diff --git a/app/appengine/README.md b/app/appengine/README.md
new file mode 100644
index 00000000..388093f5
--- /dev/null
+++ b/app/appengine/README.md
@@ -0,0 +1,11 @@
+# build.golang.org App Engine App
+
+Update with
+
+```sh
+gcloud config set project golang-org
+gcloud app deploy --no-promote -v {build|build-test} app.yaml
+```
+
+Using -v build will run as build.golang.org.
+Using -v build-test will run as build-test.golang.org.
diff --git a/app/app.yaml b/app/appengine/app.yaml
similarity index 69%
rename from app/app.yaml
rename to app/appengine/app.yaml
index 8381786b..915e1fee 100644
--- a/app/app.yaml
+++ b/app/appengine/app.yaml
@@ -1,12 +1,5 @@
-# Update with
-#	google_appengine/appcfg.py [-V build-test] update .
-#
-# Using -V build-test will run as build-test.golang.org.
-
-application: golang-org
-version: build
 runtime: go
-api_version: go1
+api_version: go1.8
 
 handlers:
 - url: /static
diff --git a/app/build/build.go b/app/appengine/build.go
similarity index 92%
rename from app/build/build.go
rename to app/appengine/build.go
index 5861f15a..5f90719b 100644
--- a/app/build/build.go
+++ b/app/appengine/build.go
@@ -9,6 +9,7 @@ package build
 import (
 	"bytes"
 	"compress/gzip"
+	"context"
 	"errors"
 	"fmt"
 	"io"
@@ -19,10 +20,9 @@ import (
 	"strings"
 	"time"
 
-	"appengine"
-	"appengine/datastore"
+	"google.golang.org/appengine/datastore"
 
-	"cache"
+	"golang.org/x/build/app/cache"
 
 	"golang.org/x/build/internal/loghash"
 )
@@ -44,7 +44,7 @@ func (p *Package) String() string {
 	return fmt.Sprintf("%s: %q", p.Path, p.Name)
 }
 
-func (p *Package) Key(c appengine.Context) *datastore.Key {
+func (p *Package) Key(c context.Context) *datastore.Key {
 	key := p.Path
 	if key == "" {
 		key = "go"
@@ -53,7 +53,7 @@ func (p *Package) Key(c appengine.Context) *datastore.Key {
 }
 
 // LastCommit returns the most recent Commit for this Package.
-func (p *Package) LastCommit(c appengine.Context) (*Commit, error) {
+func (p *Package) LastCommit(c context.Context) (*Commit, error) {
 	var commits []*Commit
 	_, err := datastore.NewQuery("Commit").
 		Ancestor(p.Key(c)).
@@ -70,7 +70,7 @@ func (p *Package) LastCommit(c appengine.Context) (*Commit, error) {
 }
 
 // GetPackage fetches a Package by path from the datastore.
-func GetPackage(c appengine.Context, path string) (*Package, error) {
+func GetPackage(c context.Context, path string) (*Package, error) {
 	p := &Package{Path: path}
 	err := datastore.Get(c, p.Key(c), p)
 	if err == datastore.ErrNoSuchEntity {
@@ -116,7 +116,7 @@ type Commit struct {
 	buildingURLs map[builderAndGoHash]string
 }
 
-func (com *Commit) Key(c appengine.Context) *datastore.Key {
+func (com *Commit) Key(c context.Context) *datastore.Key {
 	if com.Hash == "" {
 		panic("tried Key on Commit with empty Hash")
 	}
@@ -135,7 +135,7 @@ func (c *Commit) Valid() error {
 	return nil
 }
 
-func putCommit(c appengine.Context, com *Commit) error {
+func putCommit(c context.Context, com *Commit) error {
 	if err := com.Valid(); err != nil {
 		return fmt.Errorf("putting Commit: %v", err)
 	}
@@ -154,7 +154,7 @@ const maxResults = 1000
 
 // AddResult adds the denormalized Result data to the Commit's ResultData field.
 // It must be called from inside a datastore transaction.
-func (com *Commit) AddResult(c appengine.Context, r *Result) error {
+func (com *Commit) AddResult(c context.Context, r *Result) error {
 	if err := datastore.Get(c, com.Key(c), com); err != nil {
 		return fmt.Errorf("getting Commit: %v", err)
 	}
@@ -191,7 +191,7 @@ func (com *Commit) RemoveResult(r *Result) {
 
 // AddPerfResult remembers that the builder has run the benchmark on the commit.
 // It must be called from inside a datastore transaction.
-func (com *Commit) AddPerfResult(c appengine.Context, builder, benchmark string) error {
+func (com *Commit) AddPerfResult(c context.Context, builder, benchmark string) error {
 	if err := datastore.Get(c, com.Key(c), com); err != nil {
 		return fmt.Errorf("getting Commit: %v", err)
 	}
@@ -307,7 +307,7 @@ type CommitRun struct {
 	NeedsBenchmarking []bool      `datastore:",noindex"`
 }
 
-func (cr *CommitRun) Key(c appengine.Context) *datastore.Key {
+func (cr *CommitRun) Key(c context.Context) *datastore.Key {
 	p := Package{Path: cr.PackagePath}
 	key := strconv.Itoa(cr.StartCommitNum)
 	return datastore.NewKey(c, "CommitRun", key, 0, p.Key(c))
@@ -315,7 +315,7 @@ func (cr *CommitRun) Key(c appengine.Context) *datastore.Key {
 
 // GetCommitRun loads and returns CommitRun that contains information
 // for commit commitNum.
-func GetCommitRun(c appengine.Context, commitNum int) (*CommitRun, error) {
+func GetCommitRun(c context.Context, commitNum int) (*CommitRun, error) {
 	cr := &CommitRun{StartCommitNum: commitNum / PerfRunLength * PerfRunLength}
 	err := datastore.Get(c, cr.Key(c), cr)
 	if err != nil && err != datastore.ErrNoSuchEntity {
@@ -331,7 +331,7 @@ func GetCommitRun(c appengine.Context, commitNum int) (*CommitRun, error) {
 	return cr, nil
 }
 
-func (cr *CommitRun) AddCommit(c appengine.Context, com *Commit) error {
+func (cr *CommitRun) AddCommit(c context.Context, com *Commit) error {
 	if com.Num < cr.StartCommitNum || com.Num >= cr.StartCommitNum+PerfRunLength {
 		return fmt.Errorf("AddCommit: commit num %v out of range [%v, %v)",
 			com.Num, cr.StartCommitNum, cr.StartCommitNum+PerfRunLength)
@@ -353,7 +353,7 @@ func (cr *CommitRun) AddCommit(c appengine.Context, com *Commit) error {
 // GetCommits returns [startCommitNum, startCommitNum+n) commits.
 // Commits information is partial (obtained from CommitRun),
 // do not store them back into datastore.
-func GetCommits(c appengine.Context, startCommitNum, n int) ([]*Commit, error) {
+func GetCommits(c context.Context, startCommitNum, n int) ([]*Commit, error) {
 	if startCommitNum < 0 || n <= 0 {
 		return nil, fmt.Errorf("GetCommits: invalid args (%v, %v)", startCommitNum, n)
 	}
@@ -436,7 +436,7 @@ type Result struct {
 	RunTime int64 // time to build+test in nanoseconds
 }
 
