feat: add checkout ui and driver-based payments

.gitignore

@@ -1 +1,2 @@
 *cache
+*env*

config/config.go

@@ -97,7 +97,9 @@ func applyEnvFile(path string) (retErr error) {
 
 		key := strings.TrimSpace(parts[0])
 		value := strings.TrimSpace(parts[1])
-		_ = os.Setenv(key, value)
+		if _, exists := os.LookupEnv(key); !exists {
+			_ = os.Setenv(key, value)
+		}
 	}
 
 	if err := scanner.Err(); err != nil {

internal/payments/driver/stripe/checkout.go

@@ -0,0 +1,69 @@
+package stripe
+
+import (
+	"context"
+	"errors"
+
+	stripesdk "github.com/stripe/stripe-go/v78"
+	"github.com/stripe/stripe-go/v78/client"
+
+	"github.com/rjNemo/payit/config"
+	"github.com/rjNemo/payit/internal/payments"
+)
+
+type sessionCreator interface {
+	New(params *stripesdk.CheckoutSessionParams) (*stripesdk.CheckoutSession, error)
+}
+
+// Driver implements the CheckoutDriver interface using the Stripe SDK.
+type Driver struct {
+	product  config.ProductConfig
+	sessions sessionCreator
+}
+
+// NewDriver creates a Stripe-backed checkout driver with the provided credentials.
+func NewDriver(apiKey string, product config.ProductConfig) *Driver {
+	stripeClient := client.New(apiKey, nil)
+
+	return &Driver{
+		product:  product,
+		sessions: stripeClient.CheckoutSessions,
+	}
+}
+
+// CreateSession delegates session creation to Stripe, translating domain values to SDK params.
+func (d *Driver) CreateSession(ctx context.Context, req payments.CheckoutSessionRequest) (payments.CheckoutSessionResult, error) {
+	quantity := req.Quantity
+	if quantity <= 0 {
+		quantity = 1
+	}
+
+	params := &stripesdk.CheckoutSessionParams{}
+	params.Context = ctx
+	params.SuccessURL = stripesdk.String(d.product.SuccessURL)
+	params.CancelURL = stripesdk.String(d.product.CancelURL)
+	params.Mode = stripesdk.String(string(stripesdk.CheckoutSessionModePayment))
+	params.PaymentMethodTypes = stripesdk.StringSlice([]string{"card"})
+
+	params.LineItems = append(params.LineItems, &stripesdk.CheckoutSessionLineItemParams{
+		Quantity: stripesdk.Int64(quantity),
+		PriceData: &stripesdk.CheckoutSessionLineItemPriceDataParams{
+			Currency:   stripesdk.String(d.product.Currency),
+			UnitAmount: stripesdk.Int64(d.product.PriceCents),
+			ProductData: &stripesdk.CheckoutSessionLineItemPriceDataProductDataParams{
+				Name:        stripesdk.String(d.product.Name),
+				Description: stripesdk.String(d.product.Description),
+			},
+		},
+	})
+
+	session, err := d.sessions.New(params)
+	if err != nil {
+		return payments.CheckoutSessionResult{}, err
+	}
+	if session == nil {
+		return payments.CheckoutSessionResult{}, errors.New("stripe returned nil session")
+	}
+
+	return payments.CheckoutSessionResult{ID: session.ID, URL: session.URL}, nil
+}

internal/payments/driver/stripe/checkout_test.go

@@ -5,33 +5,35 @@ import (
 	"errors"
 	"testing"
 
+	stripesdk "github.com/stripe/stripe-go/v78"
+
 	"github.com/rjNemo/payit/config"
-	stripeapi "github.com/stripe/stripe-go/v78"
+	"github.com/rjNemo/payit/internal/payments"
 )
 
 type fakeSessionCreator struct {
-	lastParams *stripeapi.CheckoutSessionParams
+	lastParams *stripesdk.CheckoutSessionParams
-	result     *stripeapi.CheckoutSession
+	result     *stripesdk.CheckoutSession
 	err        error
 }
 
