diff --git a/.debian/DEBIAN/control b/.debian/DEBIAN/control
index 38de25f..92f299a 100644
--- a/.debian/DEBIAN/control
+++ b/.debian/DEBIAN/control
@@ -1,5 +1,5 @@
 Package: wg-meta
-Version: 0.3.0
+Version: 0.3.1
 Section: base
 Priority: optional
 Architecture: all
diff --git a/CHANGES b/CHANGES
index 615ad24..86257cd 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,7 @@
+0.3.1 2021-07-06 Tobias Bossert (tobib at cpan.org)
+- Improved doc
+- fix: concurrency test -> added small delay between writes
+
 0.3.0 2021-07-03 Tobias Bossert (tobib at cpan.org)
 - changed: CLI: Seamless support for custom attributes (set and addpeer)
 - added: CLI: Ability to remove peers
diff --git a/VERSION b/VERSION
index 9325c3c..a2268e2 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.3.0
\ No newline at end of file
+0.3.1
\ No newline at end of file
diff --git a/bin/wg-meta b/bin/wg-meta
index 61a34f5..0081421 100755
--- a/bin/wg-meta
+++ b/bin/wg-meta
@@ -132,7 +132,7 @@ use experimental 'signatures';
 use Wireguard::WGmeta::Cli::Router;
 use Wireguard::WGmeta::Cli::TerminalHelpers;
 
-our $VERSION = "0.3.0";
+our $VERSION = "0.3.1";
 
 local $SIG{__WARN__} = sub($message) {
     prettify_message($message, 1);
diff --git a/lib/Wireguard/WGmeta.pm b/lib/Wireguard/WGmeta.pm
index 9574e4f..ea708bf 100644
--- a/lib/Wireguard/WGmeta.pm
+++ b/lib/Wireguard/WGmeta.pm
@@ -66,6 +66,6 @@ use strict;
 use warnings FATAL => 'all';
 package Wireguard::WGmeta;
 
-our $VERSION = "0.3.0"; # Do not change manually
+our $VERSION = "0.3.1"; # Do not change manually
 
 1;
diff --git a/lib/Wireguard/WGmeta/Cli/Router.pm b/lib/Wireguard/WGmeta/Cli/Router.pm
index 43bf73e..9ce0233 100644
--- a/lib/Wireguard/WGmeta/Cli/Router.pm
+++ b/lib/Wireguard/WGmeta/Cli/Router.pm
@@ -27,7 +27,7 @@ use Wireguard::WGmeta::Cli::Commands::Remove;
 use base 'Exporter';
 our @EXPORT = qw(route_command);
 
-our $VERSION = "0.3.0";
+our $VERSION = "0.3.1";
 
 =head2 route_command($ref_list_input_args)
 
diff --git a/lib/Wireguard/WGmeta/Parser/Conf.pm b/lib/Wireguard/WGmeta/Parser/Conf.pm
index a23a88a..1730585 100644
--- a/lib/Wireguard/WGmeta/Parser/Conf.pm
+++ b/lib/Wireguard/WGmeta/Parser/Conf.pm
@@ -44,7 +44,7 @@ use constant INTERNAL_KEY_PREFIX => 'int_';
 use base 'Exporter';
 our @EXPORT = qw(parse_raw_wg_config INTERNAL_KEY_PREFIX);
 
-our $VERSION = "0.3.0";
+our $VERSION = "0.3.1";
 
 =head3 parse_raw_wg_config($file_content, $on_every_value, $on_new_section [, $skip, $wg_meta_prefix, $wg_disabled_prefix])
 
diff --git a/lib/Wireguard/WGmeta/Parser/Middleware.pm b/lib/Wireguard/WGmeta/Parser/Middleware.pm
index 1650a22..d9797ca 100644
--- a/lib/Wireguard/WGmeta/Parser/Middleware.pm
+++ b/lib/Wireguard/WGmeta/Parser/Middleware.pm
@@ -36,7 +36,7 @@ use Wireguard::WGmeta::Utils;
 use base 'Exporter';
 our @EXPORT = qw(parse_wg_config2 create_wg_config2);
 