-func (r *Result) Key(c appengine.Context) *datastore.Key {
+func (r *Result) Key(c context.Context) *datastore.Key {
 	p := Package{Path: r.PackagePath}
 	key := r.Builder + "|" + r.PackagePath + "|" + r.Hash + "|" + r.GoHash
 	return datastore.NewKey(c, "Result", key, 0, p.Key(c))
@@ -477,7 +477,7 @@ type ParsedPerfResult struct {
 	Artifacts map[string]string
 }
 
-func (r *PerfResult) Key(c appengine.Context) *datastore.Key {
+func (r *PerfResult) Key(c context.Context) *datastore.Key {
 	p := Package{Path: r.PackagePath}
 	key := r.CommitHash
 	return datastore.NewKey(c, "PerfResult", key, 0, p.Key(c))
@@ -561,7 +561,7 @@ type PerfMetricRun struct {
 	Vals           []int64 `datastore:",noindex"`
 }
 
-func (m *PerfMetricRun) Key(c appengine.Context) *datastore.Key {
+func (m *PerfMetricRun) Key(c context.Context) *datastore.Key {
 	p := Package{Path: m.PackagePath}
 	key := m.Builder + "|" + m.Benchmark + "|" + m.Metric + "|" + strconv.Itoa(m.StartCommitNum)
 	return datastore.NewKey(c, "PerfMetricRun", key, 0, p.Key(c))
@@ -569,7 +569,7 @@ func (m *PerfMetricRun) Key(c appengine.Context) *datastore.Key {
 
 // GetPerfMetricRun loads and returns PerfMetricRun that contains information
 // for commit commitNum.
-func GetPerfMetricRun(c appengine.Context, builder, benchmark, metric string, commitNum int) (*PerfMetricRun, error) {
+func GetPerfMetricRun(c context.Context, builder, benchmark, metric string, commitNum int) (*PerfMetricRun, error) {
 	startCommitNum := commitNum / PerfRunLength * PerfRunLength
 	m := &PerfMetricRun{Builder: builder, Benchmark: benchmark, Metric: metric, StartCommitNum: startCommitNum}
 	err := datastore.Get(c, m.Key(c), m)
@@ -582,7 +582,7 @@ func GetPerfMetricRun(c appengine.Context, builder, benchmark, metric string, co
 	return m, nil
 }
 
-func (m *PerfMetricRun) AddMetric(c appengine.Context, commitNum int, v uint64) error {
+func (m *PerfMetricRun) AddMetric(c context.Context, commitNum int, v uint64) error {
 	if commitNum < m.StartCommitNum || commitNum >= m.StartCommitNum+PerfRunLength {
 		return fmt.Errorf("AddMetric: CommitNum %v out of range [%v, %v)",
 			commitNum, m.StartCommitNum, m.StartCommitNum+PerfRunLength)
@@ -596,7 +596,7 @@ func (m *PerfMetricRun) AddMetric(c appengine.Context, commitNum int, v uint64)
 
 // GetPerfMetricsForCommits returns perf metrics for builder/benchmark/metric
 // and commits [startCommitNum, startCommitNum+n).
-func GetPerfMetricsForCommits(c appengine.Context, builder, benchmark, metric string, startCommitNum, n int) ([]uint64, error) {
+func GetPerfMetricsForCommits(c context.Context, builder, benchmark, metric string, startCommitNum, n int) ([]uint64, error) {
 	if startCommitNum < 0 || n <= 0 {
 		return nil, fmt.Errorf("GetPerfMetricsForCommits: invalid args (%v, %v)", startCommitNum, n)
 	}
@@ -657,14 +657,14 @@ type PerfConfig struct {
 	noise map[string]float64
 }
 
-func PerfConfigKey(c appengine.Context) *datastore.Key {
+func PerfConfigKey(c context.Context) *datastore.Key {
 	p := Package{}
 	return datastore.NewKey(c, "PerfConfig", "PerfConfig", 0, p.Key(c))
 }
 
 const perfConfigCacheKey = "perf-config"
 
-func GetPerfConfig(c appengine.Context, r *http.Request) (*PerfConfig, error) {
+func GetPerfConfig(c context.Context, r *http.Request) (*PerfConfig, error) {
 	pc := new(PerfConfig)
 	now := cache.Now(c)
 	if cache.Get(c, r, now, perfConfigCacheKey, pc) {
@@ -703,7 +703,7 @@ func (pc *PerfConfig) NoiseLevel(builder, benchmark, metric string) float64 {
 
 // UpdatePerfConfig updates the PerfConfig entity with results of benchmarking.
 // Returns whether it's a benchmark that we have not yet seem on the builder.
-func UpdatePerfConfig(c appengine.Context, r *http.Request, req *PerfRequest) (newBenchmark bool, err error) {
+func UpdatePerfConfig(c context.Context, r *http.Request, req *PerfRequest) (newBenchmark bool, err error) {
 	pc, err := GetPerfConfig(c, r)
 	if err != nil {
 		return false, err
@@ -820,14 +820,14 @@ type PerfTodo struct {
 	CommitNums  []int `datastore:",noindex"` // LIFO queue of commits to benchmark.
 }
 
-func (todo *PerfTodo) Key(c appengine.Context) *datastore.Key {
+func (todo *PerfTodo) Key(c context.Context) *datastore.Key {
 	p := Package{Path: todo.PackagePath}
 	key := todo.Builder
 	return datastore.NewKey(c, "PerfTodo", key, 0, p.Key(c))
 }
 
 // AddCommitToPerfTodo adds the commit to all existing PerfTodo entities.
-func AddCommitToPerfTodo(c appengine.Context, com *Commit) error {
+func AddCommitToPerfTodo(c context.Context, com *Commit) error {
 	var todos []*PerfTodo
 	_, err := datastore.NewQuery("PerfTodo").
 		Ancestor((&Package{}).Key(c)).
@@ -863,7 +863,7 @@ func (l *Log) Text() ([]byte, error) {
 	return b, nil
 }
 
-func PutLog(c appengine.Context, text string) (hash string, err error) {
+func PutLog(c context.Context, text string) (hash string, err error) {
 	b := new(bytes.Buffer)
 	z, _ := gzip.NewWriterLevel(b, gzip.BestCompression)
 	io.WriteString(z, text)
@@ -889,7 +889,7 @@ func (t *Tag) String() string {
 	return t.Name
 }
 
-func (t *Tag) Key(c appengine.Context) *datastore.Key {
+func (t *Tag) Key(c context.Context) *datastore.Key {
 	p := &Package{}
 	s := t.Kind
 	if t.Kind == "release" {
@@ -912,14 +912,14 @@ func (t *Tag) Valid() error {
 }
 
 // Commit returns the Commit that corresponds with this Tag.
-func (t *Tag) Commit(c appengine.Context) (*Commit, error) {
+func (t *Tag) Commit(c context.Context) (*Commit, error) {
 	com := &Commit{Hash: t.Hash}
 	err := datastore.Get(c, com.Key(c), com)
 	return com, err
 }
 
