diff --git a/inttest/bug_5_rt.erl b/inttest/bug_5_rt.erl
index a06b69331..8894cb570 100644
--- a/inttest/bug_5_rt.erl
+++ b/inttest/bug_5_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(bug_5_rt).
 
 -compile(export_all).
diff --git a/inttest/ct1/ct1_rt.erl b/inttest/ct1/ct1_rt.erl
index f9de372b3..dc8309556 100644
--- a/inttest/ct1/ct1_rt.erl
+++ b/inttest/ct1/ct1_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(ct1_rt).
 
 -compile(export_all).
diff --git a/inttest/ct2/ct2_rt.erl b/inttest/ct2/ct2_rt.erl
index ecab0e486..8a0eb0aa6 100644
--- a/inttest/ct2/ct2_rt.erl
+++ b/inttest/ct2/ct2_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(ct2_rt).
 
 -compile(export_all).
diff --git a/inttest/depplugins/depplugins_rt.erl b/inttest/depplugins/depplugins_rt.erl
index a45fa93ab..7bcfe86e9 100644
--- a/inttest/depplugins/depplugins_rt.erl
+++ b/inttest/depplugins/depplugins_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 %%% @doc Plugin handling test
 %%%
 %%% This test checks if plugins are loaded correctly.
diff --git a/inttest/eunit/eunit_rt.erl b/inttest/eunit/eunit_rt.erl
index 47f3331e7..1d714049e 100644
--- a/inttest/eunit/eunit_rt.erl
+++ b/inttest/eunit/eunit_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(eunit_rt).
 -export([files/0, run/1]).
 
diff --git a/inttest/rgen1/rgen1_rt.erl b/inttest/rgen1/rgen1_rt.erl
index 68b6eaf8a..1bf36c264 100644
--- a/inttest/rgen1/rgen1_rt.erl
+++ b/inttest/rgen1/rgen1_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(rgen1_rt).
 
 -compile(export_all).
diff --git a/inttest/t_custom_config/t_custom_config_rt.erl b/inttest/t_custom_config/t_custom_config_rt.erl
index b56eb1afc..a6aac9b47 100644
--- a/inttest/t_custom_config/t_custom_config_rt.erl
+++ b/inttest/t_custom_config/t_custom_config_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(t_custom_config_rt).
 
 -compile(export_all).
diff --git a/inttest/tdeps1/tdeps1_rt.erl b/inttest/tdeps1/tdeps1_rt.erl
index a72cc832a..3591ec01e 100644
--- a/inttest/tdeps1/tdeps1_rt.erl
+++ b/inttest/tdeps1/tdeps1_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(tdeps1_rt).
 
 -compile(export_all).
diff --git a/inttest/tdeps2/tdeps2_rt.erl b/inttest/tdeps2/tdeps2_rt.erl
index 22f0abee1..97a24ce8d 100644
--- a/inttest/tdeps2/tdeps2_rt.erl
+++ b/inttest/tdeps2/tdeps2_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(tdeps2_rt).
 
 -compile(export_all).
diff --git a/inttest/tdeps3/tdeps3_rt.erl b/inttest/tdeps3/tdeps3_rt.erl
index da87d439f..f56b3caed 100644
--- a/inttest/tdeps3/tdeps3_rt.erl
+++ b/inttest/tdeps3/tdeps3_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(tdeps3_rt).
 
 -compile(export_all).
diff --git a/inttest/tdeps_update/tdeps_update_rt.erl b/inttest/tdeps_update/tdeps_update_rt.erl
index e182ae217..c53e253c6 100644
--- a/inttest/tdeps_update/tdeps_update_rt.erl
+++ b/inttest/tdeps_update/tdeps_update_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(tdeps_update_rt).
 
 -compile(export_all).
diff --git a/inttest/thooks/thooks_rt.erl b/inttest/thooks/thooks_rt.erl
index 52af9f5c3..3cca6bbc0 100644
--- a/inttest/thooks/thooks_rt.erl
+++ b/inttest/thooks/thooks_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(thooks_rt).
 
 -include_lib("eunit/include/eunit.hrl").
diff --git a/inttest/tplugins/tplugins_rt.erl b/inttest/tplugins/tplugins_rt.erl
index d6908ad71..997661b4d 100644
--- a/inttest/tplugins/tplugins_rt.erl
+++ b/inttest/tplugins/tplugins_rt.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(tplugins_rt).
 -compile(export_all).
 
diff --git a/test/rebar_require_vsn_tests.erl b/test/rebar_require_vsn_tests.erl
index ac0e85e95..a48758668 100644
--- a/test/rebar_require_vsn_tests.erl
+++ b/test/rebar_require_vsn_tests.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(rebar_require_vsn_tests).
 
 -compile(export_all).
diff --git a/test/rebar_xref_eunit.erl b/test/rebar_xref_eunit.erl
index 45ec28368..341fe2e11 100644
--- a/test/rebar_xref_eunit.erl
+++ b/test/rebar_xref_eunit.erl
@@ -1,3 +1,5 @@
+%% -*- erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ts=4 sw=4 et
 -module(rebar_xref_eunit).
 
 -compile(export_all).