diff --git a/hack/cmd/teststale/teststale.go b/hack/cmd/teststale/teststale.go
new file mode 100644
index 00000000000..2da1bb85677
--- /dev/null
+++ b/hack/cmd/teststale/teststale.go
@@ -0,0 +1,209 @@
+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// teststale checks the staleness of a test binary. go test -c builds a test
+// binary but it does no staleness check. In other words, every time one runs
+// go test -c, it compiles the test packages and links the binary even when
+// nothing has changed. This program helps to mitigate that problem by allowing
+// to check the staleness of a given test package and its binary.
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"time"
+
+	"github.com/golang/glog"
+)
+
+const usageHelp = "" +
+	`This program checks the staleness of a given test package and its test
+binary so that one can make a decision about re-building the test binary.
+
+Usage:
+  teststale -binary=/path/to/test/binary -package=package
+
+Example:
+  teststale -binary="$HOME/gosrc/bin/e2e.test" -package="k8s.io/kubernetes/test/e2e"
+
+`
+
+var (
+	binary  = flag.String("binary", "", "filesystem path to the test binary file. Example: \"$HOME/gosrc/bin/e2e.test\"")
+	pkgPath = flag.String("package", "", "import path of the test package in the format used while importing packages. Example: \"k8s.io/kubernetes/test/e2e\"")
+)
+
+func usage() {
+	fmt.Fprintln(os.Stderr, usageHelp)
+	fmt.Fprintln(os.Stderr, "Flags:")
+	flag.PrintDefaults()
+	os.Exit(2)
+}
+
+// golist is an interface emulating the `go list` command to get package information.
+// TODO: Evaluate using `go/build` package instead. It doesn't provide staleness
+// information, but we can probably run `go list` and `go/build.Import()` concurrently
+// in goroutines and merge the results. Evaluate if that's faster.
+type golist interface {
+	pkgInfo(pkgPaths []string) ([]pkg, error)
+}
+
+// execmd implements the `golist` interface.
+type execcmd struct {
+	cmd  string
+	args []string
+	env  []string
+}
+
+func (e *execcmd) pkgInfo(pkgPaths []string) ([]pkg, error) {
+	args := append(e.args, pkgPaths...)
+	cmd := exec.Command(e.cmd, args...)
+	cmd.Env = e.env
+
+	stdout, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, fmt.Errorf("failed to obtain the metadata output stream: %v", err)
+	}
+
+	dec := json.NewDecoder(stdout)
+
+	// Start executing the command
+	if err := cmd.Start(); err != nil {
+		return nil, fmt.Errorf("command did not start: %v", err)
+	}
+
+	var pkgs []pkg
+	for {
+		var p pkg
+		if err := dec.Decode(&p); err == io.EOF {
+			break
+		} else if err != nil {
+			return nil, fmt.Errorf("failed to unmarshal metadata for package %s: %v", p.ImportPath, err)
+		}
+		pkgs = append(pkgs, p)
+	}
+
+	if err := cmd.Wait(); err != nil {
+		return nil, fmt.Errorf("command did not complete: %v", err)
+	}
+	return pkgs, nil
+}
+
+type pkg struct {
+	Dir          string
+	ImportPath   string
+	Target       string
+	Stale        bool
+	TestGoFiles  []string
+	TestImports  []string
+	XTestGoFiles []string
+	XTestImports []string
+}
+
+func (p *pkg) isNewerThan(cmd golist, buildTime time.Time) bool {
+	// If the package itself is stale, then we have to rebuild the whole thing anyway.
+	if p.Stale {
+		return true
+	}
+
+	// Test for file staleness
+	for _, f := range p.TestGoFiles {
+		if isNewerThan(filepath.Join(p.Dir, f), buildTime) {
+			glog.V(4).Infof("test Go file %s is stale", f)
+			return true
+		}
+	}
+	for _, f := range p.XTestGoFiles {
+		if isNewerThan(filepath.Join(p.Dir, f), buildTime) {
+			glog.V(4).Infof("external test Go file %s is stale", f)
+			return true
+		}
+	}
+
+	imps := []string{}
+	imps = append(imps, p.TestImports...)
+	imps = append(imps, p.XTestImports...)