 // GetTag fetches a Tag by name from the datastore.
-func GetTag(c appengine.Context, kind, name string) (*Tag, error) {
+func GetTag(c context.Context, kind, name string) (*Tag, error) {
 	t := &Tag{Kind: kind, Name: name}
 	if err := datastore.Get(c, t.Key(c), t); err != nil {
 		return nil, err
@@ -932,7 +932,7 @@ func GetTag(c appengine.Context, kind, name string) (*Tag, error) {
 
 // Packages returns packages of the specified kind.
 // Kind must be one of "external" or "subrepo".
-func Packages(c appengine.Context, kind string) ([]*Package, error) {
+func Packages(c context.Context, kind string) ([]*Package, error) {
 	switch kind {
 	case "external", "subrepo":
 	default:
diff --git a/app/build/config.go b/app/appengine/config.go
similarity index 81%
rename from app/build/config.go
rename to app/appengine/config.go
index 1b41cfa3..d32653a5 100644
--- a/app/build/config.go
+++ b/app/appengine/config.go
@@ -9,8 +9,9 @@ package build
 import (
 	"sync"
 
-	"appengine"
-	"appengine/datastore"
+	"golang.org/x/net/context"
+	"google.golang.org/appengine/datastore"
+	"google.golang.org/appengine/log"
 )
 
 // A global map of rarely-changing configuration values.
@@ -35,7 +36,7 @@ type configEntity struct {
 
 // Config returns the value for the given key
 // or the empty string if no such key exists.
-func Config(c appengine.Context, key string) string {
+func Config(c context.Context, key string) string {
 	config.RLock()
 	v, ok := config.m[key]
 	config.RUnlock()
@@ -55,7 +56,7 @@ func Config(c appengine.Context, key string) string {
 	k := datastore.NewKey(c, "Config", key, 0, nil)
 	ent := configEntity{}
 	if err := datastore.Get(c, k, &ent); err != nil {
-		c.Errorf("Get Config: %v", err)
+		log.Errorf(c, "Get Config: %v", err)
 		return ""
 	}
 	// Don't return or cache the dummy value.
@@ -69,24 +70,24 @@ func Config(c appengine.Context, key string) string {
 // initConfig is invoked by the initHandler to create an entity for each key in
 // configKeys. This makes it easy to edit the configuration values using the
 // Datastore Viewer in the App Engine dashboard.
-func initConfig(c appengine.Context) {
+func initConfig(c context.Context) {
 	for _, key := range configKeys {
-		err := datastore.RunInTransaction(c, func(c appengine.Context) error {
+		err := datastore.RunInTransaction(c, func(c context.Context) error {
 			k := datastore.NewKey(c, "Config", key, 0, nil)
 			ent := configEntity{}
 			if err := datastore.Get(c, k, &ent); err == nil {
-				c.Infof("huh? %v", key)
+				log.Infof(c, "huh? %v", key)
 				return nil
 			} else if err != datastore.ErrNoSuchEntity {
 				return err
 			}
 			ent.Value = configDummy
 			_, err := datastore.Put(c, k, &ent)
-			c.Infof("BLAH BLAH %v", key)
+			log.Infof(c, "BLAH BLAH %v", key)
 			return err
 		}, nil)
 		if err != nil {
-			c.Errorf("initConfig %v: %v", key, err)
+			log.Errorf(c, "initConfig %v: %v", key, err)
 		}
 	}
 }
diff --git a/app/cron-part.yaml b/app/appengine/cron-part.yaml
similarity index 100%
rename from app/cron-part.yaml
rename to app/appengine/cron-part.yaml
diff --git a/app/cron.sh b/app/appengine/cron.sh
similarity index 100%
rename from app/cron.sh
rename to app/appengine/cron.sh
diff --git a/app/build/dash.go b/app/appengine/dash.go
similarity index 97%
rename from app/build/dash.go
rename to app/appengine/dash.go
index c58484d5..03b18e8f 100644
--- a/app/build/dash.go
+++ b/app/appengine/dash.go
@@ -7,10 +7,11 @@
 package build
 
 import (
+	"context"
 	"net/http"
 	"strings"
 
-	"appengine"
+	"google.golang.org/appengine"
 )
 
 func handleFunc(path string, h http.HandlerFunc) {
@@ -53,7 +54,7 @@ func dashboardForRequest(r *http.Request) *Dashboard {
 
 // Context returns a namespaced context for this dashboard, or panics if it
 // fails to create a new context.
-func (d *Dashboard) Context(c appengine.Context) appengine.Context {
+func (d *Dashboard) Context(c context.Context) context.Context {
 	if d.Namespace == "" {
 		return c
 	}
diff --git a/app/build/handler.go b/app/appengine/handler.go
similarity index 94%
rename from app/build/handler.go
rename to app/appengine/handler.go
index f0b124c9..2b750518 100644
--- a/app/build/handler.go
+++ b/app/appengine/handler.go
@@ -21,12 +21,13 @@ import (
 	"time"
 	"unicode/utf8"
 
-	"appengine"
-	"appengine/datastore"
-	"appengine/memcache"
-
-	"cache"
-	"key"
+	"golang.org/x/build/app/cache"
+	"golang.org/x/build/app/key"
+	"golang.org/x/net/context"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
+	"google.golang.org/appengine/log"
+	"google.golang.org/appengine/memcache"
 )
 
 const (
@@ -108,7 +109,7 @@ func commitHandler(r *http.Request) (interface{}, error) {
 		return nil, fmt.Errorf("reading Body: %v", err)
 	}
 	if !bytes.Contains(body, needsBenchmarkingBytes) {
-		c.Warningf("old builder detected at %v", r.RemoteAddr)
+		log.Warningf(c, "old builder detected at %v", r.RemoteAddr)
 		return nil, fmt.Errorf("rejecting old builder request, body does not contain %s: %q", needsBenchmarkingBytes, body)
 	}
 	if err := json.Unmarshal(body, com); err != nil {
@@ -119,7 +120,7 @@ func commitHandler(r *http.Request) (interface{}, error) {
 		return nil, fmt.Errorf("validating Commit: %v", err)
 	}
 	defer cache.Tick(c)
-	tx := func(c appengine.Context) error {
+	tx := func(c context.Context) error {
 		return addCommit(c, com)
 	}
 	return nil, datastore.RunInTransaction(c, tx, nil)
@@ -129,7 +130,7 @@ var needsBenchmarkingBytes = []byte(`"NeedsBenchmarking"`)
 
