diff --git a/cmd/godoc/.gitignore b/cmd/godoc/.gitignore
new file mode 100644
index 00000000000..a02b5c6ee9f
--- /dev/null
+++ b/cmd/godoc/.gitignore
@@ -0,0 +1,3 @@
+index.split.*
+godoc.index
+godoc.zip
diff --git a/cmd/godoc/README.godoc-app b/cmd/godoc/README.godoc-app
index 50a051659db..94abf0cd4d8 100644
--- a/cmd/godoc/README.godoc-app
+++ b/cmd/godoc/README.godoc-app
@@ -1,56 +1,41 @@
-godoc on appengine
-------------------
+godoc on Google App Engine
+==========================
 
 Prerequisites
 -------------
 
-* Go appengine SDK
-  https://developers.google.com/appengine/downloads#Google_App_Engine_SDK_for_Go
+* Google Cloud SDK
+  https://cloud.google.com/sdk/
 
-* Go sources at tip under $GOROOT
+* Go sources under $GOROOT
 
-* Godoc sources at tip inside $GOPATH
+* Godoc sources inside $GOPATH
   (go get -d golang.org/x/tools/cmd/godoc)
 
 
-Directory structure
--------------------
+Running in dev_appserver.py
+---------------------------
 
-* Let $APPDIR be the directory containing the app engine files.
-  (e.g., $APPDIR=$HOME/godoc-app)
+Use dev_appserver.py to run the server in development mode:
 
-* $APPDIR contains the following entries (this may change depending on
-  app-engine release and version of godoc):
+	dev_appserver.py app.dev.yaml
 
-	app.yaml
-	golang.org/x/tools/cmd/godoc
-	godoc.zip
-	index.split.*
+To run the server with generated zip file and search index:
 
-* The app.yaml file is set up per app engine documentation.
-  For instance:
+	./generate-index.bash
+	dev_appserver.py app.prod.yaml
 
-	application: godoc-app
-	version: 1
-	runtime: go
-	api_version: go1
+godoc should come up at http://localhost:8080
+Use the --host and --port flags to listen on a different address.
 
-	handlers:
-	- url: /.*
-	  script: _go_app
+To clean up the index files, use git:
 
+	git clean -xn # n is dry run, replace with f
 
-Configuring and running godoc
------------------------------
 
-To configure godoc, run
+Troubleshooting
+---------------
 
-	bash setup-godoc-app.bash
-
-to prepare an $APPDIR as described above. See the script for details on usage.
-
-To run godoc locally, using the App Engine development server, run
-
-	<path to go_appengine>/dev_appserver.py $APPDIR
-
-godoc should come up at http://localhost:8080 .
+Ensure the Cloud SDK is on your PATH and you have the app-engine-go component
+installed (gcloud components install app-engine-go) and your components are
+up-to-date (gcloud components update)
diff --git a/cmd/godoc/app.dev.yaml b/cmd/godoc/app.dev.yaml
new file mode 100644
index 00000000000..0f8f1cc29f0
--- /dev/null
+++ b/cmd/godoc/app.dev.yaml
@@ -0,0 +1,13 @@
+runtime: go
+api_version: go1
+instance_class: F4_1G
+
+handlers:
+- url: /s
+  script: _go_app
+  login: admin
+- url: /dl/init
+  script: _go_app
+  login: admin
+- url: /.*
+  script: _go_app
diff --git a/cmd/godoc/app.prod.yaml b/cmd/godoc/app.prod.yaml
new file mode 100644
index 00000000000..6a18a647d39
--- /dev/null
+++ b/cmd/godoc/app.prod.yaml
@@ -0,0 +1,18 @@
+runtime: go
+api_version: go1
+instance_class: F4_1G
+
+handlers:
+- url: /s
+  script: _go_app
+  login: admin
+- url: /dl/init
+  script: _go_app
+  login: admin
+- url: /.*
+  script: _go_app
+
+env_variables:
+  GODOC_ZIP: godoc.zip
+  GODOC_ZIP_PREFIX: goroot
+  GODOC_INDEX_GLOB: 'index.split.*'
diff --git a/cmd/godoc/appinit.go b/cmd/godoc/appinit.go
index 66700dcf1be..e422d9cb266 100644
--- a/cmd/godoc/appinit.go
+++ b/cmd/godoc/appinit.go
@@ -13,8 +13,10 @@ import (
 	"archive/zip"
 	"log"
 	"net/http"
+	"os"
 	"path"
 	"regexp"
+	"runtime"
 
