btcPayServerUrl, invoiceId, storeId) {
+        // Todo: mutex lock on btcpayserver modal.
+        return new Promise(function (resolve, reject) {
+            // Don't allow two modals at once.
+            if (waitForPayment.lock) {
+                resolve(null);
+            }
+            else {
+                waitForPayment.lock = true;
+            }
+            window.btcpay.onModalWillEnter(function () {
+                var interval = setInterval(function () {
+                    getBtcPayInvoice(btcPayServerUrl, invoiceId, storeId)
+                        .then(function (invoice) {
+                            if (invoice.status == "complete") {
+                                clearInterval(interval);
+                                resolve(invoice);
+                            }
+                        })
+                        .catch(function (err) {
+                            clearInterval(interval);
+                            reject(err);
+                        });
+                }, 1000);
+                window.btcpay.onModalWillLeave(function () {
+                    waitForPayment.lock = false;
+                    clearInterval(interval);
+                    // If user exited the payment modal,
+                    // indicate that there was no error but invoice did not complete.
+                    resolve(null);
+                });
+            });
+            window.btcpay.showInvoice(invoiceId);
+        });
+    }
+
+    function getBtcPayInvoice(btcPayServerUrl, invoiceId, storeId) {
+        const url = btcPayServerUrl + "/invoices/" + invoiceId + "?storeId=" + storeId;
+        return fetch(url, {
+            method: "GET",
+            mode: "cors", // no-cors, cors, *same-origin,
+            headers: {
+                "Content-Type": "application/json",
+                "accept": "application/json",
+            }
+        })
+            .then(function (response) {
+                return response.json();
+            })
+            .then(function (json) {
+                return json.data;
+            })
+    }
+
+    return {
+        show: function (url, storeId, data) {
+            const path = url + "/invoices?storeId=" + storeId;
+            return fetch(path,
+                {
+                    method: "POST",
+                    mode: "cors",
+                    headers: {
+                        "Content-Type": "application/json",
+                        "accept": "application/json",
+                    },
+                    body: JSON.stringify(data)
+                }
+            )
+                .then(function (response) {
+                    return response.json();
+                })
+                .then(function (response) {
+                    return waitForPayment(url, response.data.id, storeId);
+                });
+        },
+        hide: function () {
+            window.btcpay.hideFrame();
+        }
+    }
+})()
diff --git a/BTCPayServer/wwwroot/shopify/btcpay-shopify-checkout.js b/BTCPayServer/wwwroot/shopify/btcpay-shopify-checkout.js
new file mode 100644
index 000000000..c736b9315
--- /dev/null
+++ b/BTCPayServer/wwwroot/shopify/btcpay-shopify-checkout.js
@@ -0,0 +1,138 @@
+/* Based on @djseeds script: https://github.com/btcpayserver/btcpayserver/issues/36#issuecomment-633109155 */
+
+/*
+ 
+1. In your BTCPayServer store you need to check "Allow anyone to create invoice"
+2. In Shopify Settings > Payment Providers > Manual Payment Methods add one which contains "Bitcoin"
+3. In Shopify Settings > Checkout > Additional Scripts input the following script, with the details from your BTCPayServer instead of the placeholder values.