-func (f *fakeSessionCreator) New(params *stripeapi.CheckoutSessionParams) (*stripeapi.CheckoutSession, error) {
+func (f *fakeSessionCreator) New(params *stripesdk.CheckoutSessionParams) (*stripesdk.CheckoutSession, error) {
 	f.lastParams = params
 	return f.result, f.err
 }
 
-func TestService_CreateSessionSuccess(t *testing.T) {
+func TestDriver_CreateSessionSuccess(t *testing.T) {
 	product := testProductConfig()
 	fake := &fakeSessionCreator{
-		result: &stripeapi.CheckoutSession{
+		result: &stripesdk.CheckoutSession{
 			ID:  "cs_test_123",
 			URL: "https://stripe.test/checkout",
 		},
 	}
 
-	svc := &Service{product: product, sessions: fake}
+	driver := &Driver{product: product, sessions: fake}
 
-	res, err := svc.CreateSession(context.Background(), CheckoutSessionRequest{})
+	res, err := driver.CreateSession(context.Background(), payments.CheckoutSessionRequest{})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -47,7 +49,7 @@ func TestService_CreateSessionSuccess(t *testing.T) {
 	if params.Context == nil {
 		t.Fatal("expected context to propagate")
 	}
-	if params.Mode == nil || *params.Mode != string(stripeapi.CheckoutSessionModePayment) {
+	if params.Mode == nil || *params.Mode != string(stripesdk.CheckoutSessionModePayment) {
 		t.Fatalf("unexpected mode: %v", params.Mode)
 	}
 	if len(params.PaymentMethodTypes) != 1 || params.PaymentMethodTypes[0] == nil || *params.PaymentMethodTypes[0] != "card" {
@@ -82,15 +84,15 @@ func TestService_CreateSessionSuccess(t *testing.T) {
 	}
 }
 
-func TestService_CreateSessionWithCustomQuantity(t *testing.T) {
+func TestDriver_CreateSessionWithCustomQuantity(t *testing.T) {
 	product := testProductConfig()
 	fake := &fakeSessionCreator{
-		result: &stripeapi.CheckoutSession{},
+		result: &stripesdk.CheckoutSession{},
 	}
 
-	svc := &Service{product: product, sessions: fake}
+	driver := &Driver{product: product, sessions: fake}
 
-	_, err := svc.CreateSession(context.Background(), CheckoutSessionRequest{Quantity: 3})
+	_, err := driver.CreateSession(context.Background(), payments.CheckoutSessionRequest{Quantity: 3})
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -106,25 +108,25 @@ func TestService_CreateSessionWithCustomQuantity(t *testing.T) {
 	}
 }
 
-func TestService_CreateSessionError(t *testing.T) {
+func TestDriver_CreateSessionError(t *testing.T) {
 	product := testProductConfig()
 	fake := &fakeSessionCreator{err: errors.New("boom")}
 
-	svc := &Service{product: product, sessions: fake}
+	driver := &Driver{product: product, sessions: fake}
 
-	_, err := svc.CreateSession(context.Background(), CheckoutSessionRequest{})
+	_, err := driver.CreateSession(context.Background(), payments.CheckoutSessionRequest{})
 	if err == nil {
 		t.Fatal("expected error")
 	}
 }
 
-func TestService_CreateSessionNilSession(t *testing.T) {
+func TestDriver_CreateSessionNilSession(t *testing.T) {
 	product := testProductConfig()
 	fake := &fakeSessionCreator{}
 
-	svc := &Service{product: product, sessions: fake}
+	driver := &Driver{product: product, sessions: fake}
 
-	_, err := svc.CreateSession(context.Background(), CheckoutSessionRequest{})
+	_, err := driver.CreateSession(context.Background(), payments.CheckoutSessionRequest{})
 	if err == nil {
 		t.Fatal("expected error for nil session")
 	}