 // addCommit adds the Commit entity to the datastore and updates the tip Tag.
 // It must be run inside a datastore transaction.
-func addCommit(c appengine.Context, com *Commit) error {
+func addCommit(c context.Context, com *Commit) error {
 	var ec Commit // existing commit
 	isUpdate := false
 	err := datastore.Get(c, com.Key(c), &ec)
@@ -335,7 +336,7 @@ func todoHandler(r *http.Request) (interface{}, error) {
 // If provided with non-empty packagePath and goHash args, it scans the first
 // 20 Commits in Num-descending order for the specified packagePath and
 // returns the first that doesn't have a Result for this builder and goHash.
-func buildTodo(c appengine.Context, builder, packagePath, goHash string) (*Commit, error) {
+func buildTodo(c context.Context, builder, packagePath, goHash string) (*Commit, error) {
 	p, err := GetPackage(c, packagePath)
 	if err != nil {
 		return nil, err
@@ -390,7 +391,7 @@ func buildTodo(c appengine.Context, builder, packagePath, goHash string) (*Commi
 	for _, pkg := range pkgs {
 		com, err := pkg.LastCommit(c)
 		if err != nil {
-			c.Warningf("%v: no Commit found: %v", pkg, err)
+			log.Warningf(c, "%v: no Commit found: %v", pkg, err)
 			continue
 		}
 		if com.Result(builder, tag.Hash) == nil {
@@ -402,7 +403,7 @@ func buildTodo(c appengine.Context, builder, packagePath, goHash string) (*Commi
 }
 
 // perfTodo returns the next Commit to be benchmarked (or nil if none available).
-func perfTodo(c appengine.Context, builder string) (*Commit, error) {
+func perfTodo(c context.Context, builder string) (*Commit, error) {
 	p := &Package{}
 	todo := &PerfTodo{Builder: builder}
 	err := datastore.Get(c, todo.Key(c), todo)
@@ -448,9 +449,9 @@ func perfTodo(c appengine.Context, builder string) (*Commit, error) {
 }
 
 // buildPerfTodo creates PerfTodo for the builder with all commits. In a transaction.
-func buildPerfTodo(c appengine.Context, builder string) (*PerfTodo, error) {
+func buildPerfTodo(c context.Context, builder string) (*PerfTodo, error) {
 	todo := &PerfTodo{Builder: builder}
-	tx := func(c appengine.Context) error {
+	tx := func(c context.Context) error {
 		err := datastore.Get(c, todo.Key(c), todo)
 		if err != nil && err != datastore.ErrNoSuchEntity {
 			return fmt.Errorf("fetching PerfTodo: %v", err)
@@ -499,7 +500,7 @@ func buildPerfTodo(c appengine.Context, builder string) (*PerfTodo, error) {
 	return todo, datastore.RunInTransaction(c, tx, nil)
 }
 
-func removeCommitFromPerfTodo(c appengine.Context, builder string, num int) error {
+func removeCommitFromPerfTodo(c context.Context, builder string, num int) error {
 	todo := &PerfTodo{Builder: builder}
 	err := datastore.Get(c, todo.Key(c), todo)
 	if err != nil && err != datastore.ErrNoSuchEntity {
@@ -604,7 +605,7 @@ func resultHandler(r *http.Request) (interface{}, error) {
 		}
 		res.LogHash = hash
 	}
-	tx := func(c appengine.Context) error {
+	tx := func(c context.Context) error {
 		// check Package exists
 		if _, err := GetPackage(c, res.PackagePath); err != nil {
 			return fmt.Errorf("GetPackage: %v", err)
@@ -669,7 +670,7 @@ func perfResultHandler(r *http.Request) (interface{}, error) {
 		}
 		req.Artifacts[i].Body = hash
 	}
-	tx := func(c appengine.Context) error {
+	tx := func(c context.Context) error {
 		return addPerfResult(c, r, req)
 	}
 	return nil, datastore.RunInTransaction(c, tx, nil)
@@ -678,7 +679,7 @@ func perfResultHandler(r *http.Request) (interface{}, error) {
 // addPerfResult creates PerfResult and updates Commit, PerfTodo,
 // PerfMetricRun and PerfConfig.
 // MUST be called from inside a transaction.
-func addPerfResult(c appengine.Context, r *http.Request, req *PerfRequest) error {
+func addPerfResult(c context.Context, r *http.Request, req *PerfRequest) error {
 	// check Package exists
 	p, err := GetPackage(c, "")
 	if err != nil {
@@ -745,7 +746,7 @@ func addPerfResult(c appengine.Context, r *http.Request, req *PerfRequest) error
 }
 
 // MUST be called from inside a transaction.
-func checkPerfChanges(c appengine.Context, r *http.Request, com *Commit, builder string, res *PerfResult) error {
+func checkPerfChanges(c context.Context, r *http.Request, com *Commit, builder string, res *PerfResult) error {
 	pc, err := GetPerfConfig(c, r)
 	if err != nil {
 		return err
@@ -811,7 +812,7 @@ func checkPerfChanges(c appengine.Context, r *http.Request, com *Commit, builder
 	return nil
 }
 
-func comparePerfResults(c appengine.Context, pc *PerfConfig, builder string, prevRes, res *PerfResult) error {
+func comparePerfResults(c context.Context, pc *PerfConfig, builder string, prevRes, res *PerfResult) error {
 	changes := significantPerfChanges(pc, builder, prevRes, res)
 	if len(changes) == 0 {
 		return nil
@@ -869,7 +870,7 @@ func clearResultsHandler(r *http.Request) (interface{}, error) {
 	c := contextForRequest(r)
 	defer cache.Tick(c)
 	pkg := (&Package{}).Key(c) // TODO(adg): support clearing sub-repos
-	err := datastore.RunInTransaction(c, func(c appengine.Context) error {
+	err := datastore.RunInTransaction(c, func(c context.Context) error {
 		var coms []*Commit
 		keys, err := datastore.NewQuery("Commit").
 			Ancestor(pkg).
@@ -958,12 +959,12 @@ func AuthHandler(h dashHandler) http.HandlerFunc {
 		// Write JSON response.
 		dashResp := &dashResponse{Response: resp}
 		if err != nil {
-			c.Errorf("%v", err)
+			log.Errorf(c, "%v", err)
 			dashResp.Error = err.Error()
 		}
 		w.Header().Set("Content-Type", "application/json")
 		if err = json.NewEncoder(w).Encode(dashResp); err != nil {
-			c.Criticalf("encoding response: %v", err)
+			log.Criticalf(c, "encoding response: %v", err)
 		}
 	}
 }
@@ -1002,7 +1003,7 @@ func validHash(hash string) bool {
 	return hash != ""
 }
 
-func validKey(c appengine.Context, key, builder string) bool {
+func validKey(c context.Context, key, builder string) bool {
 	if isMasterKey(c, key) {
 		return true
 	}
@@ -1012,23 +1013,24 @@ func validKey(c appengine.Context, key, builder string) bool {
 	return key == builderKey(c, builder)
 }
 
-func isMasterKey(c appengine.Context, k string) bool {
+func isMasterKey(c context.Context, k string) bool {
 	return appengine.IsDevAppServer() || k == key.Secret(c)
 }
 
-func builderKey(c appengine.Context, builder string) string {
+func builderKey(c context.Context, builder string) string {
 	h := hmac.New(md5.New, []byte(key.Secret(c)))
 	h.Write([]byte(builder))
 	return fmt.Sprintf("%x", h.Sum(nil))
 }
 
 func logErr(w http.ResponseWriter, r *http.Request, err error) {
-	contextForRequest(r).Errorf("Error: %v", err)
+	c := contextForRequest(r)
+	log.Errorf(c, "Error: %v", err)
 	w.WriteHeader(http.StatusInternalServerError)
 	fmt.Fprint(w, "Error: ", html.EscapeString(err.Error()))
 }
 