 	"golang.org/x/tools/godoc"
 	"golang.org/x/tools/godoc/dl"
@@ -22,12 +24,25 @@ import (
 	"golang.org/x/tools/godoc/short"
 	"golang.org/x/tools/godoc/static"
 	"golang.org/x/tools/godoc/vfs"
+	"golang.org/x/tools/godoc/vfs/gatefs"
 	"golang.org/x/tools/godoc/vfs/mapfs"
 	"golang.org/x/tools/godoc/vfs/zipfs"
 	"google.golang.org/appengine"
 )
 
 func init() {
+	var (
+		// .zip filename
+		zipFilename = os.Getenv("GODOC_ZIP")
+
+		// goroot directory in .zip file
+		zipGoroot = os.Getenv("GODOC_ZIP_PREFIX")
+
+		// glob pattern describing search index files
+		// (if empty, the index is built at run-time)
+		indexFilenames = os.Getenv("GODOC_INDEX_GLOB")
+	)
+
 	enforceHosts = !appengine.IsDevAppServer()
 	playEnabled = true
 
@@ -36,16 +51,20 @@ func init() {
 	log.Printf(".zip GOROOT = %s", zipGoroot)
 	log.Printf("index files = %s", indexFilenames)
 
-	goroot := path.Join("/", zipGoroot) // fsHttp paths are relative to '/'
-
-	// read .zip file and set up file systems
-	const zipfile = zipFilename
-	rc, err := zip.OpenReader(zipfile)
-	if err != nil {
-		log.Fatalf("%s: %s\n", zipfile, err)
+	if zipFilename != "" {
+		goroot := path.Join("/", zipGoroot) // fsHttp paths are relative to '/'
+		// read .zip file and set up file systems
+		rc, err := zip.OpenReader(zipFilename)
+		if err != nil {
+			log.Fatalf("%s: %s\n", zipFilename, err)
+		}
+		// rc is never closed (app running forever)
+		fs.Bind("/", zipfs.New(rc, zipFilename), goroot, vfs.BindReplace)
+	} else {
+		rootfs := gatefs.New(vfs.OS(runtime.GOROOT()), make(chan bool, 20))
+		fs.Bind("/", rootfs, "/", vfs.BindReplace)
 	}
-	// rc is never closed (app running forever)
-	fs.Bind("/", zipfs.New(rc, zipFilename), goroot, vfs.BindReplace)
+
 	fs.Bind("/lib/godoc", mapfs.New(static.Files), "/", vfs.BindReplace)
 
