diff --git a/maven_package.bucklet b/maven_package.bucklet
index 9992480..e8c855d 100644
--- a/maven_package.bucklet
+++ b/maven_package.bucklet
@@ -20,6 +20,7 @@
 #   repository = 'gerrit-api-repository',
 #   url = 'gs://gerrit-api/release',
 #   version = '1.0',
+#   group = 'com.google.gitiles',
 #   jar = {'gitiles-servlet': '//gitiles-servlet:servlet'},
 #   src = {'gitiles-servlet': '//gitiles-servlet:src'},
 #   doc = {'gitiles-servlet': '//gitiles-servlet:javadoc'},
@@ -29,10 +30,16 @@
     version,
     repository = None,
     url = None,
+    group = None,
     jar = {},
     src = {},
     doc = {}):
-  cmd = ['$(exe //bucklets/tools:mvn)', '-v', version, '-o', '$OUT']
+  cmd = [
+    '$(exe //bucklets/tools:mvn)',
+    '-g', group,
+    '-v', version,
+    '-o', '$OUT',
+  ]
   dep = []
 
   for type,d in [('jar', jar), ('java-source', src), ('javadoc', doc)]:
diff --git a/tools/mvn.py b/tools/mvn.py
index 80cbd60..9c97c83 100644
--- a/tools/mvn.py
+++ b/tools/mvn.py
@@ -31,17 +31,21 @@
 opts.add_option('--repository', help='maven repository id')
 opts.add_option('--url', help='maven repository url')
 opts.add_option('-o')
+opts.add_option('-g', help='maven group id')
 opts.add_option('-a', help='action (valid actions are: install,deploy)')
-opts.add_option('-v', help='gerrit version')
+opts.add_option('-v', help='package version')
 opts.add_option('-s', action='append', help='triplet of artifactId:type:path')
 
 args, ctx = opts.parse_args()
+if not args.g:
+  print('group is empty', file=stderr)
+  exit(1)
 if not args.v:
   print('version is empty', file=stderr)
   exit(1)
 
 common = [
-  '-DgroupId=com.google.gerrit',
+  '-DgroupId=%s' % args.g,
   '-Dversion=%s' % args.v,
 ]