diff --git a/.github/workflows/download_test.yml b/.github/workflows/download_test.yml
index 86f728d20..b7885ba09 100644
--- a/.github/workflows/download_test.yml
+++ b/.github/workflows/download_test.yml
@@ -8,9 +8,14 @@ on:
       - "Cargo.*"
       - "crates/download/**"
       - ".github/workflows/download_test.yml"
+
+env:
+  VERSION: "prerelease-latest"
+
 defaults:
   run:
     shell: bash
+
 jobs:
   download-releases:
     strategy:
@@ -19,7 +24,7 @@ jobs:
         include:
           - name: 通常ダウンロード
             os: windows-latest
-            download_command: cargo run -vv -p download
+            download_command: cargo run -vv -p download -- # バージョン指定のために -- が必要
             download_dir: voicevox_core
             check_items: |
               voicevox_core.dll
@@ -169,29 +174,28 @@ jobs:
               open_jtalk_dic_utf_8-1.11
     runs-on: ${{ matrix.os }}
     name: ${{ matrix.name }}-${{ matrix.os }}
-    env:
-      EXPECTED_VOICEVOX_CORE_VERSION: latest
-      # See https://github.com/VOICEVOX/voicevox_core/issues/310
-      #EXPECTED_VOICEVOX_CORE_VERSION: ${{ matrix.expected_version || 'latest' }}
     steps:
       - uses: actions/checkout@v3
       - name: Set up Rust
-        if: ${{ startsWith(matrix.download_command, 'cargo ') }}
         uses: ./.github/actions/rust-toolchain-from-file
+      - name: Get prerelease latest version
+        if: ${{ env.VERSION == 'prerelease-latest' }}
+        run: |
+          VERSION=$(
+            curl -sSf https://api.github.com/repos/VOICEVOX/voicevox_core/releases \
+              -H 'authorization: Bearer ${{ github.token }}' \
+              -H 'content-type: application/json' |
+            jq -er '.[0].tag_name'
+          )
+          echo "VERSION=$VERSION" >> "$GITHUB_ENV"
       - name: Execute download command
-        run: ${{ matrix.download_command }}
+        run: ${{ matrix.download_command }} --version ${{ env.VERSION }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-      - name: Get latest version
-        if: ${{ env.EXPECTED_VOICEVOX_CORE_VERSION == 'latest' }}
-        run: |
-          echo "EXPECTED_VOICEVOX_CORE_VERSION=$(gh release view --repo VOICEVOX/voicevox_core --json 'tagName' --jq '.tagName')" >> "$GITHUB_ENV"
-        env:
-          GITHUB_TOKEN: ${{ github.token }}
       - name: Check downloaded version
         run: |
           [ -e "${{ matrix.download_dir }}/VERSION" ]
-          [ "$(cat "${{ matrix.download_dir }}/VERSION")" = "${{ env.EXPECTED_VOICEVOX_CORE_VERSION }}" ]
+          [ "$(cat "${{ matrix.download_dir }}/VERSION")" = "${{ env.VERSION }}" ]
       - name: Check downloaded files
         run: |
           mapfile -t items < <(echo -n '${{ matrix.check_items }}')
diff --git a/.github/workflows/java_lint.yml b/.github/workflows/java_lint.yml
new file mode 100644
index 000000000..b631819b8
--- /dev/null
+++ b/.github/workflows/java_lint.yml
@@ -0,0 +1,31 @@
+name: "Lint Java code"
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    paths:
+      - ./crates/voicevox_core_java_api/**/*.java
+      - ./crates/voicevox_core_java_api/gradle/**
+      - ./crates/voicevox_core_java_api/gradlew
+      - ./crates/voicevox_core_java_api/settings.gradle
+      - ./.github/workflows/java_lint.yml
+
+defaults:
+  run:
+    shell: bash
+    working-directory: ./crates/voicevox_core_java_api
+
+jobs:
+  java-lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-java@v2
+        with:
+          java-version: "11"
+          distribution: "adopt"
+      - name: Check code style
+        run: |
+          ./gradlew spotlessCheck --info
diff --git a/.github/workflows/python_lint.yml b/.github/workflows/python_lint.yml
new file mode 100644
index 000000000..c12b256cf
--- /dev/null
+++ b/.github/workflows/python_lint.yml
@@ -0,0 +1,40 @@
+name: "Lint Python code"
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    paths:
+      - ./example/python/**/*.py
+      - ./crates/voicevox_core_python_api/**/*.py
+      - ./crates/voicevox_core_python_api/requirements*.txt
+      - ./crates/voicevox_core_python_api/pyproject.toml
+      - ./.github/workflows/python_lint.yml
+
+defaults:
+  run:
+    shell: bash
+    working-directory: ./crates/voicevox_core_python_api
+
+jobs:
+  python:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-python@v4
+        with:
+          python-version: "3.8"
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -r requirements-dev.txt
+      - name: Check code style for voicevox_core_python_api
+        run: |
+          black --check .
+          isort --check .
+      - name: Check code style for example/python
+        working-directory: ./example/python
+        run: |
+          black --check .
+          isort --check .
diff --git a/crates/download/src/main.rs b/crates/download/src/main.rs
index fba1bc342..e52ca45f2 100644
--- a/crates/download/src/main.rs
+++ b/crates/download/src/main.rs
@@ -53,15 +53,15 @@ struct Args {
     min: bool,
 
     /// 出力先の指定
-    #[arg(short, long, default_value(DEFAULT_OUTPUT))]
+    #[arg(short, long, value_name("DIRECTORY"), default_value(DEFAULT_OUTPUT))]
     output: PathBuf,
 
