diff --git a/README.md b/README.md
index 534ddb4..71a1ad5 100644
--- a/README.md
+++ b/README.md
@@ -54,7 +54,7 @@ cargo test
 * [x] Add namespace for variables
 * [x] Custom env name
 * [x] Support feature config and other meta directives
-* [ ] Add default value to env if env is not found
+* [x] Add default value to env if env is not found
 * [ ] Concat env variables to one variable
 
 
diff --git a/examples/rocket/src/main.rs b/examples/rocket/src/main.rs
index 684d5cb..7770874 100644
--- a/examples/rocket/src/main.rs
+++ b/examples/rocket/src/main.rs
@@ -10,7 +10,7 @@ use rocket::config::{Config, Environment};
 config! {
     ROCKET {
         HOST: String => "localhost".to_string(),
-        PORT: u16 => 8000,
+        PORT: u16 => 9000,
         BASE_URL: String => "/".to_string(),
     }
 }
@@ -24,13 +24,7 @@ fn index() -> &'static str {
 fn main() {
     cfg::init();
 
-    let config = Config::build(Environment::Staging)
-        .address(cfg::ROCKET::HOST())
-        .port(cfg::ROCKET::PORT())
-        .finalize()
-        .unwrap();
-
-    rocket::custom(config)
+    rocket::ignite()
         .mount(&cfg::ROCKET::BASE_URL(), routes![index])
         .launch();
 }
\ No newline at end of file
diff --git a/itconfig/Cargo.toml b/itconfig/Cargo.toml
index 8c4176c..68cf56e 100644
--- a/itconfig/Cargo.toml
+++ b/itconfig/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "itconfig"
-version = "0.5.2"
+version = "0.6.0"
 authors = ["Dmitriy Pleshevskiy <dmitriy@ideascup.me>"]
 description = "Easy build a configs from environment variables and use it in globally."
 categories = ["config", "web-programming"]
diff --git a/itconfig/README.md b/itconfig/README.md
index b77ac4e..a7c6cc7 100644
--- a/itconfig/README.md
+++ b/itconfig/README.md
@@ -44,7 +44,7 @@ fn main () {
 * [x] Add namespace for variables
 * [x] Custom env name
 * [x] Support feature config and other meta directives
-* [ ] Add default value to env if env is not found
+* [x] Add default value to env if env is not found
 * [ ] Concat env variables to one variable
 
 
diff --git a/itconfig/src/lib.rs b/itconfig/src/lib.rs
index 9f83715..7825335 100644
--- a/itconfig/src/lib.rs
+++ b/itconfig/src/lib.rs
@@ -557,15 +557,28 @@ macro_rules! __itconfig_variable {
 #[macro_export(local_inner_macro)]
 macro_rules! env_or {
     ($env_name:expr) => {
-        env_or!($env_name, panic!(format!(r#"Cannot read "{}" environment variable"#, $env_name)));
+        env_or!($env_name, format!(r#"Cannot read "{}" environment variable"#, $env_name), panic);
     };
 
-    ($env_name:expr, $default:expr) => {{
+    ($env_name:expr, $default:expr) => {
+        env_or!($env_name, $default, default);
+    };
+
+    ($env_name:expr, $default:expr, $token:tt) => {{
         use std::env;
         use itconfig::EnvValue;
         env::var($env_name)
             .map(|val| EnvValue::from(val).into())
-            .unwrap_or_else(|_| $default)
+            .unwrap_or_else(|_| env_or!(@$token $env_name, $default))
     }};
+
+    (@default $env_name:expr, $default:expr) => {{
+        env::set_var($env_name, $default.to_string());
+        $default
+    }};
+
+    (@panic $env_name:expr, $default:expr) => {
+        panic!($default);
+    };
 }
 
diff --git a/itconfig_tests/tests/config_macro.rs b/itconfig_tests/tests/config_macro.rs
index c3881a0..00c16df 100644
--- a/itconfig_tests/tests/config_macro.rs
+++ b/itconfig_tests/tests/config_macro.rs
@@ -240,4 +240,22 @@ fn stranger_meta_data() {
     #[cfg(feature = "postgres")]
     assert_eq!(cfg::DATABASE_URL(), "95");
     env::remove_var("MY_CUSTOM_NAME");
-}
\ No newline at end of file
+}
+
+#[test]
+fn setting_default_env_variable() {
+    config! {
+        DEFAULT_ENV_STRING: String => "localhost".to_string(),
+        DEFAULT_ENV_BOOLEAN: bool => true,
+        DEFAULT_ENV_UINT: u32 => 40,
+        DEFAULT_ENV_FLOAT: f64 => 40.9,
+    }
+
+    cfg::init();
+
+    assert_eq!(env::var("DEFAULT_ENV_STRING"), Ok("localhost".to_string()));
+    assert_eq!(env::var("DEFAULT_ENV_BOOLEAN"), Ok("true".to_string()));
+    assert_eq!(env::var("DEFAULT_ENV_UINT"), Ok("40".to_string()));
+    assert_eq!(env::var("DEFAULT_ENV_FLOAT"), Ok("40.9".to_string()));
+}
+