diff --git a/.gitignore b/.gitignore
index b6e4761..56dd569 100644
--- a/.gitignore
+++ b/.gitignore
@@ -89,7 +89,7 @@ ipython_config.py
 #   However, in case of collaboration, if having platform-specific dependencies or dependencies
 #   having no cross-platform support, pipenv may install dependencies that don't work, or not
 #   install all needed dependencies.
-#Pipfile.lock
+Pipfile.lock
 
 # PEP 582; used by e.g. github.com/David-OConnor/pyflow
 __pypackages__/
@@ -127,3 +127,6 @@ dmypy.json
 
 # Pyre type checker
 .pyre/
+
+# Other
+.vscode/
diff --git a/README-ja.md b/README-ja.md
index f251488..6fb58e9 100644
--- a/README-ja.md
+++ b/README-ja.md
@@ -165,7 +165,7 @@ $ amplify-bench stats preset_20230803_223440.json
 | `variables` | `object`           | ジョブで使用可能な変数の定義 (Optional)     |
 | `imports`   | `array[string]`    | ユーザー定義の問題のファイルパス (Optional) |
 
-`variables` キーに与える変数定義は `jobs` 内で参照することが出来ます。この時、`$` から始まる文字列は変数名として扱われます。例えば次のように全ての問題に共通する設定を与えるときに有用です。
+ファイルの中の `$` から始まる文字列は変数名として扱われます。最初に実行時の環境変数によって展開され、その後 `variables` キーに与えた変数定義が `jobs` 内で参照されます。例えば次のように全ての問題に共通する設定を与えるときに有用です。
 
 ```yaml
 variables:
diff --git a/README.md b/README.md
index 26ebdeb..11bc395 100644
--- a/README.md
+++ b/README.md
@@ -165,7 +165,7 @@ A job set file consisted of JSON objects with the following keys. The schema of
 | `variables` | `object`           | definitions of variables used in `jobs` (Optional) |
 | `imports`   | `array[string]`    | User-defined problem file path (Optional)          |
 
-Variable definitions for the `variables` key can be referenced in `jobs`. A string starting with `$` is treated as a variable name. This is useful, for example, to specify a setting that is commonly used in multiple jobs
+Strings in the file that begin with `$` are treated as variable names. Variables are first expanded by the environment variables at runtime, then the variable definitions given in the `variables` key are referenced in `jobs`. This is useful, for example, to specify a setting that is commonly used in multiple jobs
 
 ```yaml
 variables:
diff --git a/setup.cfg b/setup.cfg
index edf5815..de3b086 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,6 +1,6 @@
 [metadata]
 name = amplify-bench
-version = 0.1.3
+version = 0.2.0
 author = Fixstars Corporation, Fixstars Amplify Corporation
 author_email = "Yoshiki Matsuda" <y_matsuda@fixstars.com>
 maintainer = Yoshiki Matsuda, Hiroki Kawahara, Kosuke Suzuki