+<script>
+    const BTCPAYSERVER_URL = "https://your-btcpay-server-url:port";
+    const STORE_ID = "your-btcpayserver-store-id";
+    const DEFAULT_CURRENCY_SYMBOL = "$";
+    const DEFAULT_CURRENCY = "USD";
+    const THOUSAND_DELIMITER = ",";
+</script>
+<script src="https://your-btcpay-server-url:port/modal/btcpay.js"></script>
+<script src="https://your-btcpay-server-url:port/shopify/btcpay-browser-client.js"></script>
+<script src="https://your-btcpay-server-url:port/shopify/btcpay-shopify-checkout.js"></script>
+
+ */
+
+! function () {
+    "use strict";
+    const pageElements = document.querySelector.bind(document),
+        insertElement = (document.querySelectorAll.bind(document),
+            (e,
+                n) => {
+                n.parentNode.insertBefore(e,
+                    n.nextSibling)
+            });
+
+    let pageItems = {},
+        pageheader = "Thank you!",
+        buttonElement = null;
+
+    const setPageItems = () => {
+        pageItems = {
+            mainHeader: pageElements("#main-header"),
+            orderConfirmed: pageElements(".os-step__title"),
+            orderConfirmedDescription: pageElements(".os-step__description"),
+            continueButton: pageElements(".step__footer__continue-btn"),
+            checkMarkIcon: pageElements(".os-header__hanging-icon"),
+            orderStatus: pageElements(".os-header__title"),
+            paymentMethod: pageElements(".payment-method-list__item__info"),
+            price: pageElements(".payment-due__price"),
+            finalPrice: pageElements(".total-recap__final-price"),
+            orderNumber: pageElements(".os-order-number"),
+        }
+    }
+
+    const orderPaid = () => {
+        pageItems.mainHeader.innerText = pageheader,
+            pageItems.orderConfirmed && (pageItems.orderConfirmed.style.display = "block"),
+            pageItems.orderConfirmedDescription && (pageItems.orderConfirmedDescription.style.display = "block"),
+            pageItems.continueButton && (pageItems.continueButton.style.visibility = "visible"),
+            pageItems.checkMarkIcon && (pageItems.checkMarkIcon.style.visibility = "visible"),
+            buttonElement && (buttonElement.style.display = "none");
+    };
+
+    window.setOrderAsPaid = orderPaid,
+        window.openBtcPayShopify = function waitForPaymentMethod() {
+            if (setPageItems(), "Order canceled" === pageItems.orderStatus.innerText) {
+                return;
+            }
+
+            const paymentMethod = pageItems.paymentMethod;
+
+            if (null === paymentMethod) {
+                return void setTimeout(() => {
+                    waitForPaymentMethod();
+                }, 10);
+            }
+
+            if (-1 === paymentMethod.innerText.toLowerCase().indexOf("bitcoin")) return;
+
+            // If payment method is bitcoin, display instructions and payment button.
+            pageheader = pageItems.mainHeader.innerText,
+                pageItems.mainHeader && (pageItems.mainHeader.innerText = "Review and pay!"),
+                pageItems.continueButton && (pageItems.continueButton.style.visibility = "hidden"),
+                pageItems.checkMarkIcon && (pageItems.checkMarkIcon.style.visibility = "hidden"),
+                pageItems.orderConfirmed && (pageItems.orderConfirmed.style.display = "none"),
+                pageItems.orderConfirmedDescription && (pageItems.orderConfirmedDescription.style.display = "none"),
+                buttonElement = document.createElement("div");
+
+            const priceElement = pageItems.finalPrice || pageItems.price;
+            var price = priceElement.innerText.replace(DEFAULT_CURRENCY_SYMBOL, "").replace(THOUSAND_DELIMITER, "");
+            if (THOUSAND_DELIMITER === ".") {
+                price = price.replace(",", "."); // 5.000,00 needs to become 5000.00
+            }
+            const orderId = pageItems.orderNumber.innerText.replace("Order #", "");
+
+            const url = BTCPAYSERVER_URL + "/invoices" + "?storeId=" + STORE_ID + "&orderId=" + orderId + "&status=complete";
+
+            // Check if already paid.
+            fetch(url, {
+                method: "GET",
+                mode: "cors", // no-cors, cors, *same-origin,
+                headers: {
+                    "Content-Type": "application/json",
+                    "accept": "application/json",
+                },
+            })
+                .then(function (response) {
+                    return response.json();
+                })
+                .then(function (json) {
+                    return json.data;
+                })
+                .then(function (data) {
+                    if (data.length != 0) {
+                        orderPaid();
+                    }
+                });
+
+            window.waitForPayment = function () {
+                BtcPayServerModal.show(
+                    BTCPAYSERVER_URL,
+                    STORE_ID,
+                    {
+                        price: price,
+                        currency: DEFAULT_CURRENCY,
+                        orderId: orderId
+                    }
+                )
+                    .then(function (invoice) {
+                        if (invoice != null) {
+                            orderPaid();
+                        }
+                    });
+            }
+
+            // Payment button that opens modal
+            buttonElement.innerHTML = `\n    <button class="btn btn-primary" onclick="window.waitForPayment()"/>Pay with BTCPayServer</button>\n`,
+                insertElement(buttonElement, pageItems.orderConfirmed);
+
+        }
+
+    window.openBtcPayShopify();
+}();