diff --git a/.github/README.md b/.github/README.md
new file mode 100644
index 0000000..f3b59da
--- /dev/null
+++ b/.github/README.md
@@ -0,0 +1,36 @@
+# RT-Thread 关联兼容性 CI
+
+Env 仓库本身不包含 RT-Thread 源码，但 RT-Thread 会把本仓库安装到 `~/.env/tools/scripts`，再执行：
+
+- `source ~/.env/env.sh`
+- `scons --pyconfig-silent`
+- `pkgs --update` / `pkgs --list`
+- `scons`
+
+`.github/workflows/rt-thread-compat.yml` 用当前 Env 提交搭出同一套目录布局，再拉取 `RT-Thread/rt-thread`、`packages` 和 `sdk`，确认这条引用链不会被 Env 侧改动打断。兼容脚本位于 `.github/scripts/`，因为它们只服务于 GitHub Actions 及其本地复现。
+
+## 本地运行
+
+不要覆盖正在使用的 `~/.env`。可以在一次性 HOME 下运行：
+
+```sh
+export CI_HOME="$(mktemp -d)"
+export HOME="$CI_HOME"
+export RTT_ROOT=/path/to/rt-thread
+
+./.github/scripts/prepare_env_layout.sh "$(pwd)" "$HOME/.env" \
+    /path/to/packages /path/to/sdk
+./.github/scripts/rt_thread_compat.sh
+```
+
+兼容脚本会从 SDK 索引安装 `arm-none-eabi-gcc`，不需要手动设置 `RTT_EXEC_PATH`。脚本会编译这两个 BSP：
+
+- `bsp/qemu-vexpress-a9`
+- `bsp/stm32/stm32f407-rt-spark`
+
+## 检查范围
+
+- Env 单元测试（Python 3.8 / 3.12）
+- 从 SDK 索引安装 `arm-none-eabi-gcc`，并通过 Env 的 SDK 状态发现工具链
+- `qemu-vexpress-a9` 的静默配置、包更新和 ARM GCC 编译
+- `stm32/stm32f407-rt-spark` 的静默配置、包更新和 ARM GCC 编译
diff --git a/.github/scripts/prepare_env_layout.sh b/.github/scripts/prepare_env_layout.sh
new file mode 100755
index 0000000..61811fd
--- /dev/null
+++ b/.github/scripts/prepare_env_layout.sh
@@ -0,0 +1,71 @@
+#!/usr/bin/env bash
+# Create the ~/.env layout that RT-Thread CI and local builds expect, using
+# the Env source under test instead of cloning env master.
+
+set -euo pipefail
+
+usage() {
+    echo "Usage: $0 <env-source> [env-root] [packages-src] [sdk-src]" >&2
+    exit 2
+}
+
+if [ "${1:-}" = "" ]; then
+    usage
+fi
+
+ENV_SOURCE=$(cd -- "$1" && pwd)
+ENV_ROOT=${2:-${ENV_ROOT:-$HOME/.env}}
+PACKAGES_SRC=${3:-${PACKAGES_SRC:-}}
+SDK_SRC=${4:-${SDK_SRC:-}}
+PACKAGE_URL=${RTT_PACKAGE_URL:-https://github.com/RT-Thread/packages.git}
+SDK_URL=${RTT_SDK_URL:-https://github.com/RT-Thread/sdk.git}
+
+mkdir -p "$ENV_ROOT/local_pkgs" "$ENV_ROOT/packages" "$ENV_ROOT/tools"
+
+if [ -e "$ENV_ROOT/tools/scripts" ] || [ -L "$ENV_ROOT/tools/scripts" ]; then
+    echo "Refusing to replace existing Env scripts directory: $ENV_ROOT/tools/scripts" >&2
+    exit 1
+fi
+if [ -e "$ENV_ROOT/env.sh" ]; then
+    echo "Refusing to replace existing Env activation script: $ENV_ROOT/env.sh" >&2
+    exit 1
+fi
+if [ -e "$ENV_ROOT/packages/Kconfig" ]; then
+    echo "Refusing to replace existing packages Kconfig: $ENV_ROOT/packages/Kconfig" >&2
+    exit 1
+fi
+
+ln -s "$ENV_SOURCE" "$ENV_ROOT/tools/scripts"
+cp "$ENV_SOURCE/env.sh" "$ENV_ROOT/env.sh"
