diff --git a/constants/index.js b/constants/index.js
index ba97e91..2300271 100644
--- a/constants/index.js
+++ b/constants/index.js
@@ -30,4 +30,4 @@ module.exports = {
   FILEPATH_VAR: 'filepath',
   TITLE_VAR: 'title',
   DISPLAY_NAME_VAR: 'displayName',
-};
\ No newline at end of file
+};
diff --git a/index.js b/index.js
index 13d67d4..9a4a937 100644
--- a/index.js
+++ b/index.js
@@ -25,7 +25,7 @@ const processor = (report, reporterOptions = {}, jestRootDir = null) => {
   mkdirp.sync(path.dirname(finalOutput));
 
   // Write data to file
-  fs.writeFileSync(finalOutput, xml(jsonResults, { indent: '  ' }));
+  fs.writeFileSync(finalOutput, xml(jsonResults, { indent: '  ', declaration: true }));
 
   // Jest 18 compatibility
   return report;
@@ -70,4 +70,3 @@ function JestJUnit (globalConfig, options) {
 }
 
 module.exports = JestJUnit;
-