-func contextForRequest(r *http.Request) appengine.Context {
+func contextForRequest(r *http.Request) context.Context {
 	return dashboardForRequest(r).Context(appengine.NewContext(r))
 }
 
diff --git a/app/index.yaml b/app/appengine/index.yaml
similarity index 100%
rename from app/index.yaml
rename to app/appengine/index.yaml
diff --git a/app/build/init.go b/app/appengine/init.go
similarity index 91%
rename from app/build/init.go
rename to app/appengine/init.go
index d796c94c..592eafec 100644
--- a/app/build/init.go
+++ b/app/appengine/init.go
@@ -10,11 +10,11 @@ import (
 	"fmt"
 	"net/http"
 
-	"appengine"
-	"appengine/datastore"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
 
-	"cache"
-	"key"
+	"golang.org/x/build/app/cache"
+	"golang.org/x/build/app/key"
 )
 
 func initHandler(w http.ResponseWriter, r *http.Request) {
diff --git a/app/build/notify.go b/app/appengine/notify.go
similarity index 84%
rename from app/build/notify.go
rename to app/appengine/notify.go
index 6fb9536e..a9997803 100644
--- a/app/build/notify.go
+++ b/app/appengine/notify.go
@@ -8,6 +8,7 @@ package build
 
 import (
 	"bytes"
+	"context"
 	"encoding/gob"
 	"encoding/json"
 	"fmt"
@@ -18,10 +19,11 @@ import (
 	"strings"
 	"text/template"
 
-	"appengine"
-	"appengine/datastore"
-	"appengine/delay"
-	"appengine/urlfetch"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
+	"google.golang.org/appengine/delay"
+	"google.golang.org/appengine/log"
+	"google.golang.org/appengine/urlfetch"
 )
 
 const (
@@ -50,7 +52,7 @@ var ignoreFailure = map[string]bool{
 //
 // This must be run in a datastore transaction, and the provided *Commit must
 // have been retrieved from the datastore within that transaction.
-func notifyOnFailure(c appengine.Context, com *Commit, builder string) error {
+func notifyOnFailure(c context.Context, com *Commit, builder string) error {
 	if ignoreFailure[builder] {
 		return nil
 	}
@@ -79,8 +81,8 @@ func notifyOnFailure(c appengine.Context, com *Commit, builder string) error {
 			return err
 		}
 		if nr := next.Result(builder, ""); nr != nil && !nr.OK {
-			c.Debugf("commit ok: %#v\nresult: %#v", com, cr)
-			c.Debugf("next commit broken: %#v\nnext result:%#v", next, nr)
+			log.Debugf(c, "commit ok: %#v\nresult: %#v", com, cr)
+			log.Debugf(c, "next commit broken: %#v\nnext result:%#v", next, nr)
 			broken = next
 		}
 	} else {
@@ -96,8 +98,8 @@ func notifyOnFailure(c appengine.Context, com *Commit, builder string) error {
 			return err
 		}
 		if pr := prev.Result(builder, ""); pr != nil && pr.OK {
-			c.Debugf("commit broken: %#v\nresult: %#v", com, cr)
-			c.Debugf("previous commit ok: %#v\nprevious result:%#v", prev, pr)
+			log.Debugf(c, "commit broken: %#v\nresult: %#v", com, cr)
+			log.Debugf(c, "previous commit ok: %#v\nprevious result:%#v", prev, pr)
 			broken = com
 		}
 	}
@@ -112,7 +114,7 @@ func notifyOnFailure(c appengine.Context, com *Commit, builder string) error {
 }
 
 // firstMatch executes the query q and loads the first entity into v.
-func firstMatch(c appengine.Context, q *datastore.Query, v interface{}) error {
+func firstMatch(c context.Context, q *datastore.Query, v interface{}) error {
 	t := q.Limit(1).Run(c)
 	_, err := t.Next(v)
 	if err == datastore.Done {
@@ -124,12 +126,12 @@ func firstMatch(c appengine.Context, q *datastore.Query, v interface{}) error {
 var (
 	notifyLater = delay.Func("notify", notify)
 	notifyTmpl  = template.Must(template.New("notify.txt").
-			Funcs(template.FuncMap(tmplFuncs)).ParseFiles("build/notify.txt"))
+			Funcs(template.FuncMap(tmplFuncs)).ParseFiles("notify.txt"))
 )
 
 // notify tries to update the CL for the given Commit with a failure message.
 // If it doesn't succeed, it sends a failure email to golang-dev.
-func notify(c appengine.Context, com *Commit, builder, logHash string) {
+func notify(c context.Context, com *Commit, builder, logHash string) {
 	var msg bytes.Buffer
 	err := notifyTmpl.Execute(&msg, struct {
 		Builder  string
@@ -137,19 +139,19 @@ func notify(c appengine.Context, com *Commit, builder, logHash string) {
 		Hostname string
 	}{builder, logHash, domain})
 	if err != nil {
-		c.Criticalf("couldn't render template: %v", err)
+		log.Criticalf(c, "couldn't render template: %v", err)
 		return
 	}
 	if err := postGerritMessage(c, com, msg.String()); err != nil {
-		c.Errorf("couldn't post to gerrit: %v", err)
+		log.Errorf(c, "couldn't post to gerrit: %v", err)
 	}
 }
 
 // postGerritMessage posts a message to the code review thread for the given
 // Commit.
-func postGerritMessage(c appengine.Context, com *Commit, message string) error {
+func postGerritMessage(c context.Context, com *Commit, message string) error {
 	if appengine.IsDevAppServer() {
-		c.Infof("Skiping update of Gerrit review for %v with message: %v", com, message)
+		log.Infof(c, "Skiping update of Gerrit review for %v with message: %v", com, message)
 		return nil
 	}
 	// Get change ID using commit hash.
@@ -203,7 +205,7 @@ func init() {
 }
 
 // MUST be called from inside a transaction.
-func sendPerfFailMail(c appengine.Context, builder string, res *PerfResult) error {
+func sendPerfFailMail(c context.Context, builder string, res *PerfResult) error {
 	com := &Commit{Hash: res.CommitHash}
 	if err := datastore.Get(c, com.Key(c), com); err != nil {
 		return err
@@ -224,18 +226,18 @@ func sendPerfFailMail(c appengine.Context, builder string, res *PerfResult) erro
 
 // commonNotify MUST!!! be called from within a transaction inside which
 // the provided Commit entity was retrieved from the datastore.
-func commonNotify(c appengine.Context, com *Commit, builder, logHash string) error {
+func commonNotify(c context.Context, com *Commit, builder, logHash string) error {
 	if com.Num == 0 || com.Desc == "" {
 		stk := make([]byte, 10000)
 		n := runtime.Stack(stk, false)
 		stk = stk[:n]
-		c.Errorf("refusing to notify with com=%+v\n%s", *com, string(stk))
+		log.Errorf(c, "refusing to notify with com=%+v\n%s", *com, string(stk))
 		return fmt.Errorf("misuse of commonNotify")
 	}
 	if com.FailNotificationSent {
 		return nil
 	}
-	c.Infof("%s is broken commit; notifying", com.Hash)
+	log.Infof(c, "%s is broken commit; notifying", com.Hash)
 	notifyLater.Call(c, com, builder, logHash) // add task to queue
 	com.FailNotificationSent = true
 	return putCommit(c, com)
@@ -277,11 +279,11 @@ var (
 	sendPerfMailTmpl  = template.Must(
 		template.New("perf_notify.txt").
 			Funcs(template.FuncMap(tmplFuncs)).
-			ParseFiles("build/perf_notify.txt"),
+			ParseFiles("perf_notify.txt"),
 	)
 )
 
