diff --git a/cmd/godoc/x.go b/cmd/godoc/x.go
new file mode 100644
index 00000000..ed7c8d8a
--- /dev/null
+++ b/cmd/godoc/x.go
@@ -0,0 +1,68 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file contains the handlers that serve go-import redirects for Go
+// sub-repositories. It specifies the mapping from import paths like
+// "golang.org/x/tools" to the actual repository locations.
+
+package main
+
+import (
+ "html/template"
+ "log"
+ "net/http"
+ "strings"
+)
+
+const xPrefix = "/x/"
+
+var xMap = map[string]string{
+ "benchmarks": "https://code.google.com/p/go.benchmarks",
+ "blog": "https://code.google.com/p/go.blog",
+ "codereview": "https://code.google.com/p/go.codereview",
+ "crypto": "https://code.google.com/p/go.crypto",
+ "exp": "https://code.google.com/p/go.exp",
+ "image": "https://code.google.com/p/go.image",
+ "mobile": "https://code.google.com/p/go.mobile",
+ "net": "https://code.google.com/p/go.net",
+ "sys": "https://code.google.com/p/go.sys",
+ "talks": "https://code.google.com/p/go.talks",
+ "text": "https://code.google.com/p/go.text",
+ "tools": "https://code.google.com/p/go.tools",
+}
+
+func init() {
+ http.HandleFunc(xPrefix, xHandler)
+}
+
+func xHandler(w http.ResponseWriter, r *http.Request) {
+ head, tail := strings.TrimPrefix(r.URL.Path, xPrefix), ""
+ if i := strings.Index(head, "/"); i != -1 {
+ head, tail = head[:i], head[i:]
+ }
+ repo, ok := xMap[head]
+ if !ok {
+ http.NotFound(w, r)
+ return
+ }
+ data := struct {
+ Prefix, Head, Tail, Repo string
+ }{xPrefix, head, tail, repo}
+ if err := xTemplate.Execute(w, data); err != nil {
+ log.Println("xHandler:", err)
+ }
+}
+
+var xTemplate = template.Must(template.New("x").Parse(`
+
+
+
+
+
+
+
+Nothing to see here; move along.
+
+
+`))