diff --git a/internal/filesystems/map.go b/internal/filesystems/map.go
index 3ecb34e40..88e61b010 100644
--- a/internal/filesystems/map.go
+++ b/internal/filesystems/map.go
@@ -18,6 +18,19 @@ type wrapperFs struct {
 	fs.FS
 }
 
+// Embedding fs.FS hides the wrapped FS's optional interfaces, so forward them.
+// Not GlobFS: OsFS.Glob uses filepath.Glob, whose semantics differ from fs.Glob.
+
+func (w *wrapperFs) Stat(name string) (fs.FileInfo, error)      { return fs.Stat(w.FS, name) }
+func (w *wrapperFs) ReadDir(name string) ([]fs.DirEntry, error) { return fs.ReadDir(w.FS, name) }
+func (w *wrapperFs) ReadFile(name string) ([]byte, error)       { return fs.ReadFile(w.FS, name) }
+
+var (
+	_ fs.StatFS     = (*wrapperFs)(nil)
+	_ fs.ReadDirFS  = (*wrapperFs)(nil)
+	_ fs.ReadFileFS = (*wrapperFs)(nil)
+)
+
 // FileSystemMap stores a map of filesystems
 // the empty key will be overwritten to be the default key
 // it includes a default filesystem, based off the os fs
diff --git a/internal/filesystems/map_test.go b/internal/filesystems/map_test.go
new file mode 100644
index 000000000..cfcd5ec93
--- /dev/null
+++ b/internal/filesystems/map_test.go
@@ -0,0 +1,71 @@
+package filesystems
+
+import (
+	"io/fs"
+	"os"
+	"path/filepath"
+	"runtime"
+	"testing"
+	"testing/fstest"
+)
+
+type openCountingFS struct {
+	fstest.MapFS
+	opens int
+}
+
+func (o *openCountingFS) Open(name string) (fs.File, error) {
+	o.opens++
+	return o.MapFS.Open(name)
+}
+
+func TestWrapperFsStat(t *testing.T) {
+	for i, tc := range []struct {
+		hideStatFS bool
+		wantOpens  int
+	}{
+		{hideStatFS: false, wantOpens: 0},
+		{hideStatFS: true, wantOpens: 1},
+	} {
+		inner := &openCountingFS{MapFS: fstest.MapFS{"file": {Data: []byte("data")}}}
+		var fsys fs.FS = inner
+		if tc.hideStatFS {
+			fsys = struct{ fs.FS }{inner}
+		}
+		var m FileSystemMap
+		m.Register("test", fsys)
+		wrapped, _ := m.Get("test")
+
+		info, err := fs.Stat(wrapped, "file")
+		if err != nil {
+			t.Fatalf("Test %d: unexpected error: %v", i, err)
+		}
+		if info.Size() != 4 {
+			t.Errorf("Test %d: expected size 4, got %d", i, info.Size())
+		}
+		if inner.opens != tc.wantOpens {
+			t.Errorf("Test %d: expected %d opens, got %d", i, tc.wantOpens, inner.opens)
+		}
+	}
+}
+
+func TestDefaultFileSystemStatDoesNotOpen(t *testing.T) {
+	if runtime.GOOS == "windows" || os.Geteuid() == 0 {
+		t.Skip("needs a file that cannot be opened")
+	}
+	name := filepath.Join(t.TempDir(), "unreadable")
+	if err := os.WriteFile(name, []byte("data"), 0o000); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := DefaultFileSystem.Open(name); err == nil {
+		t.Fatal("expected open to fail")
+	}
+
+	info, err := fs.Stat(DefaultFileSystem, name)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if info.Size() != 4 {
+		t.Errorf("expected size 4, got %d", info.Size())
+	}
+}
diff --git a/modules/caddyhttp/fileserver/matcher_test.go b/modules/caddyhttp/fileserver/matcher_test.go
index 1a00924f2..9c42f91fb 100644
--- a/modules/caddyhttp/fileserver/matcher_test.go
+++ b/modules/caddyhttp/fileserver/matcher_test.go
@@ -870,3 +870,32 @@ func TestSizePoliciesWithEmptyFiles(t *testing.T) {
 		})
 	}
 }
+
+func BenchmarkFileMatcher(b *testing.B) {
+	for _, bc := range []struct {
+		name string
+		path string
+	}{
+		{name: "existing file", path: "/index.php"},
+		{name: "front controller", path: "/blog/my-post"},
+	} {
+		b.Run(bc.name, func(b *testing.B) {
+			m := &MatchFile{
+				fsmap:     &filesystems.FileSystemMap{},
+				Root:      "./testdata",
+				TryFiles:  []string{"{http.request.uri.path}", "{http.request.uri.path}/index.php", "index.php"},
+				TryPolicy: tryPolicyFirstExist,
+				SplitPath: []string{".php"},
+			}
+			req := &http.Request{URL: &url.URL{Path: bc.path}}
+			caddyhttp.NewTestReplacer(req)
+
+			b.ReportAllocs()
+			for b.Loop() {
+				if ok, err := m.MatchWithError(req); !ok || err != nil {
+					b.Fatalf("expected match, got %t, %v", ok, err)
+				}
+			}
+		})
+	}
+}