internal/payments/service/checkout.go

@@ -0,0 +1,31 @@
+package service
+
+import (
+	"context"
+
+	"github.com/rjNemo/payit/internal/payments"
+)
+
+// CheckoutDriver represents a payment provider capable of creating checkout sessions.
+type CheckoutDriver interface {
+	CreateSession(ctx context.Context, req payments.CheckoutSessionRequest) (payments.CheckoutSessionResult, error)
+}
+
+// CheckoutService contains provider-agnostic business rules for initiating checkout flows.
+type CheckoutService struct {
+	driver CheckoutDriver
+}
+
+// NewCheckoutService wires the given driver into a reusable checkout service.
+func NewCheckoutService(driver CheckoutDriver) *CheckoutService {
+	return &CheckoutService{driver: driver}
+}
+
+// CreateSession applies domain defaults before delegating to the configured driver.
+func (s *CheckoutService) CreateSession(ctx context.Context, req payments.CheckoutSessionRequest) (payments.CheckoutSessionResult, error) {
+	if req.Quantity <= 0 {
+		req.Quantity = 1
+	}
+
+	return s.driver.CreateSession(ctx, req)
+}

internal/payments/service/checkout_test.go

@@ -0,0 +1,61 @@
+package service
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"github.com/rjNemo/payit/internal/payments"
+)
+
+type fakeDriver struct {
+	lastReq payments.CheckoutSessionRequest
+	result  payments.CheckoutSessionResult
+	err     error
+}
+
+func (f *fakeDriver) CreateSession(ctx context.Context, req payments.CheckoutSessionRequest) (payments.CheckoutSessionResult, error) {
+	f.lastReq = req
+	if f.err != nil {
+		return payments.CheckoutSessionResult{}, f.err
+	}
+	return f.result, nil
+}
+
+func TestCheckoutService_DefaultQuantity(t *testing.T) {
+	drv := &fakeDriver{}
+	svc := NewCheckoutService(drv)
+
+	_, err := svc.CreateSession(context.Background(), payments.CheckoutSessionRequest{})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	if drv.lastReq.Quantity != 1 {
+		t.Fatalf("expected default quantity 1, got %d", drv.lastReq.Quantity)
+	}
+}
+
+func TestCheckoutService_PreservesQuantity(t *testing.T) {
+	drv := &fakeDriver{}
+	svc := NewCheckoutService(drv)
+
+	_, err := svc.CreateSession(context.Background(), payments.CheckoutSessionRequest{Quantity: 5})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	if drv.lastReq.Quantity != 5 {
+		t.Fatalf("expected quantity 5, got %d", drv.lastReq.Quantity)
+	}
+}
+
+func TestCheckoutService_PropagatesError(t *testing.T) {
+	drv := &fakeDriver{err: errors.New("driver failed")}
+	svc := NewCheckoutService(drv)
+
+	_, err := svc.CreateSession(context.Background(), payments.CheckoutSessionRequest{Quantity: 2})
+	if err == nil {
+		t.Fatal("expected error from driver")
+	}
+}

internal/payments/types.go

@@ -1,4 +1,4 @@
-package stripe
+package payments
 
 // CheckoutSessionRequest captures optional inputs for creating a checkout session.
 type CheckoutSessionRequest struct {

internal/stripe/client.go

@@ -1,67 +0,0 @@
-package stripe
-
-import (
-	"context"
-	"errors"
-
-	"github.com/rjNemo/payit/config"
-	stripe "github.com/stripe/stripe-go/v78"
-	"github.com/stripe/stripe-go/v78/client"
-)
-
-type sessionCreator interface {
-	New(params *stripe.CheckoutSessionParams) (*stripe.CheckoutSession, error)
-}
-
-// Service coordinates Stripe Checkout session creation for the demo product.
-type Service struct {
-	product  config.ProductConfig
-	sessions sessionCreator
-}
-
-// NewService instantiates a Stripe-backed checkout service using the provided API key.
-func NewService(apiKey string, product config.ProductConfig) *Service {
-	stripeClient := client.New(apiKey, nil)
-
-	return &Service{
-		product:  product,
-		sessions: stripeClient.CheckoutSessions,
-	}
-}
-
-// CreateSession creates a Stripe Checkout session for the configured demo product.
-func (s *Service) CreateSession(ctx context.Context, req CheckoutSessionRequest) (CheckoutSessionResult, error) {
-	quantity := req.Quantity
-	if quantity <= 0 {
-		quantity = 1
-	}
-
-	params := &stripe.CheckoutSessionParams{}
-	params.Context = ctx
-	params.SuccessURL = stripe.String(s.product.SuccessURL)
-	params.CancelURL = stripe.String(s.product.CancelURL)
-	params.Mode = stripe.String(string(stripe.CheckoutSessionModePayment))
-	params.PaymentMethodTypes = stripe.StringSlice([]string{"card"})
-
-	params.LineItems = append(params.LineItems, &stripe.CheckoutSessionLineItemParams{
-		Quantity: stripe.Int64(quantity),
-		PriceData: &stripe.CheckoutSessionLineItemPriceDataParams{
-			Currency:   stripe.String(s.product.Currency),
-			UnitAmount: stripe.Int64(s.product.PriceCents),
-			ProductData: &stripe.CheckoutSessionLineItemPriceDataProductDataParams{
-				Name:        stripe.String(s.product.Name),
-				Description: stripe.String(s.product.Description),
-			},
-		},
-	})
-
-	session, err := s.sessions.New(params)
-	if err != nil {
-		return CheckoutSessionResult{}, err
-	}
-	if session == nil {
-		return CheckoutSessionResult{}, errors.New("stripe returned nil session")
-	}
-
-	return CheckoutSessionResult{ID: session.ID, URL: session.URL}, nil
-}