+
+	// This calls `go list` the second time. This is required because the first
+	// call to `go list` checks the staleness of the package in question by
+	// looking the non-test dependencies, but it doesn't look at the test
+	// dependencies. However, it returns the list of test dependencies. This
+	// second call to `go list` checks the staleness of all the test
+	// dependencies.
+	pkgs, err := cmd.pkgInfo(imps)
+	if err != nil || len(pkgs) < 1 {
+		glog.V(4).Infof("failed to obtain metadata for packages %s: %v", imps, err)
+		return true
+	}
+
+	for _, p := range pkgs {
+		if p.Stale {
+			glog.V(4).Infof("import %q is stale", p.ImportPath)
+			return true
+		}
+	}
+
+	return false
+}
+
+func isNewerThan(filename string, buildTime time.Time) bool {
+	stat, err := os.Stat(filename)
+	if err != nil {
+		return true
+	}
+	return stat.ModTime().After(buildTime)
+}
+
+// isTestStale checks if the test binary is stale and needs to rebuilt.
+// Some of the ideas here are inspired by how Go does staleness checks.
+func isTestStale(cmd golist, binPath, pkgPath string) bool {
+	bStat, err := os.Stat(binPath)
+	if err != nil {
+		glog.V(4).Infof("Couldn't obtain the modified time of the binary %s: %v", binPath, err)
+		return true
+	}
+	buildTime := bStat.ModTime()
+
+	pkgs, err := cmd.pkgInfo([]string{pkgPath})
+	if err != nil || len(pkgs) < 1 {
+		glog.V(4).Infof("Couldn't retrieve test package information for package %s: %v", pkgPath, err)
+		return false
+	}
+
+	return pkgs[0].isNewerThan(cmd, buildTime)
+}
+
+func main() {
+	flag.Usage = usage
+	flag.Parse()
+
+	cmd := &execcmd{
+		cmd: "go",
+		args: []string{
+			"list",
+			"-json",
+		},
+		env: os.Environ(),
+	}
+	if !isTestStale(cmd, *binary, *pkgPath) {
+		os.Exit(1)
+	}
+}
diff --git a/hack/cmd/teststale/teststale_test.go b/hack/cmd/teststale/teststale_test.go
new file mode 100644
index 00000000000..45096a8a8e2
--- /dev/null
+++ b/hack/cmd/teststale/teststale_test.go
@@ -0,0 +1,325 @@
+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"math/rand"
+	"os"
+	"path"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+const (
+	// seed for rand.Source to generate data for files
+	seed int64 = 42
+
+	// 1K binary file
+	binLen = 1024
+
+	// Directory of the test package relative to $GOPATH
+	testImportDir = "example.com/proj/pkg"
+)
+
+var (
+	pastHour = time.Now().Add(-1 * time.Hour)
+
+	// The test package we are testing against
+	testPkg = path.Join(testImportDir, "test")
+)
+
+// fakegolist implements the `golist` interface providing fake package information for testing.
+type fakegolist struct {
+	dir       string
+	importMap map[string]pkg
+	testFiles []string
+	binfile   string
+}
+
+func newFakegolist() (*fakegolist, error) {
+	dir, err := ioutil.TempDir("", "teststale")
+	if err != nil {
+		// test can't proceed without a temp directory.
+		return nil, fmt.Errorf("failed to create a temp directory for testing: %v", err)
+	}
+
+	// Set the temp directory as the $GOPATH
+	if err := os.Setenv("GOPATH", dir); err != nil {
+		// can't proceed without pointing the $GOPATH to the temp directory.
+		return nil, fmt.Errorf("failed to set \"$GOPATH\" pointing to %q: %v", dir, err)
+	}
+
+	// Setup $GOPATH directory layout.
+	// Yeah! I am bored of repeatedly writing "if err != nil {}"!
+	if os.MkdirAll(filepath.Join(dir, "bin"), 0750) != nil ||
+		os.MkdirAll(filepath.Join(dir, "pkg", "linux_amd64"), 0750) != nil ||
+		os.MkdirAll(filepath.Join(dir, "src"), 0750) != nil {
+		return nil, fmt.Errorf("failed to setup the $GOPATH directory structure")
+	}
+
+	// Create a temp file to represent the test binary.