     /// ダウンロードするvoicevox_coreのバージョンの指定
-    #[arg(short, long, default_value("latest"))]
+    #[arg(short, long, value_name("GIT_TAG_OR_LATEST"), default_value("latest"))]
     version: String,
 
     /// 追加でダウンロードするライブラリのバージョン
-    #[arg(long, default_value("latest"))]
+    #[arg(long, value_name("GIT_TAG_OR_LATEST"), default_value("latest"))]
     additional_libraries_version: String,
 
     /// ダウンロードするデバイスを指定する(cudaはlinuxのみ)
diff --git a/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/VoiceModel.java b/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/VoiceModel.java
index 90e74f6d9..05c1a11b2 100644
--- a/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/VoiceModel.java
+++ b/crates/voicevox_core_java_api/lib/src/main/java/jp/hiroshiba/voicevoxcore/VoiceModel.java
@@ -48,25 +48,25 @@ public static class SpeakerMeta {
     @SerializedName("name")
     @Expose
     @Nonnull
-    final String name;
+    public final String name;
 
     /** 話者に属するスタイル。 */
     @SerializedName("styles")
     @Expose
     @Nonnull
-    final StyleMeta[] styles;
+    public final StyleMeta[] styles;
 
     /** 話者のUUID。 */
     @SerializedName("speaker_uuid")
     @Expose
     @Nonnull
-    final String speakerUuid;
+    public final String speakerUuid;
 
     /** 話者のバージョン。 */
     @SerializedName("version")
     @Expose
     @Nonnull
-    final String version;
+    public final String version;
 
     private SpeakerMeta() {
       // GSONからコンストラクトするため、このメソッドは呼ばれることは無い。
@@ -84,12 +84,12 @@ public static class StyleMeta {
     @SerializedName("name")
     @Expose
     @Nonnull
-    final String name;
+    public final String name;
 
     /** スタイルID。 */
     @SerializedName("id")
     @Expose
-    final int id;
+    public final int id;
 
     private StyleMeta() {
       this.name = "";
diff --git a/crates/voicevox_core_python_api/python/test/test_user_dict_load.py b/crates/voicevox_core_python_api/python/test/test_user_dict_load.py
index 8c506a50f..d9829e6da 100644
--- a/crates/voicevox_core_python_api/python/test/test_user_dict_load.py
+++ b/crates/voicevox_core_python_api/python/test/test_user_dict_load.py
@@ -2,8 +2,9 @@
 # AudioQueryのkanaを比較して変化するかどうかで判断する。
 
 from uuid import UUID
-import pytest
+
 import conftest  # noqa: F401
+import pytest
 import voicevox_core  # noqa: F401
 
 
diff --git a/crates/voicevox_core_python_api/python/test/test_user_dict_manipulate.py b/crates/voicevox_core_python_api/python/test/test_user_dict_manipulate.py
index c9bc2c454..f7902ea94 100644
--- a/crates/voicevox_core_python_api/python/test/test_user_dict_manipulate.py
+++ b/crates/voicevox_core_python_api/python/test/test_user_dict_manipulate.py
@@ -2,8 +2,9 @@
 # どのコードがどの操作を行っているかはコメントを参照。
 
 import os
-from uuid import UUID
 import tempfile
+from uuid import UUID
+
 import pytest
 import voicevox_core  # noqa: F401
 
diff --git a/crates/voicevox_core_python_api/python/voicevox_core/__init__.py b/crates/voicevox_core_python_api/python/voicevox_core/__init__.py
index f59f705dd..ce6245bfc 100644
--- a/crates/voicevox_core_python_api/python/voicevox_core/__init__.py
+++ b/crates/voicevox_core_python_api/python/voicevox_core/__init__.py
@@ -11,15 +11,15 @@
     UserDictWord,
     UserDictWordType,
 )
-from ._rust import (
-    __version__,
+from ._rust import (  # noqa: F401
     OpenJtalk,
     Synthesizer,
+    UserDict,
     VoiceModel,
     VoicevoxError,
-    UserDict,
+    __version__,
     supported_devices,
-)  # noqa: F401
+)
 
 __all__ = [
     "__version__",
diff --git a/crates/voicevox_core_python_api/python/voicevox_core/_models.py b/crates/voicevox_core_python_api/python/voicevox_core/_models.py
index b559100be..c1cd9ccca 100644
--- a/crates/voicevox_core_python_api/python/voicevox_core/_models.py
+++ b/crates/voicevox_core_python_api/python/voicevox_core/_models.py
@@ -4,7 +4,7 @@
 
 import pydantic
 
-from ._rust import _validate_pronunciation, _to_zenkaku
+from ._rust import _to_zenkaku, _validate_pronunciation
 
 
 @pydantic.dataclasses.dataclass
diff --git a/crates/voicevox_core_python_api/python/voicevox_core/_rust.pyi b/crates/voicevox_core_python_api/python/voicevox_core/_rust.pyi
index e9c700a91..324ea0117 100644
--- a/crates/voicevox_core_python_api/python/voicevox_core/_rust.pyi
+++ b/crates/voicevox_core_python_api/python/voicevox_core/_rust.pyi
@@ -1,5 +1,5 @@
 from pathlib import Path
-from typing import Dict, Final, List, Literal, Union, TYPE_CHECKING
+from typing import TYPE_CHECKING, Dict, Final, List, Literal, Union
 from uuid import UUID
 
 import numpy as np