internal/web/handlers.go

@@ -6,17 +6,16 @@ import (
 	"io"
 	"net/http"
 
-	stripe "github.com/rjNemo/payit/internal/stripe"
+	"github.com/rjNemo/payit/internal/payments"
 )
 
 func (h *Handler) createCheckoutSession(w http.ResponseWriter, r *http.Request) {
-	var req stripe.CheckoutSessionRequest
+	var req payments.CheckoutSessionRequest
 
 	if r.Body != nil {
 		defer func(body io.ReadCloser) {
 			_ = body.Close()
 		}(r.Body)
-
 		dec := json.NewDecoder(r.Body)
 		dec.DisallowUnknownFields()
 

internal/web/handlers_test.go

@@ -9,19 +9,19 @@ import (
 	"net/http/httptest"
 	"testing"
 
-	stripe "github.com/rjNemo/payit/internal/stripe"
+	"github.com/rjNemo/payit/internal/payments"
 )
 
 type fakeCheckoutService struct {
-	result stripe.CheckoutSessionResult
+	result payments.CheckoutSessionResult
 	err    error
-	req    stripe.CheckoutSessionRequest
+	req    payments.CheckoutSessionRequest
 }
 
-func (f *fakeCheckoutService) CreateSession(ctx context.Context, req stripe.CheckoutSessionRequest) (stripe.CheckoutSessionResult, error) {
+func (f *fakeCheckoutService) CreateSession(ctx context.Context, req payments.CheckoutSessionRequest) (payments.CheckoutSessionResult, error) {
 	f.req = req
 	if f.err != nil {
-		return stripe.CheckoutSessionResult{}, f.err
+		return payments.CheckoutSessionResult{}, f.err
 	}
 	return f.result, nil
 }
@@ -29,7 +29,7 @@ func (f *fakeCheckoutService) CreateSession(ctx context.Context, req stripe.Chec
 func TestCreateCheckoutSessionSuccess(t *testing.T) {
 	handler := &Handler{
 		checkout: &fakeCheckoutService{
-			result: stripe.CheckoutSessionResult{ID: "cs_test_1", URL: "https://stripe.test/checkout"},
+			result: payments.CheckoutSessionResult{ID: "cs_test_1", URL: "https://stripe.test/checkout"},
 		},
 	}
 
@@ -47,7 +47,7 @@ func TestCreateCheckoutSessionSuccess(t *testing.T) {
 		t.Fatalf("expected json content type, got %s", ct)
 	}
 