+	binfile, err := ioutil.TempFile("", "testbin")
+	if err != nil {
+		return nil, fmt.Errorf("failed to create the temp file to represent the test binary: %v", err)
+	}
+
+	// Could have used crypto/rand instead, but it doesn't matter.
+	rr := rand.New(rand.NewSource(42))
+	bin := make([]byte, binLen)
+	if _, err = rr.Read(bin); err != nil {
+		return nil, fmt.Errorf("couldn't read from the random source: %v", err)
+	}
+	if _, err := binfile.Write(bin); err != nil {
+		return nil, fmt.Errorf("couldn't write to the binary file %q: %v", binfile.Name(), err)
+	}
+	if err := binfile.Close(); err != nil {
+		// It is arguable whether this should be fatal.
+		return nil, fmt.Errorf("failed to close the binary file %q: %v", binfile.Name(), err)
+	}
+
+	if err := os.Chtimes(binfile.Name(), time.Now(), time.Now()); err != nil {
+		return nil, fmt.Errorf("failed to modify the mtime of the binary file %q: %v", binfile.Name(), err)
+	}
+
+	// Create test source files directory.
+	testdir := filepath.Join(dir, "src", testPkg)
+	if err := os.MkdirAll(testdir, 0750); err != nil {
+		return nil, fmt.Errorf("failed to create test source directory %q: %v", testdir, err)
+	}
+
+	fgl := &fakegolist{
+		dir: dir,
+		importMap: map[string]pkg{
+			"example.com/proj/pkg/test": {
+				Dir:        path.Join(dir, "src", testPkg),
+				ImportPath: testPkg,
+				Target:     path.Join(dir, "pkg", "linux_amd64", testImportDir, "test.a"),
+				Stale:      false,
+				TestGoFiles: []string{
+					"foo_test.go",
+					"bar_test.go",
+				},
+				TestImports: []string{
+					"example.com/proj/pkg/p1",
+					"example.com/proj/pkg/p1/c11",
+					"example.com/proj/pkg/p2",
+					"example.com/proj/cmd/p3/c12/c23",
+					"strings",
+					"testing",
+				},
+				XTestGoFiles: []string{
+					"xfoo_test.go",
+					"xbar_test.go",
+					"xbaz_test.go",
+				},
+				XTestImports: []string{
+					"example.com/proj/pkg/test",
+					"example.com/proj/pkg/p1",
+					"example.com/proj/cmd/p3/c12/c23",
+					"os",
+					"testing",
+				},
+			},
+			"example.com/proj/pkg/p1":         {Stale: false},
+			"example.com/proj/pkg/p1/c11":     {Stale: false},
+			"example.com/proj/pkg/p2":         {Stale: false},
+			"example.com/proj/cmd/p3/c12/c23": {Stale: false},
+			"strings":                         {Stale: false},
+			"testing":                         {Stale: false},
+			"os":                              {Stale: false},
+		},
+		testFiles: []string{
+			"foo_test.go",
+			"bar_test.go",
+			"xfoo_test.go",
+			"xbar_test.go",
+			"xbaz_test.go",
+		},
+		binfile: binfile.Name(),
+	}
+
+	// Create test source files.
