diff --git a/pkg/directory/directory.go b/pkg/directory/directory_linux.go
similarity index 100%
rename from pkg/directory/directory.go
rename to pkg/directory/directory_linux.go
diff --git a/pkg/directory/directory_test.go b/pkg/directory/directory_test.go
index a137c59098..a8da1ac651 100644
--- a/pkg/directory/directory_test.go
+++ b/pkg/directory/directory_test.go
@@ -1,49 +1,54 @@
 package directory
 
 import (
+	"io/ioutil"
 	"os"
 	"testing"
 )
 
 // Size of an empty directory should be 0
 func TestSizeEmpty(t *testing.T) {
+	var dir string
 	var err error
-	if err = os.Mkdir("/tmp/testSizeEmptyDirectory", 0777); err != nil {
+	if dir, err = ioutil.TempDir(os.TempDir(), "testSizeEmptyDirectory"); err != nil {
 		t.Fatalf("failed to create directory: %s", err)
 	}
 
 	var size int64
-	if size, _ = Size("/tmp/testSizeEmptyDirectory"); size != 0 {
+	if size, _ = Size(dir); size != 0 {
 		t.Fatalf("empty directory has size: %d", size)
 	}
 }
 
 // Size of a directory with one empty file should be 0
 func TestSizeEmptyFile(t *testing.T) {
+	var dir string
 	var err error
-	if err = os.Mkdir("/tmp/testSizeEmptyFile", 0777); err != nil {
+	if dir, err = ioutil.TempDir(os.TempDir(), "testSizeEmptyFile"); err != nil {
 		t.Fatalf("failed to create directory: %s", err)
 	}
 
-	if _, err = os.Create("/tmp/testSizeEmptyFile/file"); err != nil {
+	var file *os.File
+	if file, err = ioutil.TempFile(dir, "file"); err != nil {
 		t.Fatalf("failed to create file: %s", err)
 	}
 
 	var size int64
-	if size, _ = Size("/tmp/testSizeEmptyFile"); size != 0 {
+	if size, _ = Size(file.Name()); size != 0 {
 		t.Fatalf("directory with one file has size: %d", size)
 	}
 }
 
 // Size of a directory with one 5-byte file should be 5
 func TestSizeNonemptyFile(t *testing.T) {
+	var dir string
 	var err error
-	if err = os.Mkdir("/tmp/testSizeNonemptyFile", 0777); err != nil {
+	if dir, err = ioutil.TempDir(os.TempDir(), "testSizeNonemptyFile"); err != nil {
 		t.Fatalf("failed to create directory: %s", err)
 	}
 
 	var file *os.File
-	if file, err = os.Create("/tmp/testSizeNonemptyFile/file"); err != nil {
+	if file, err = ioutil.TempFile(dir, "file"); err != nil {
 		t.Fatalf("failed to create file: %s", err)
 	}
 
@@ -51,33 +56,41 @@ func TestSizeNonemptyFile(t *testing.T) {
 	file.Write(d)
 
 	var size int64
-	if size, _ = Size("/tmp/testSizeNonemptyFile"); size != 5 {
+	if size, _ = Size(file.Name()); size != 5 {
 		t.Fatalf("directory with one 5-byte file has size: %d", size)
 	}
 }
 
 // Size of a directory with one empty directory should be 0
 func TestSizeNestedDirectoryEmpty(t *testing.T) {
+	var dir string
 	var err error
-	if err = os.MkdirAll("/tmp/testSizeNestedDirectoryEmpty/nested", 0777); err != nil {
+	if dir, err = ioutil.TempDir(os.TempDir(), "testSizeNestedDirectoryEmpty"); err != nil {
 		t.Fatalf("failed to create directory: %s", err)
 	}
+	if dir, err = ioutil.TempDir(dir, "nested"); err != nil {
+		t.Fatalf("failed to create nested directory: %s", err)
+	}
 
 	var size int64
-	if size, _ = Size("/tmp/testSizeNestedDirectoryEmpty"); size != 0 {
+	if size, _ = Size(dir); size != 0 {
 		t.Fatalf("directory with one empty directory has size: %d", size)
 	}
 }
 
