diff --git a/gerrit-common/src/main/java/com/google/gerrit/common/FileUtil.java b/gerrit-common/src/main/java/com/google/gerrit/common/FileUtil.java
index bed10d656a..aa2fcbc36e 100644
--- a/gerrit-common/src/main/java/com/google/gerrit/common/FileUtil.java
+++ b/gerrit-common/src/main/java/com/google/gerrit/common/FileUtil.java
@@ -21,6 +21,7 @@ import org.eclipse.jgit.util.IO;
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.nio.file.Path;
 import java.util.Arrays;
 
 public class FileUtil {
@@ -42,6 +43,11 @@ public class FileUtil {
     }
   }
 
+  public static void chmod(final int mode, final Path path) {
+    // TODO(dborowitz): Is there a portable way to do this with NIO?
+    chmod(mode, path.toFile());
+  }
+
   public static void chmod(final int mode, final File path) {
     path.setReadable(false, false /* all */);
     path.setWritable(false, false /* all */);
@@ -63,4 +69,4 @@ public class FileUtil {
 
   private FileUtil() {
   }
-}
\ No newline at end of file
+}
diff --git a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitWebServlet.java b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitWebServlet.java
index 9a7cab01bf..a185985cad 100644
--- a/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitWebServlet.java
+++ b/gerrit-httpd/src/main/java/com/google/gerrit/httpd/gitweb/GitWebServlet.java
@@ -62,6 +62,7 @@ import java.io.OutputStream;
 import java.io.PrintWriter;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.nio.file.Files;
 import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.HashSet;
@@ -143,10 +144,11 @@ class GitWebServlet extends HttpServlet {
 
   private void makeSiteConfig(final SitePaths site,
       final GerritConfig gerritConfig) throws IOException {
-    if (!site.tmp_dir.exists()) {
-      site.tmp_dir.mkdirs();
+    if (!Files.exists(site.tmp_dir)) {
+      Files.createDirectories(site.tmp_dir);
     }
-    File myconf = File.createTempFile("gitweb_config", ".perl", site.tmp_dir);
+    File myconf = Files.createTempFile(site.tmp_dir, "gitweb_config", ".perl")
+        .toFile();
 
     // To make our configuration file only readable or writable by us;
     // this reduces the chances of someone tampering with the file.
diff --git a/gerrit-pgm/src/main/java/com/google/gerrit/pgm/init/api/InitUtil.java b/gerrit-pgm/src/main/java/com/google/gerrit/pgm/init/api/InitUtil.java
index 881208d552..ac911a472c 100644
--- a/gerrit-pgm/src/main/java/com/google/gerrit/pgm/init/api/InitUtil.java
+++ b/gerrit-pgm/src/main/java/com/google/gerrit/pgm/init/api/InitUtil.java
@@ -34,6 +34,8 @@ import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.UnknownHostException;
 import java.nio.ByteBuffer;
+import java.nio.file.Files;
+import java.nio.file.Path;
 
 /** Utility functions to help initialize a site. */
 public class InitUtil {
@@ -51,9 +53,18 @@ public class InitUtil {
     }
   }
 
-  public static void mkdir(final File path) {
-    if (!path.isDirectory() && !path.mkdir()) {
-      throw die("Cannot make directory " + path);
+  public static void mkdir(File file) {
+    mkdir(file.toPath());
+  }
+
+  public static void mkdir(Path path) {
+    if (Files.isDirectory(path)) {
+      return;
+    }
+    try {
+      Files.createDirectory(path);
+    } catch (IOException e) {
+      throw die("Cannot make directory " + path, e);
     }
   }
 
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/config/SitePaths.java b/gerrit-server/src/main/java/com/google/gerrit/server/config/SitePaths.java
index 1cd8fb29ab..c39d7ba263 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/config/SitePaths.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/config/SitePaths.java
@@ -33,7 +33,7 @@ public final class SitePaths {
   public final File bin_dir;
   public final File etc_dir;
   public final File lib_dir;
-  public final File tmp_dir;
+  public final Path tmp_dir;
   public final File logs_dir;
   public final File plugins_dir;
   public final File data_dir;
@@ -68,11 +68,12 @@ public final class SitePaths {
   public SitePaths(final @SitePath Path sitePath) throws FileNotFoundException {
     // TODO(dborowitz): Convert all of these to Paths.
     site_path = sitePath.toFile();
+    Path p = sitePath;
 
     bin_dir = new File(site_path, "bin");
     etc_dir = new File(site_path, "etc");
     lib_dir = new File(site_path, "lib");
-    tmp_dir = new File(site_path, "tmp");
+    tmp_dir = p.resolve("tmp");
     plugins_dir = new File(site_path, "plugins");
     data_dir = new File(site_path, "data");
     logs_dir = new File(site_path, "logs");
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/plugins/JarPluginProvider.java b/gerrit-server/src/main/java/com/google/gerrit/server/plugins/JarPluginProvider.java
index 53f39f1cb5..5c0b41c5d6 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/plugins/JarPluginProvider.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/plugins/JarPluginProvider.java
@@ -31,6 +31,7 @@ import java.io.InputStream;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.net.URLClassLoader;
+import java.nio.file.Files;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
 import java.util.Date;
@@ -47,7 +48,8 @@ public class JarPluginProvider implements ServerPluginProvider {
 
   @Inject
   JarPluginProvider(SitePaths sitePaths) {
-    tmpDir = sitePaths.tmp_dir;
+    // TODO(dborowitz): Convert to NIO.
+    tmpDir = sitePaths.tmp_dir.toFile();
   }
 
   @Override
@@ -111,10 +113,11 @@ public class JarPluginProvider implements ServerPluginProvider {
 
   public static File storeInTemp(String pluginName, InputStream in,
       SitePaths sitePaths) throws IOException {
-    if (!sitePaths.tmp_dir.exists()) {
-      sitePaths.tmp_dir.mkdirs();
+    if (!Files.exists(sitePaths.tmp_dir)) {
+      Files.createDirectories(sitePaths.tmp_dir);
     }
-    return asTemp(in, tempNameFor(pluginName), ".jar", sitePaths.tmp_dir);
+    return asTemp(in, tempNameFor(pluginName), ".jar",
+        sitePaths.tmp_dir.toFile());
   }
 
   private ServerPlugin loadJarPlugin(String name, File srcJar,