diff --git a/README.md b/README.md
index 4cb606b..ed89d38 100644
--- a/README.md
+++ b/README.md
@@ -32,6 +32,14 @@
 - `--prefix=[CONTEXTPATH]`
 - `--host=[HOSTNAME]`
 - `--gitbucket.home=[DATA_DIR]`
+- `--temp_dir=[TEMP_DIR]`
+
+`TEMP_DIR` is used as the [temporary directory for the jetty application context](https://www.eclipse.org/jetty/documentation/9.3.x/ref-temporary-directories.html).
+This is the directory into which the gitbucket.war file is unpacked, the source
+files are compiled, etc.  
+If given this parameter **must** match the path of an existing directory
+or the application will quit reporting an error; if not given the path used
+will be a `tmp` directory inside the gitbucket home.
 
 You can also deploy gitbucket.war to a servlet container which supports Servlet 3.0 (like Jetty, Tomcat, JBoss, etc)
 
diff --git a/src/main/java/JettyLauncher.java b/src/main/java/JettyLauncher.java
index 01168e0..d810941 100644
--- a/src/main/java/JettyLauncher.java
+++ b/src/main/java/JettyLauncher.java
@@ -12,6 +12,7 @@
         int port = 8080;
         InetSocketAddress address = null;
         String contextPath = "/";
+        String tmpDirPath="";
         boolean forceHttps = false;
 
         for(String arg: args) {
@@ -29,6 +30,8 @@
                         }
                     } else if(dim[0].equals("--gitbucket.home")){
                         System.setProperty("gitbucket.home", dim[1]);
+                    } else if(dim[0].equals("--temp_dir")){
+                        tmpDirPath = dim[1];
                     }
                 }
             }
@@ -53,9 +56,21 @@
 
         WebAppContext context = new WebAppContext();
 
-        File tmpDir = new File(getGitBucketHome(), "tmp");
-        if(!tmpDir.exists()){
-            tmpDir.mkdirs();
+        File tmpDir;
+        if(tmpDirPath.equals("")){
+            tmpDir = new File(getGitBucketHome(), "tmp");
+            if(!tmpDir.exists()){
+                tmpDir.mkdirs();
+            }
+        } else {
+            tmpDir = new File(tmpDirPath);
+            if(!tmpDir.exists()){
+                throw new java.io.FileNotFoundException(
+                    String.format("temp_dir \"%s\" not found", tmpDirPath));
+            } else if(!tmpDir.isDirectory()) {
+                throw new IllegalArgumentException(
+                    String.format("temp_dir \"%s\" is not a directory", tmpDirPath));
+            }
         }
         context.setTempDirectory(tmpDir);