 	corpus := godoc.NewCorpus(fs)
diff --git a/cmd/godoc/generate-index.bash b/cmd/godoc/generate-index.bash
new file mode 100755
index 00000000000..38ac79ae84b
--- /dev/null
+++ b/cmd/godoc/generate-index.bash
@@ -0,0 +1,72 @@
+#!/usr/bin/env bash
+
+# Copyright 2011 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 script creates a .zip file representing the $GOROOT file system
+# and computes the corresponding search index files.
+#
+# These are used in production (see app.prod.yaml)
+
+set -e -u -x
+
+ZIPFILE=godoc.zip
+INDEXFILE=godoc.index
+SPLITFILES=index.split.
+
+error() {
+	echo "error: $1"
+	exit 2
+}
+
+install() {
+	go install
+}
+
+getArgs() {
+	if [ ! -v GOROOT ]; then
+		GOROOT="$(go env GOROOT)"
+		echo "GOROOT not set explicitly, using go env value instead"
+	fi
+
+	# safety checks
+	if [ ! -d "$GOROOT" ]; then
+		error "$GOROOT is not a directory"
+	fi
+
+	# reporting
+	echo "GOROOT = $GOROOT"
+}
+
+makeZipfile() {
+	echo "*** make $ZIPFILE"
+	rm -f $ZIPFILE goroot
+	ln -s "$GOROOT" goroot
+	zip -q -r $ZIPFILE goroot/* # glob to ignore dotfiles (like .git)
+	rm goroot
+}
+
+makeIndexfile() {
+	echo "*** make $INDEXFILE"
+	godoc=$(go env GOPATH)/bin/godoc
+	# NOTE: run godoc without GOPATH set. Otherwise third-party packages will end up in the index.
+	GOPATH= $godoc -write_index -goroot goroot -index_files=$INDEXFILE -zip=$ZIPFILE
+}
+
+splitIndexfile() {
+	echo "*** split $INDEXFILE"
+	rm -f $SPLITFILES*
+	split -b8m $INDEXFILE $SPLITFILES
+}
+
+cd $(dirname $0)
+
+install
+getArgs "$@"
+makeZipfile
+makeIndexfile
+splitIndexfile
+rm $INDEXFILE
+
+echo "*** setup complete"
diff --git a/cmd/godoc/setup-godoc-app.bash b/cmd/godoc/setup-godoc-app.bash
deleted file mode 100755
index b50d947444a..00000000000
--- a/cmd/godoc/setup-godoc-app.bash
+++ /dev/null
@@ -1,134 +0,0 @@
-#!/usr/bin/env bash
-
-# Copyright 2011 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 script creates a complete godoc app in $APPDIR.
-# It copies the cmd/godoc and src/go/... sources from GOROOT,
-# synthesizes an app.yaml file, and creates the .zip, index, and
-# configuration files.
-#
-# If an argument is provided it is assumed to be the app-engine godoc directory.
-# Without an argument, $APPDIR is used instead. If GOROOT is not set, "go env"
-# is consulted to find the $GOROOT.
-#
-# The script creates a .zip file representing the $GOROOT file system
-# and computes the corresponding search index files. These files are then
-# copied to $APPDIR. A corresponding godoc configuration file is created
-# in $APPDIR/appconfig.go.
-
-ZIPFILE=godoc.zip
-INDEXFILE=godoc.index
-SPLITFILES=index.split.
-GODOC=golang.org/x/tools/cmd/godoc
-CONFIGFILE=$GODOC/appconfig.go
-
-error() {
-	echo "error: $1"
-	exit 2
-}
-
-getArgs() {
-	if [ -z $APPENGINE_SDK ]; then
-		error "APPENGINE_SDK environment variable not set"
-	fi
-	if [ ! -x $APPENGINE_SDK/goapp ]; then
-		error "couldn't find goapp command in $APPENGINE_SDK"
-	fi
-	if [ -z $GOROOT ]; then
-		GOROOT=$(go env GOROOT)
-		echo "GOROOT not set explicitly, using go env value instead"
-	fi
-	if [ -z $APPDIR ]; then
-		if [ $# == 0 ]; then
-			error "APPDIR not set, and no argument provided"
-		fi
-		APPDIR=$1
-		echo "APPDIR not set, using argument instead"
-	fi
-
-	# safety checks
-	if [ ! -d $GOROOT ]; then
-		error "$GOROOT is not a directory"
-	fi
-	if [ -e $APPDIR ]; then
-		error "$APPDIR exists; check and remove it before trying again"
-	fi
-
-	# reporting
-	echo "GOROOT = $GOROOT"
-	echo "APPDIR = $APPDIR"
-}
-
-fetchGodoc() {
-	echo "*** Fetching godoc (if not already in GOPATH)"
-	unset GOBIN
-	go=$APPENGINE_SDK/goapp
-	$go get -d -tags appengine $GODOC
-	mkdir -p $APPDIR/$GODOC
-	cp $(find $($go list -f '{{.Dir}}' $GODOC) -mindepth 1 -maxdepth 1 -type f) $APPDIR/$GODOC/
-}
-
-makeAppYaml() {
-	echo "*** make $APPDIR/app.yaml"
-	cat > $APPDIR/app.yaml <<EOF
-application: godoc
-version: 1
-runtime: go
-api_version: go1
-
-handlers:
-- url: /.*
-  script: _go_app
-EOF
-}
-
-makeZipfile() {
-	echo "*** make $APPDIR/$ZIPFILE"
-	zip -q -r $APPDIR/$ZIPFILE $GOROOT/*
-}
-
-makeIndexfile() {
-	echo "*** make $APPDIR/$INDEXFILE"
-	GOPATH= godoc -write_index -index_files=$APPDIR/$INDEXFILE -zip=$APPDIR/$ZIPFILE
-}
-
-splitIndexfile() {
-	echo "*** split $APPDIR/$INDEXFILE"
-	split -b8m $APPDIR/$INDEXFILE $APPDIR/$SPLITFILES
-}
-
-makeConfigfile() {
-	echo "*** make $APPDIR/$CONFIGFILE"
-	cat > $APPDIR/$CONFIGFILE <<EOF
-package main
-
-// GENERATED FILE - DO NOT MODIFY BY HAND.
-// (generated by golang.org/x/tools/cmd/godoc/setup-godoc-app.bash)
-
-const (
-	// .zip filename
-	zipFilename = "$ZIPFILE"
-
-	// goroot directory in .zip file
-	zipGoroot = "$GOROOT"
-
-	// glob pattern describing search index files
-	// (if empty, the index is built at run-time)
-	indexFilenames = "$SPLITFILES*"
-)
-EOF
-}
-
-getArgs "$@"
-set -e
-mkdir $APPDIR
-fetchGodoc
-makeAppYaml
-makeZipfile
-makeIndexfile
-splitIndexfile
-makeConfigfile
-
-echo "*** setup complete"