+	for _, fn := range fgl.testFiles {
+		fp := filepath.Join(testdir, fn)
+		if _, err := os.Create(fp); err != nil {
+			return nil, fmt.Errorf("failed to create the test file %q: %v", fp, err)
+		}
+		if err := os.Chtimes(fp, time.Now(), pastHour); err != nil {
+			return nil, fmt.Errorf("failed to modify the mtime of the test file %q: %v", binfile.Name(), err)
+		}
+	}
+
+	return fgl, nil
+}
+
+func (fgl *fakegolist) pkgInfo(pkgPaths []string) ([]pkg, error) {
+	var pkgs []pkg
+	for _, path := range pkgPaths {
+		p, ok := fgl.importMap[path]
+		if !ok {
+			return nil, fmt.Errorf("package %q not found", path)
+		}
+		pkgs = append(pkgs, p)
+	}
+	return pkgs, nil
+}
+
+func (fgl *fakegolist) chMtime(filename string, mtime time.Time) error {
+	for _, fn := range fgl.testFiles {
+		if fn == filename {
+			fp := filepath.Join(fgl.dir, "src", testPkg, fn)
+			if err := os.Chtimes(fp, time.Now(), mtime); err != nil {
+				return fmt.Errorf("failed to modify the mtime of %q: %v", filename, err)
+			}
+			return nil
+		}
+	}
+	return fmt.Errorf("file %q not found", filename)
+}
+
+func (fgl *fakegolist) chStale(pkg string, stale bool) error {
+	if p, ok := fgl.importMap[pkg]; ok {
+		p.Stale = stale
+		fgl.importMap[pkg] = p
+		return nil
+	}
+	return fmt.Errorf("package %q not found", pkg)
+}
+
+func (fgl *fakegolist) cleanup() {
+	os.RemoveAll(fgl.dir)
+	os.Remove(fgl.binfile)
+}
+
+func TestIsTestStale(t *testing.T) {
+	cases := []struct {
+		fileMtime    map[string]time.Time
+		pkgStaleness map[string]bool
+		result       bool
+	}{
+		// Basic test: binary is fresh, all modifications were before the binary was built.
+		{
+			result: false,
+		},
+		// A local test file is new, hence binary must be stale.
+		{
+			fileMtime: map[string]time.Time{
+				"foo_test.go": time.Now().Add(1 * time.Hour),
+			},
+			result: true,
+		},
+		// Test package is new, so binary must be stale.
+		{
+			pkgStaleness: map[string]bool{
+				"example.com/proj/pkg/test": true,
+			},
+			result: true,
+		},
+		// Test package dependencies are new, so binary must be stale.
+		{
+			pkgStaleness: map[string]bool{
+				"example.com/proj/cmd/p3/c12/c23": true,
+				"strings":                         true,
+			},
+			result: true,
+		},
+		// External test files are new, hence binary must be stale.
+		{
+			fileMtime: map[string]time.Time{
+				"xfoo_test.go": time.Now().Add(1 * time.Hour),
+				"xbar_test.go": time.Now().Add(2 * time.Hour),
+			},
+			result: true,
+		},
+		// External test dependency is new, so binary must be stale.
+		{
+			pkgStaleness: map[string]bool{
+				"os": true,
+			},
+			result: true,
+		},
+		// Multiple source files and dependencies are new, so binary must be stale.
+		{
+			fileMtime: map[string]time.Time{
+				"foo_test.go":  time.Now().Add(1 * time.Hour),
+				"xfoo_test.go": time.Now().Add(2 * time.Hour),
+				"xbar_test.go": time.Now().Add(3 * time.Hour),
+			},
+			pkgStaleness: map[string]bool{
+				"example.com/proj/pkg/p1":         true,
+				"example.com/proj/pkg/p1/c11":     true,
+				"example.com/proj/pkg/p2":         true,
+				"example.com/proj/cmd/p3/c12/c23": true,
+				"strings":                         true,
+				"os":                              true,
+			},
+			result: true,
+		},
+		// Everything is new, so binary must be stale.