-func sendPerfMailFunc(c appengine.Context, com *Commit, prevCommitHash, builder string, changes []*PerfChange) {
+func sendPerfMailFunc(c context.Context, com *Commit, prevCommitHash, builder string, changes []*PerfChange) {
 	// Sort the changes into the right order.
 	var benchmarks []*PerfChangeBenchmark
 	for _, ch := range changes {
@@ -312,11 +314,11 @@ func sendPerfMailFunc(c appengine.Context, com *Commit, prevCommitHash, builder
 		"Builder": builder, "Hostname": domain, "Url": u, "Benchmarks": benchmarks,
 	})
 	if err != nil {
-		c.Errorf("rendering perf mail template: %v", err)
+		log.Errorf(c, "rendering perf mail template: %v", err)
 		return
 	}
 
 	if err := postGerritMessage(c, com, body.String()); err != nil {
-		c.Errorf("posting to gerrit: %v", err)
+		log.Errorf(c, "posting to gerrit: %v", err)
 	}
 }
diff --git a/app/build/notify.txt b/app/appengine/notify.txt
similarity index 100%
rename from app/build/notify.txt
rename to app/appengine/notify.txt
diff --git a/app/build/perf.go b/app/appengine/perf.go
similarity index 96%
rename from app/build/perf.go
rename to app/appengine/perf.go
index a8e542f7..6a6a5cde 100644
--- a/app/build/perf.go
+++ b/app/appengine/perf.go
@@ -7,13 +7,14 @@
 package build
 
 import (
+	"context"
 	"fmt"
 	"sort"
 	"strconv"
 	"strings"
 
-	"appengine"
-	"appengine/datastore"
+	"google.golang.org/appengine/datastore"
+	"google.golang.org/appengine/log"
 )
 
 var knownTags = map[string]string{
@@ -32,7 +33,7 @@ func splitBench(benchProcs string) (string, int) {
 	return ss[0], procs
 }
 
-func dashPerfCommits(c appengine.Context, page int) ([]*Commit, error) {
+func dashPerfCommits(c context.Context, page int) ([]*Commit, error) {
 	q := datastore.NewQuery("Commit").
 		Ancestor((&Package{}).Key(c)).
 		Order("-Num").
@@ -76,13 +77,13 @@ func isPerfFailed(res *PerfResult, builder string) bool {
 // without lots of duplicate accesses to datastore.
 // It allows to iterate over newer or older results for some base commit.
 type PerfResultCache struct {
-	c       appengine.Context
+	c       context.Context
 	newer   bool
 	iter    *datastore.Iterator
 	results map[int]*PerfResult
 }
 
-func MakePerfResultCache(c appengine.Context, com *Commit, newer bool) *PerfResultCache {
+func MakePerfResultCache(c context.Context, com *Commit, newer bool) *PerfResultCache {
 	p := &Package{}
 	q := datastore.NewQuery("PerfResult").Ancestor(p.Key(c)).Limit(100)
 	if newer {
@@ -128,7 +129,7 @@ func (rc *PerfResultCache) Next(commitNum int) (*PerfResult, error) {
 		return nil, fmt.Errorf("fetching perf results: %v", err)
 	}
 	if (rc.newer && res.CommitNum < commitNum) || (!rc.newer && res.CommitNum > commitNum) {
-		rc.c.Errorf("PerfResultCache.Next: bad commit num")
+		log.Errorf(rc.c, "PerfResultCache.Next: bad commit num")
 	}
 	rc.results[res.CommitNum] = res
 	return res, nil
diff --git a/app/build/perf_changes.go b/app/appengine/perf_changes.go
similarity index 98%
rename from app/build/perf_changes.go
rename to app/appengine/perf_changes.go
index f52f2113..d5f2e44c 100644
--- a/app/build/perf_changes.go
+++ b/app/appengine/perf_changes.go
@@ -14,8 +14,8 @@ import (
 	"sort"
 	"strconv"
 
-	"appengine"
-	"appengine/datastore"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
 )
 
 func init() {
@@ -221,7 +221,7 @@ type uiPerfConfigElem struct {
 }
 
 var perfChangesTemplate = template.Must(
-	template.New("perf_changes.html").Funcs(tmplFuncs).ParseFiles("build/perf_changes.html"),
+	template.New("perf_changes.html").Funcs(tmplFuncs).ParseFiles("perf_changes.html"),
 )
 
 type perfChangesData struct {
diff --git a/app/build/perf_changes.html b/app/appengine/perf_changes.html
similarity index 100%
rename from app/build/perf_changes.html
rename to app/appengine/perf_changes.html
diff --git a/app/build/perf_detail.go b/app/appengine/perf_detail.go
similarity index 97%
rename from app/build/perf_detail.go
rename to app/appengine/perf_detail.go
index 04d374a6..395f068d 100644
--- a/app/build/perf_detail.go
+++ b/app/appengine/perf_detail.go
@@ -15,8 +15,8 @@ import (
 	"strconv"
 	"strings"
 
-	"appengine"
-	"appengine/datastore"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
 )
 
 func init() {
@@ -215,5 +215,5 @@ func (l uiPerfDetailMetrics) Swap(i, j int)      { l[i], l[j] = l[j], l[i] }
 func (l uiPerfDetailMetrics) Less(i, j int) bool { return l[i].Name < l[j].Name }
 
 var uiPerfDetailTemplate = template.Must(
-	template.New("perf_detail.html").Funcs(tmplFuncs).ParseFiles("build/perf_detail.html"),
+	template.New("perf_detail.html").Funcs(tmplFuncs).ParseFiles("perf_detail.html"),
 )
diff --git a/app/build/perf_detail.html b/app/appengine/perf_detail.html
similarity index 100%
rename from app/build/perf_detail.html
rename to app/appengine/perf_detail.html
diff --git a/app/build/perf_graph.go b/app/appengine/perf_graph.go
similarity index 98%
rename from app/build/perf_graph.go
rename to app/appengine/perf_graph.go
index fbdff89d..9566ea1c 100644
--- a/app/build/perf_graph.go
+++ b/app/appengine/perf_graph.go
@@ -13,8 +13,8 @@ import (
 	"net/http"
 	"strconv"
 
-	"appengine"
-	"appengine/datastore"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
 )
 
 func init() {
@@ -244,7 +244,7 @@ func perfGraphHandler(w http.ResponseWriter, r *http.Request) {
 }
 
 var perfGraphTemplate = template.Must(
-	template.New("perf_graph.html").ParseFiles("build/perf_graph.html"),
+	template.New("perf_graph.html").ParseFiles("perf_graph.html"),
 )
 
 type perfGraphData struct {
diff --git a/app/build/perf_graph.html b/app/appengine/perf_graph.html
similarity index 100%
rename from app/build/perf_graph.html
rename to app/appengine/perf_graph.html
diff --git a/app/build/perf_learn.go b/app/appengine/perf_learn.go
similarity index 94%
rename from app/build/perf_learn.go
rename to app/appengine/perf_learn.go
index d2a57bf6..0321c5cf 100644
--- a/app/build/perf_learn.go
+++ b/app/appengine/perf_learn.go
@@ -13,8 +13,9 @@ import (
 	"net/http"
 	"sort"
 