-	var payload stripe.CheckoutSessionResult
+	var payload payments.CheckoutSessionResult
 	if err := json.Unmarshal(rec.Body.Bytes(), &payload); err != nil {
 		t.Fatalf("expected valid json response: %v", err)
 	}
@@ -63,7 +63,7 @@ func TestCreateCheckoutSessionSuccess(t *testing.T) {
 
 func TestCreateCheckoutSessionDefaultsQuantity(t *testing.T) {
 	fakeSvc := &fakeCheckoutService{
-		result: stripe.CheckoutSessionResult{ID: "cs_test_1"},
+		result: payments.CheckoutSessionResult{ID: "cs_test_1"},
 	}
 	handler := &Handler{checkout: fakeSvc}
 

internal/web/page.go

@@ -0,0 +1,30 @@
+package web
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+)
+
+type checkoutPageData struct {
+	ProductName        string
+	ProductDescription string
+	PriceDisplay       string
+	Currency           string
+}
+
+func (h *Handler) renderCheckoutPage(w http.ResponseWriter, r *http.Request) {
+	price := float64(h.cfg.Product.PriceCents) / 100
+	data := checkoutPageData{
+		ProductName:        h.cfg.Product.Name,
+		ProductDescription: h.cfg.Product.Description,
+		PriceDisplay:       fmt.Sprintf("$%.2f", price),
+		Currency:           strings.ToUpper(h.cfg.Product.Currency),
+	}
+
+	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+	if err := h.page.ExecuteTemplate(w, "index.html", data); err != nil {
+		http.Error(w, "failed to render page", http.StatusInternalServerError)
+		return
+	}
+}

internal/web/server.go

@@ -2,30 +2,45 @@ package web
 
 import (
 	"context"
+	"fmt"
+	"html/template"
+	"io/fs"
 	"net/http"
 
-	stripe "github.com/rjNemo/payit/internal/stripe"
-
 	"github.com/rjNemo/payit/config"
+	"github.com/rjNemo/payit/internal/payments"
+	"github.com/rjNemo/payit/internal/payments/driver/stripe"
+	"github.com/rjNemo/payit/internal/payments/service"
+	webassets "github.com/rjNemo/payit/web"
 )
 
 type checkoutService interface {
-	CreateSession(context.Context, stripe.CheckoutSessionRequest) (stripe.CheckoutSessionResult, error)
+	CreateSession(context.Context, payments.CheckoutSessionRequest) (payments.CheckoutSessionResult, error)
 }
 
 // Handler aggregates dependencies required by HTTP handlers.
 type Handler struct {
 	cfg      config.Config
 	checkout checkoutService
+	page     *template.Template
 }
 
 // NewServer constructs the root HTTP handler, wiring Stripe-backed endpoints as they are implemented.
 func NewServer(cfg config.Config) http.Handler {
-	checkoutSvc := stripe.NewService(cfg.StripeSecretKey, cfg.Product)
+	driver := stripe.NewDriver(cfg.StripeSecretKey, cfg.Product)
-	h := &Handler{cfg: cfg, checkout: checkoutSvc}
+	checkoutSvc := service.NewCheckoutService(driver)
+	tmpl := template.Must(template.ParseFS(webassets.Assets, "templates/index.html"))
+	staticFS, err := fs.Sub(webassets.Assets, "static")
+	if err != nil {
+		panic(fmt.Errorf("failed to load static assets: %w", err))
+	}
+
+	h := &Handler{cfg: cfg, checkout: checkoutSvc, page: tmpl}
 
 	mux := http.NewServeMux()
 	mux.HandleFunc("POST /api/checkout", h.createCheckoutSession)
+	mux.Handle("GET /", http.HandlerFunc(h.renderCheckoutPage))
+	mux.Handle("GET /static/", http.StripPrefix("/static/", http.FileServer(http.FS(staticFS))))
 
 	return mux
 }

web/embed.go

@@ -0,0 +1,8 @@
+package webassets
+
+import "embed"
+
+// Assets bundles HTML templates and static files for the checkout UI.
+//
+//go:embed templates/*.html static/*
+var Assets embed.FS