-our $VERSION = "0.3.0";
+our $VERSION = "0.3.1";
 
 =head3 parse_wg_config2($config_file_content, $interface_name [, $wg_meta_prefix, $disabled_prefix, $use_checksum])
 
diff --git a/lib/Wireguard/WGmeta/Parser/Show.pm b/lib/Wireguard/WGmeta/Parser/Show.pm
index 3def996..4f06c43 100644
--- a/lib/Wireguard/WGmeta/Parser/Show.pm
+++ b/lib/Wireguard/WGmeta/Parser/Show.pm
@@ -28,7 +28,7 @@ use experimental 'signatures';
 use base 'Exporter';
 our @EXPORT = qw(wg_show_dump_parser);
 
-our $VERSION = "0.3.0"; # do not change manually, this variable is updated when calling make
+our $VERSION = "0.3.1"; # do not change manually, this variable is updated when calling make
 
 
 =head3 wg_show_dump_parser($input)
diff --git a/lib/Wireguard/WGmeta/ValidAttributes.pm b/lib/Wireguard/WGmeta/ValidAttributes.pm
index 7ac5b31..ae27243 100644
--- a/lib/Wireguard/WGmeta/ValidAttributes.pm
+++ b/lib/Wireguard/WGmeta/ValidAttributes.pm
@@ -27,7 +27,7 @@ use experimental 'signatures';
 
 use Wireguard::WGmeta::Validator;
 
-our $VERSION = "0.3.0";
+our $VERSION = "0.3.1";
 
 =head1 ATTRIBUTE TYPES
 
diff --git a/lib/Wireguard/WGmeta/Wrapper/Config.pm b/lib/Wireguard/WGmeta/Wrapper/Config.pm
index b8ed75e..0abd0dd 100644
--- a/lib/Wireguard/WGmeta/Wrapper/Config.pm
+++ b/lib/Wireguard/WGmeta/Wrapper/Config.pm
@@ -50,7 +50,7 @@ use Wireguard::WGmeta::ValidAttributes;
 use Wireguard::WGmeta::Utils;
 use Wireguard::WGmeta::Parser::Conf qw(INTERNAL_KEY_PREFIX);
 
-our $VERSION = "0.3.0"; # do not change manually, this variable is updated when calling make
+our $VERSION = "0.3.1"; # do not change manually, this variable is updated when calling make
 
 use constant FALSE => 0;
 use constant TRUE => 1;
diff --git a/lib/Wireguard/WGmeta/Wrapper/ConfigT.pm b/lib/Wireguard/WGmeta/Wrapper/ConfigT.pm
index 2203fa5..7cee2d0 100644
--- a/lib/Wireguard/WGmeta/Wrapper/ConfigT.pm
+++ b/lib/Wireguard/WGmeta/Wrapper/ConfigT.pm
@@ -116,7 +116,7 @@ use constant FALSE => 0;
 use constant TRUE => 1;
 use constant INTEGRITY_HASH_SALT => 'wefnwioefh9032ur3';
 
-our $VERSION = "0.3.0"; # do not change manually, this variable is updated when calling make
+our $VERSION = "0.3.1"; # do not change manually, this variable is updated when calling make
 
 =head3 is_valid_interface($interface)
 
diff --git a/lib/Wireguard/WGmeta/Wrapper/Show.pm b/lib/Wireguard/WGmeta/Wrapper/Show.pm
index fa7fc1e..6e11968 100644
--- a/lib/Wireguard/WGmeta/Wrapper/Show.pm
+++ b/lib/Wireguard/WGmeta/Wrapper/Show.pm
@@ -34,7 +34,7 @@ use warnings FATAL => 'all';
 use experimental 'signatures';
 
 
-our $VERSION = "0.3.0";
+our $VERSION = "0.3.1";
 
 use constant FALSE => 0;
 use constant TRUE => 1;