-	"appengine"
-	"appengine/datastore"
+	"golang.org/x/net/context"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
 )
 
 func init() {
@@ -135,7 +136,7 @@ func perfLearnHandler(w http.ResponseWriter, r *http.Request) {
 		for k, v := range noise {
 			noiseLevels = append(noiseLevels, k+v)
 		}
-		tx := func(c appengine.Context) error {
+		tx := func(c context.Context) error {
 			pc, err := GetPerfConfig(c, r)
 			if err != nil {
 				return err
@@ -162,7 +163,7 @@ func perfLearnHandler(w http.ResponseWriter, r *http.Request) {
 }
 
 var perfLearnTemplate = template.Must(
-	template.New("perf_learn.html").Funcs(tmplFuncs).ParseFiles("build/perf_learn.html"),
+	template.New("perf_learn.html").Funcs(tmplFuncs).ParseFiles("perf_learn.html"),
 )
 
 type perfLearnData struct {
diff --git a/app/build/perf_learn.html b/app/appengine/perf_learn.html
similarity index 100%
rename from app/build/perf_learn.html
rename to app/appengine/perf_learn.html
diff --git a/app/build/perf_notify.txt b/app/appengine/perf_notify.txt
similarity index 100%
rename from app/build/perf_notify.txt
rename to app/appengine/perf_notify.txt
diff --git a/app/static/status_alert.gif b/app/appengine/static/status_alert.gif
similarity index 100%
rename from app/static/status_alert.gif
rename to app/appengine/static/status_alert.gif
diff --git a/app/static/status_good.gif b/app/appengine/static/status_good.gif
similarity index 100%
rename from app/static/status_good.gif
rename to app/appengine/static/status_good.gif
diff --git a/app/static/style.css b/app/appengine/static/style.css
similarity index 100%
rename from app/static/style.css
rename to app/appengine/static/style.css
diff --git a/app/build/test.go b/app/appengine/test.go
similarity index 98%
rename from app/build/test.go
rename to app/appengine/test.go
index d3dba154..fbc8d4da 100644
--- a/app/build/test.go
+++ b/app/appengine/test.go
@@ -11,6 +11,7 @@ package build
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -21,8 +22,9 @@ import (
 	"strings"
 	"time"
 
-	"appengine"
-	"appengine/datastore"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
+	"google.golang.org/appengine/log"
 )
 
 func init() {
@@ -243,7 +245,7 @@ func testHandler(w http.ResponseWriter, r *http.Request) {
 		*r = origReq
 	}()
 	for i, t := range testRequests {
-		c.Infof("running test %d %s vals='%q' req='%q' res='%q'", i, t.path, t.vals, t.req, t.res)
+		log.Infof(c, "running test %d %s vals='%q' req='%q' res='%q'", i, t.path, t.vals, t.req, t.res)
 		errorf := func(format string, args ...interface{}) {
 			fmt.Fprintf(w, "%d %s: ", i, t.path)
 			fmt.Fprintf(w, format, args...)
@@ -280,7 +282,7 @@ func testHandler(w http.ResponseWriter, r *http.Request) {
 			errorf(rec.Body.String())
 			return
 		}
-		c.Infof("response='%v'", rec.Body.String())
+		log.Infof(c, "response='%v'", rec.Body.String())
 		resp := new(dashResponse)
 
 		// If we're expecting a *Todo value,
@@ -356,7 +358,7 @@ func testHandler(w http.ResponseWriter, r *http.Request) {
 	fmt.Fprint(w, "PASS\nYou should see only one mail notification (for 0003/linux-386) in the dev_appserver logs.")
 }
 
-func nukeEntities(c appengine.Context, kinds []string) error {
+func nukeEntities(c context.Context, kinds []string) error {
 	if !appengine.IsDevAppServer() {
 		return errors.New("can't nuke production data")
 	}
diff --git a/app/build/ui.go b/app/appengine/ui.go
similarity index 94%
rename from app/build/ui.go
rename to app/appengine/ui.go
index 1b369fcc..495158cf 100644
--- a/app/build/ui.go
+++ b/app/appengine/ui.go
@@ -11,6 +11,7 @@ package build
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
 	"fmt"
 	"html/template"
@@ -22,11 +23,12 @@ import (
 
 	"golang.org/x/build/types"
 
-	"cache"
+	"golang.org/x/build/app/cache"
 
-	"appengine"
-	"appengine/datastore"
-	"appengine/memcache"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
+	"google.golang.org/appengine/log"
+	"google.golang.org/appengine/memcache"
 )
 
 func init() {
@@ -174,11 +176,11 @@ func uiHandler(w http.ResponseWriter, r *http.Request) {
 	buf.WriteTo(w)
 }
 
-func listBranches(c appengine.Context) (branches []string) {
+func listBranches(c context.Context) (branches []string) {
 	var commits []*Commit
 	_, err := datastore.NewQuery("Commit").Distinct().Project("Branch").GetAll(c, &commits)
 	if err != nil {
-		c.Errorf("listBranches: %v", err)
+		log.Errorf(c, "listBranches: %v", err)
 		return
 	}
 	for _, c := range commits {
@@ -279,7 +281,7 @@ type Pagination struct {
 
 // dashCommits gets a slice of the latest Commits to the current dashboard.
 // If page > 0 it paginates by commitsPerPage.
-func dashCommits(c appengine.Context, pkg *Package, page int, branch string) ([]*Commit, error) {
+func dashCommits(c context.Context, pkg *Package, page int, branch string) ([]*Commit, error) {
 	offset := page * commitsPerPage
 	q := datastore.NewQuery("Commit").
 		Ancestor(pkg.Key(c)).
@@ -296,7 +298,7 @@ func dashCommits(c appengine.Context, pkg *Package, page int, branch string) ([]
 }
 
 // fetchCommits gets a slice of the specific commit hashes
-func fetchCommits(c appengine.Context, pkg *Package, hashes []string) ([]*Commit, error) {
+func fetchCommits(c context.Context, pkg *Package, hashes []string) ([]*Commit, error) {
 	var out []*Commit
 	var keys []*datastore.Key
 	for _, hash := range hashes {
@@ -412,7 +414,7 @@ type PackageState struct {
 