 // Test directory with 1 file and 1 empty directory
 func TestSizeFileAndNestedDirectoryEmpty(t *testing.T) {
+	var dir string
 	var err error
-	if err = os.MkdirAll("/tmp/testSizeFileAndNestedDirectoryEmpty/nested", 0777); err != nil {
+	if dir, err = ioutil.TempDir(os.TempDir(), "testSizeFileAndNestedDirectoryEmpty"); err != nil {
 		t.Fatalf("failed to create directory: %s", err)
 	}
+	if dir, err = ioutil.TempDir(dir, "nested"); err != nil {
+		t.Fatalf("failed to create nested directory: %s", err)
+	}
 
 	var file *os.File
-	if file, err = os.Create("/tmp/testSizeFileAndNestedDirectoryEmpty/file"); err != nil {
+	if file, err = ioutil.TempFile(dir, "file"); err != nil {
 		t.Fatalf("failed to create file: %s", err)
 	}
 
@@ -85,20 +98,24 @@ func TestSizeFileAndNestedDirectoryEmpty(t *testing.T) {
 	file.Write(d)
 
 	var size int64
-	if size, _ = Size("/tmp/testSizeFileAndNestedDirectoryEmpty"); size != 6 {
+	if size, _ = Size(dir); size != 6 {
 		t.Fatalf("directory with 6-byte file and empty directory has size: %d", size)
 	}
 }
 
 // Test directory with 1 file and 1 non-empty directory
 func TestSizeFileAndNestedDirectoryNonempty(t *testing.T) {
+	var dir, dirNested string
 	var err error
-	if err = os.MkdirAll("/tmp/testSizeFileAndNestedDirectoryEmpty/nested", 0777); err != nil {
+	if dir, err = ioutil.TempDir(os.TempDir(), "TestSizeFileAndNestedDirectoryNonempty"); err != nil {
 		t.Fatalf("failed to create directory: %s", err)
 	}
+	if dirNested, err = ioutil.TempDir(dir, "nested"); err != nil {
+		t.Fatalf("failed to create nested directory: %s", err)
+	}
 
 	var file *os.File
-	if file, err = os.Create("/tmp/testSizeFileAndNestedDirectoryEmpty/file"); err != nil {
+	if file, err = ioutil.TempFile(dir, "file"); err != nil {
 		t.Fatalf("failed to create file: %s", err)
 	}
 
@@ -106,15 +123,15 @@ func TestSizeFileAndNestedDirectoryNonempty(t *testing.T) {
 	file.Write(data)
 
 	var nestedFile *os.File
-	if nestedFile, err = os.Create("/tmp/testSizeFileAndNestedDirectoryEmpty/nested/file"); err != nil {
-		t.Fatalf("failed to create file: %s", err)
+	if nestedFile, err = ioutil.TempFile(dirNested, "file"); err != nil {
+		t.Fatalf("failed to create file in nested directory: %s", err)
 	}
 
 	nestedData := []byte{100, 111, 99, 107, 101, 114}
 	nestedFile.Write(nestedData)
 
 	var size int64
-	if size, _ = Size("/tmp/testSizeFileAndNestedDirectoryEmpty"); size != 12 {
-		t.Fatalf("directory with 6-byte file and empty directory has size: %d", size)
+	if size, _ = Size(dir); size != 12 {
+		t.Fatalf("directory with 6-byte file and nested directory with 6-byte file has size: %d", size)
 	}
 }
diff --git a/pkg/directory/directory_windows.go b/pkg/directory/directory_windows.go
new file mode 100644
index 0000000000..7a9f8cb68c
--- /dev/null
+++ b/pkg/directory/directory_windows.go
@@ -0,0 +1,28 @@
+// +build windows
+
+package directory
+
+import (
+	"os"
+	"path/filepath"
+)
+
+// Size walks a directory tree and returns its total size in bytes.
+func Size(dir string) (size int64, err error) {
+	err = filepath.Walk(dir, func(d string, fileInfo os.FileInfo, e error) error {
+		// Ignore directory sizes
+		if fileInfo == nil {
+			return nil
+		}
+
+		s := fileInfo.Size()
+		if fileInfo.IsDir() || s == 0 {
+			return nil
+		}
+
+		size += s
+
+		return nil
+	})
+	return
+}