diff --git a/internal/imgcache/fetcher.go b/internal/imgcache/fetcher.go
index cfc1e7d..dd9f75e 100644
--- a/internal/imgcache/fetcher.go
+++ b/internal/imgcache/fetcher.go
@@ -13,12 +13,12 @@ import (
 
 // Fetcher configuration constants.
 const (
-	DefaultFetchTimeout     = 30 * time.Second
-	DefaultMaxResponseSize  = 50 << 20 // 50MB
-	DefaultTLSTimeout       = 10 * time.Second
-	DefaultMaxIdleConns     = 100
-	DefaultIdleConnTimeout  = 90 * time.Second
-	DefaultMaxRedirects     = 10
+	DefaultFetchTimeout    = 30 * time.Second
+	DefaultMaxResponseSize = 50 << 20 // 50MB
+	DefaultTLSTimeout      = 10 * time.Second
+	DefaultMaxIdleConns    = 100
+	DefaultIdleConnTimeout = 90 * time.Second
+	DefaultMaxRedirects    = 10
 )
 
 // Fetcher errors.
@@ -148,7 +148,7 @@ func (f *HTTPFetcher) Fetch(ctx context.Context, url string) (*FetchResult, erro
 
 	// Wrap body with size limiter
 	limitedBody := &limitedReader{
-		reader:   resp.Body,
+		reader:    resp.Body,
 		remaining: f.config.MaxResponseSize,
 	}
 
diff --git a/internal/imgcache/signature_test.go b/internal/imgcache/signature_test.go
index 46ea58a..ee6f99e 100644
--- a/internal/imgcache/signature_test.go
+++ b/internal/imgcache/signature_test.go
@@ -58,11 +58,11 @@ func TestSigner_Verify(t *testing.T) {
 			name: "valid signature",
 			setup: func() *ImageRequest {
 				req := &ImageRequest{
-					SourceHost:  "cdn.example.com",
-					SourcePath:  "/photos/cat.jpg",
-					Size:        Size{Width: 800, Height: 600},
-					Format:      FormatWebP,
-					Expires:     time.Now().Add(1 * time.Hour),
+					SourceHost: "cdn.example.com",
+					SourcePath: "/photos/cat.jpg",
+					Size:       Size{Width: 800, Height: 600},
+					Format:     FormatWebP,
+					Expires:    time.Now().Add(1 * time.Hour),
 				}
 				req.Signature = signer.Sign(req)
 
@@ -74,11 +74,11 @@ func TestSigner_Verify(t *testing.T) {
 			name: "expired signature",
 			setup: func() *ImageRequest {
 				req := &ImageRequest{
-					SourceHost:  "cdn.example.com",
-					SourcePath:  "/photos/cat.jpg",
-					Size:        Size{Width: 800, Height: 600},
-					Format:      FormatWebP,
-					Expires:     time.Now().Add(-1 * time.Hour), // Expired
+					SourceHost: "cdn.example.com",
+					SourcePath: "/photos/cat.jpg",
+					Size:       Size{Width: 800, Height: 600},
+					Format:     FormatWebP,
+					Expires:    time.Now().Add(-1 * time.Hour), // Expired
 				}
 				req.Signature = signer.Sign(req)
 
@@ -90,12 +90,12 @@ func TestSigner_Verify(t *testing.T) {
 			name: "invalid signature",
 			setup: func() *ImageRequest {
 				return &ImageRequest{
-					SourceHost:  "cdn.example.com",
-					SourcePath:  "/photos/cat.jpg",
-					Size:        Size{Width: 800, Height: 600},
-					Format:      FormatWebP,
-					Expires:     time.Now().Add(1 * time.Hour),
-					Signature:   "invalid-signature",
+					SourceHost: "cdn.example.com",
+					SourcePath: "/photos/cat.jpg",
+					Size:       Size{Width: 800, Height: 600},
+					Format:     FormatWebP,
+					Expires:    time.Now().Add(1 * time.Hour),
+					Signature:  "invalid-signature",
 				}
 			},
 			wantErr: ErrSignatureInvalid,
@@ -118,11 +118,11 @@ func TestSigner_Verify(t *testing.T) {
 			name: "tampered request",
 			setup: func() *ImageRequest {
 				req := &ImageRequest{
-					SourceHost:  "cdn.example.com",
-					SourcePath:  "/photos/cat.jpg",
-					Size:        Size{Width: 800, Height: 600},
-					Format:      FormatWebP,
-					Expires:     time.Now().Add(1 * time.Hour),
+					SourceHost: "cdn.example.com",
+					SourcePath: "/photos/cat.jpg",
+					Size:       Size{Width: 800, Height: 600},
+					Format:     FormatWebP,
+					Expires:    time.Now().Add(1 * time.Hour),
 				}
 				req.Signature = signer.Sign(req)
 				// Tamper with the request
@@ -157,11 +157,11 @@ func TestSigner_DifferentKeys(t *testing.T) {
 	signer2 := NewSigner("secret-key-2")
 
 	req := &ImageRequest{
-		SourceHost:  "cdn.example.com",
-		SourcePath:  "/photos/cat.jpg",
-		Size:        Size{Width: 800, Height: 600},
-		Format:      FormatWebP,
-		Expires:     time.Now().Add(1 * time.Hour),
+		SourceHost: "cdn.example.com",
+		SourcePath: "/photos/cat.jpg",
+		Size:       Size{Width: 800, Height: 600},
+		Format:     FormatWebP,
+		Expires:    time.Now().Add(1 * time.Hour),
 	}
 
 	// Sign with key 1