 // GetTagState fetches the results for all Go subrepos at the specified Tag.
 // (Kind is "tip" or "release"; name is like "release-branch.go1.4".)
-func GetTagState(c appengine.Context, kind, name string) (*TagState, error) {
+func GetTagState(c context.Context, kind, name string) (*TagState, error) {
 	tag, err := GetTag(c, kind, name)
 	if err != nil {
 		return nil, err
@@ -425,7 +427,7 @@ func GetTagState(c appengine.Context, kind, name string) (*TagState, error) {
 	for _, pkg := range pkgs {
 		com, err := pkg.LastCommit(c)
 		if err != nil {
-			c.Warningf("%v: no Commit found: %v", pkg, err)
+			log.Warningf(c, "%v: no Commit found: %v", pkg, err)
 			continue
 		}
 		st.Packages = append(st.Packages, &PackageState{pkg, com})
@@ -456,7 +458,7 @@ func buildingKey(hash, goHash, builder string) string {
 
 // populateBuildingURLs populates each commit in Commits' buildingURLs map with the
 // URLs of builds which are currently in progress.
-func (td *uiTemplateData) populateBuildingURLs(ctx appengine.Context) {
+func (td *uiTemplateData) populateBuildingURLs(ctx context.Context) {
 	// need are memcache keys: "building|<hash>|<gohash>|<builder>"
 	// The hash is of the main "go" repo, or the subrepo commit hash.
 	// The gohash is empty for the main repo, else it's the Go hash.
@@ -495,7 +497,7 @@ func (td *uiTemplateData) populateBuildingURLs(ctx appengine.Context) {
 	m, err := memcache.GetMulti(ctx, need)
 	if err != nil {
 		// oh well. this is a cute non-critical feature anyway.
-		ctx.Debugf("GetMulti of building keys: %v", err)
+		log.Debugf(ctx, "GetMulti of building keys: %v", err)
 		return
 	}
 	for k, it := range m {
@@ -519,7 +521,7 @@ func (td *uiTemplateData) populateBuildingURLs(ctx appengine.Context) {
 }
 
 var uiTemplate = template.Must(
-	template.New("ui.html").Funcs(tmplFuncs).ParseFiles("build/ui.html"),
+	template.New("ui.html").Funcs(tmplFuncs).ParseFiles("ui.html"),
 )
 
 var tmplFuncs = template.FuncMap{
diff --git a/app/build/ui.html b/app/appengine/ui.html
similarity index 100%
rename from app/build/ui.html
rename to app/appengine/ui.html
diff --git a/app/build/update.go b/app/appengine/update.go
similarity index 95%
rename from app/build/update.go
rename to app/appengine/update.go
index 27b49ed0..5e958e11 100644
--- a/app/build/update.go
+++ b/app/appengine/update.go
@@ -11,8 +11,9 @@ import (
 	"fmt"
 	"net/http"
 
-	"appengine"
-	"appengine/datastore"
+	"golang.org/x/net/context"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
 )
 
 func init() {
@@ -45,7 +46,7 @@ func updateBenchmark(w http.ResponseWriter, r *http.Request) {
 
 	ncommit := 0
 	nrun := 0
-	tx := func(c appengine.Context) error {
+	tx := func(c context.Context) error {
 		var cr *CommitRun
 		for _, hash := range hashes {
 			// Update Commit.
diff --git a/app/cache/cache.go b/app/cache/cache.go
index 14d18384..2c1effe7 100644
--- a/app/cache/cache.go
+++ b/app/cache/cache.go
@@ -9,13 +9,14 @@ package cache
 import (
 	"bytes"
 	"compress/gzip"
+	"context"
 	"encoding/gob"
 	"fmt"
 	"net/http"
 	"time"
 
-	"appengine"
-	"appengine/memcache"
+	"google.golang.org/appengine/log"
+	"google.golang.org/appengine/memcache"
 )
 
 // TimeKey specifies the memcache entity that keeps the logical datastore time.
@@ -29,10 +30,10 @@ const (
 func newTime() uint64 { return uint64(time.Now().Unix()) << 32 }
 
 // Now returns the current logical datastore time to use for cache lookups.
-func Now(c appengine.Context) uint64 {
+func Now(c context.Context) uint64 {
 	t, err := memcache.Increment(c, TimeKey, 0, newTime())
 	if err != nil {
-		c.Errorf("cache.Now: %v", err)
+		log.Errorf(c, "cache.Now: %v", err)
 		return 0
 	}
 	return t
@@ -40,10 +41,10 @@ func Now(c appengine.Context) uint64 {
 
 // Tick sets the current logical datastore time to a never-before-used time
 // and returns that time. It should be called to invalidate the cache.
-func Tick(c appengine.Context) uint64 {
+func Tick(c context.Context) uint64 {
 	t, err := memcache.Increment(c, TimeKey, 1, newTime())
 	if err != nil {
-		c.Errorf("cache.Tick: %v", err)
+		log.Errorf(c, "cache.Tick: %v", err)
 		return 0
 	}
 	return t
@@ -52,26 +53,26 @@ func Tick(c appengine.Context) uint64 {
 // Get fetches data for name at time now from memcache and unmarshals it into
 // value. It reports whether it found the cache record and logs any errors to
 // the admin console.
-func Get(c appengine.Context, r *http.Request, now uint64, name string, value interface{}) bool {
+func Get(c context.Context, r *http.Request, now uint64, name string, value interface{}) bool {
 	if now == 0 || r.FormValue(nocache) != "" {
 		return false
 	}
 	key := fmt.Sprintf("%s.%d", name, now)
 	_, err := gzipGobCodec.Get(c, key, value)
 	if err == nil {
-		c.Debugf("cache hit %q", key)
+		log.Debugf(c, "cache hit %q", key)
 		return true
 	}
-	c.Debugf("cache miss %q", key)
+	log.Debugf(c, "cache miss %q", key)
 	if err != memcache.ErrCacheMiss {
-		c.Errorf("get cache %q: %v", key, err)
+		log.Errorf(c, "get cache %q: %v", key, err)
 	}
 	return false
 }
 
 // Set puts value into memcache under name at time now.
 // It logs any errors to the admin console.
-func Set(c appengine.Context, r *http.Request, now uint64, name string, value interface{}) {
+func Set(c context.Context, r *http.Request, now uint64, name string, value interface{}) {
 	if now == 0 || r.FormValue(nocache) != "" {
 		return
 	}
@@ -82,7 +83,7 @@ func Set(c appengine.Context, r *http.Request, now uint64, name string, value in
 		Expiration: expiry,
 	})
 	if err != nil {
-		c.Errorf("set cache %q: %v", key, err)
+		log.Errorf(c, "set cache %q: %v", key, err)
 	}
 }
 
diff --git a/app/key/key.go b/app/key/key.go
index e52554f1..b3cbd7a6 100644
--- a/app/key/key.go
+++ b/app/key/key.go
@@ -7,10 +7,11 @@
 package key
 
 import (
+	"context"
 	"sync"
 
-	"appengine"
-	"appengine/datastore"
+	"google.golang.org/appengine"
+	"google.golang.org/appengine/datastore"
 )
 
 var theKey struct {
@@ -22,11 +23,11 @@ type builderKey struct {
 	Secret string
 }
 
-func (k *builderKey) Key(c appengine.Context) *datastore.Key {
+func (k *builderKey) Key(c context.Context) *datastore.Key {
 	return datastore.NewKey(c, "BuilderKey", "root", 0, nil)
 }
 
-func Secret(c appengine.Context) string {
+func Secret(c context.Context) string {
 	// check with rlock
 	theKey.RLock()
 	k := theKey.Secret