web/static/app.js

@@ -0,0 +1,59 @@
+(() => {
+  const form = document.getElementById('checkout-form');
+  const button = document.getElementById('checkout-button');
+  const qtyInput = document.getElementById('quantity');
+  const message = document.getElementById('message');
+
+  if (!form || !button || !qtyInput) {
+    return;
+  }
+
+  const setMessage = (text, isError = true) => {
+    if (!message) {
+      return;
+    }
+    message.textContent = text;
+    message.style.color = isError ? '#dc2626' : '#16a34a';
+  };
+
+  form.addEventListener('submit', async (event) => {
+    event.preventDefault();
+
+    const quantity = Number.parseInt(qtyInput.value, 10);
+    if (!Number.isFinite(quantity) || quantity <= 0) {
+      setMessage('Enter a quantity of at least 1.');
+      qtyInput.focus();
+      return;
+    }
+
+    try {
+      button.disabled = true;
+      setMessage('Contacting Stripe…', false);
+
+      const response = await fetch('/api/checkout', {
+        method: 'POST',
+        headers: {
+          'Content-Type': 'application/json',
+        },
+        body: JSON.stringify({ quantity }),
+      });
+
+      if (!response.ok) {
+        const errorText = await response.text();
+        throw new Error(errorText || 'Checkout request failed.');
+      }
+
+      const data = await response.json();
+      if (!data || !data.url) {
+        throw new Error('Checkout response missing redirect URL.');
+      }
+
+      setMessage('Redirecting to Stripe…', false);
+      window.location.href = data.url;
+    } catch (err) {
+      console.error('Checkout failed', err);
+      setMessage('Unable to start checkout. Please try again.');
+      button.disabled = false;
+    }
+  });
+})();

web/templates/index.html

@@ -0,0 +1,102 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1" />
+    <title>PayIt Checkout</title>
+    <link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=Inter:wght@400;600&display=swap" />
+    <style>
+      :root {
+        color-scheme: light dark;
+        font-family: "Inter", system-ui, -apple-system, sans-serif;
+        line-height: 1.5;
+      }
+      body {
+        margin: 0;
+        display: flex;
+        min-height: 100vh;
+        background: radial-gradient(circle at top, #fdfbfb, #ebedee);
+        justify-content: center;
+        align-items: center;
+        padding: 2rem;
+      }
+      .card {
+        background: rgba(255, 255, 255, 0.95);
+        border-radius: 18px;
+        box-shadow: 0 20px 45px rgba(15, 23, 42, 0.12);
+        padding: 2.5rem;
+        max-width: 420px;
+        width: 100%;
+      }
+      h1 {
+        margin-top: 0;
+        font-size: 1.75rem;
+        color: #0f172a;
+      }
+      p {
+        margin: 0.5rem 0 1.5rem;
+        color: #475569;
+      }
+      .price {
+        font-size: 1.5rem;
+        font-weight: 600;
+        color: #2563eb;
+        margin-bottom: 1.5rem;
+      }
+      form {
+        display: flex;
+        flex-direction: column;
+        gap: 1.25rem;
+      }
+      label {
+        font-weight: 600;
+        color: #1e293b;
+      }
+      input[type="number"] {
+        width: 100%;
+        padding: 0.75rem 1rem;
+        border-radius: 12px;
+        border: 1px solid #cbd5f5;
+        font-size: 1rem;
+      }
+      button {
+        background: linear-gradient(135deg, #2563eb, #7c3aed);
+        border: none;
+        border-radius: 12px;
+        color: #fff;
+        font-size: 1rem;
+        font-weight: 600;
+        padding: 0.9rem 1.2rem;
+        cursor: pointer;
+        transition: transform 0.15s ease, box-shadow 0.15s ease;
+      }
+      button:hover:not([disabled]) {
+        transform: translateY(-1px);
+        box-shadow: 0 12px 30px rgba(37, 99, 235, 0.25);
+      }
+      button[disabled] {
+        opacity: 0.65;
+        cursor: wait;
+      }
+      #message {
+        min-height: 1.5rem;
+        color: #dc2626;
+        font-size: 0.95rem;
+      }
+    </style>
+  </head>
+  <body>
+    <main class="card">
+      <h1>{{ .ProductName }}</h1>
+      <p>{{ .ProductDescription }}</p>
+      <div class="price">{{ .PriceDisplay }} <span class="currency">{{ .Currency }}</span></div>
+      <form id="checkout-form">
+        <label for="quantity">Quantity</label>
+        <input id="quantity" name="quantity" type="number" value="1" min="1" />
+        <button id="checkout-button" type="submit">Buy now</button>
+      </form>
+      <div id="message" role="status" aria-live="polite"></div>
+    </main>
+    <script src="/static/app.js" defer></script>
+  </body>
+</html>