+		{
+			fileMtime: map[string]time.Time{
+				"foo_test.go":  time.Now().Add(3 * time.Hour),
+				"bar_test.go":  time.Now().Add(1 * time.Hour),
+				"xfoo_test.go": time.Now().Add(2 * time.Hour),
+				"xbar_test.go": time.Now().Add(1 * time.Hour),
+				"xbaz_test.go": time.Now().Add(2 * time.Hour),
+			},
+			pkgStaleness: map[string]bool{
+				"example.com/proj/pkg/p1":         true,
+				"example.com/proj/pkg/p1/c11":     true,
+				"example.com/proj/pkg/p2":         true,
+				"example.com/proj/cmd/p3/c12/c23": true,
+				"example.com/proj/pkg/test":       true,
+				"strings":                         true,
+				"testing":                         true,
+				"os":                              true,
+			},
+			result: true,
+		},
+	}
+
+	for _, tc := range cases {
+		fgl, err := newFakegolist()
+		if err != nil {
+			t.Fatalf("failed to setup the test: %v", err)
+		}
+		defer fgl.cleanup()
+
+		for fn, mtime := range tc.fileMtime {
+			if err := fgl.chMtime(fn, mtime); err != nil {
+				t.Fatalf("failed to change the mtime of %q: %v", fn, err)
+			}
+		}
+
+		for pkg, stale := range tc.pkgStaleness {
+			if err := fgl.chStale(pkg, stale); err != nil {
+				t.Fatalf("failed to change the staleness of %q: %v", pkg, err)
+			}
+		}
+
+		if tc.result != isTestStale(fgl, fgl.binfile, testPkg) {
+			if tc.result {
+				t.Errorf("Expected test package %q to be stale", testPkg)
+			} else {
+				t.Errorf("Expected test package %q to be not stale", testPkg)
+			}
+		}
+	}
+}
diff --git a/hack/lib/golang.sh b/hack/lib/golang.sh
index aa775c3150b..a7af15c38ff 100755
--- a/hack/lib/golang.sh
+++ b/hack/lib/golang.sh
@@ -377,6 +377,25 @@ kube::golang::fallback_if_stdlib_not_installable() {
   use_go_build=true
 }
 
+# Builds the toolchain necessary for building kube. This needs to be
+# built only on the host platform.
+# TODO: This builds only the `teststale` binary right now. As we expand
+# this function's capabilities we need to find this a right home.
+# Ideally, not a shell script because testing shell scripts is painful.
+kube::golang::build_kube_toolchain() {
+  local targets=(
+    hack/cmd/teststale
+  )
+
+  local binaries
+  binaries=($(kube::golang::binaries_from_targets "${targets[@]}"))
+
+  kube::log::status "Building the toolchain targets:" "${binaries[@]}"
+  go install "${goflags[@]:+${goflags[@]}}" \
+        -ldflags "${goldflags}" \
+        "${binaries[@]:+${binaries[@]}}"
+}
+
 # Try and replicate the native binary placement of go install without
 # calling go install.
 kube::golang::output_filename_for_binary() {
@@ -449,12 +468,39 @@ kube::golang::build_binaries_for_platform() {
   for test in "${tests[@]:+${tests[@]}}"; do
     local outfile=$(kube::golang::output_filename_for_binary "${test}" \
       "${platform}")
+
+    local testpkg="$(dirname ${test})"
+
+    # Staleness check always happens on the host machine, so we don't
+    # have to locate the `teststale` binaries for the other platforms.
+    # Since we place the host binaries in `$KUBE_GOPATH/bin`, we can
+    # assume that the binary exists there, if it exists at all.
+    # Otherwise, something has gone wrong with building the `teststale`
+    # binary and we should safely proceed building the test binaries
+    # assuming that they are stale. There is no good reason to error
+    # out.
+    if test -x "${KUBE_GOPATH}/bin/teststale" && ! "${KUBE_GOPATH}/bin/teststale" -binary "${outfile}" -package "${testpkg}"
+    then
+      continue
+    fi
+
+    # `go test -c` below directly builds the binary. It builds the packages,
+    # but it never installs them. `go test -i` only installs the dependencies
+    # of the test, but not the test package itself. So neither `go test -c`
+    # nor `go test -i` installs, for example, test/e2e.a. And without that,
+    # doing a staleness check on k8s.io/kubernetes/test/e2e package always
+    # returns true (always stale). And that's why we need to install the
+    # test package.
+    go install "${goflags[@]:+${goflags[@]}}" \
+        -ldflags "${goldflags}" \
+        "${testpkg}"
+
     mkdir -p "$(dirname ${outfile})"
     go test -c \
       "${goflags[@]:+${goflags[@]}}" \
       -ldflags "${goldflags}" \
       -o "${outfile}" \
-      "$(dirname ${test})"
+      "${testpkg}"
   done
 }
 
@@ -549,6 +595,9 @@ kube::golang::build_binaries() {
       fi
     fi
 
+    # First build the toolchain before building any other targets
+    kube::golang::build_kube_toolchain
+
     if [[ "${parallel}" == "true" ]]; then
       kube::log::status "Building go targets for ${platforms[@]} in parallel (output will appear in a burst when complete):" "${targets[@]}"
       local platform