+
+link_or_clone() {
+    dest=$1
+    src=$2
+    url=$3
+    name=$4
+
+    if [ -d "$dest/.git" ] || [ -L "$dest" ]; then
+        echo "Using existing $name at $dest"
+        return 0
+    fi
+    if [ -e "$dest" ]; then
+        echo "Refusing to replace existing $name path: $dest" >&2
+        exit 1
+    fi
+    if [ -n "$src" ]; then
+        src=$(cd -- "$src" && pwd)
+        ln -s "$src" "$dest"
+        echo "Linked $name from $src"
+        return 0
+    fi
+    git clone --depth=1 "$url" "$dest"
+}
+
+link_or_clone "$ENV_ROOT/packages/packages" "$PACKAGES_SRC" "$PACKAGE_URL" "packages index"
+link_or_clone "$ENV_ROOT/packages/sdk" "$SDK_SRC" "$SDK_URL" "SDK index"
+
+printf 'source "$PKGS_DIR/packages/Kconfig"\n' > "$ENV_ROOT/packages/Kconfig"
+
+echo "Env layout ready:"
+echo "  ENV_ROOT=$ENV_ROOT"
+echo "  scripts=$ENV_ROOT/tools/scripts -> $ENV_SOURCE"
diff --git a/.github/scripts/rt_thread_compat.sh b/.github/scripts/rt_thread_compat.sh
new file mode 100755
index 0000000..6f6329d
--- /dev/null
+++ b/.github/scripts/rt_thread_compat.sh
@@ -0,0 +1,120 @@
+#!/usr/bin/env bash
+# Exercise the Env layout the same way RT-Thread CI does:
+# source env.sh, install the SDK toolchain, then configure, update packages,
+# and build RT-Thread BSPs.
+
+set -euo pipefail
+
+ENV_ROOT=${ENV_ROOT:-$HOME/.env}
+RTT_ROOT=${RTT_ROOT:?RTT_ROOT must point at an RT-Thread checkout}
+QEMU_BSP=${QEMU_BSP:-bsp/qemu-vexpress-a9}
+SPARK_BSP=${SPARK_BSP:-bsp/stm32/stm32f407-rt-spark}
+SDK_TOOLCHAIN_VERSION=${SDK_TOOLCHAIN_VERSION:-v13.2.rel1}
+
+fail() {
+    echo "::error::$1" >&2
+    exit 1
+}
+
+require_dir() {
+    [ -d "$1" ] || fail "missing directory: $1"
+}
+
+require_file() {
+    [ -f "$1" ] || fail "missing file: $1"
+}
+
+require_dir "$ENV_ROOT"
+require_file "$ENV_ROOT/env.sh"
+require_dir "$ENV_ROOT/tools/scripts"
+require_dir "$RTT_ROOT"
+require_file "$RTT_ROOT/$QEMU_BSP/Kconfig"
+require_file "$RTT_ROOT/$SPARK_BSP/Kconfig"
+
+export ENV_ROOT
+export ENV_VENV_AUTO_UPGRADE=${ENV_VENV_AUTO_UPGRADE:-1}
+export RTT_ROOT
+
+# shellcheck disable=SC1091
+. "$ENV_ROOT/env.sh"
+
+command -v python3 >/dev/null || fail "python3 is not on PATH after sourcing env.sh"
+command -v scons >/dev/null || fail "scons is not on PATH after sourcing env.sh"
+command -v pkgs >/dev/null || fail "pkgs is not on PATH after sourcing env.sh"
+command -v menuconfig >/dev/null || fail "menuconfig is not on PATH after sourcing env.sh"
+
+python3 -c 'import kconfiglib, requests, SCons' || fail "Env Python dependencies are missing after activation"
+
+if ! pkgs --printenv | grep -F "ENV_ROOT:$ENV_ROOT" >/dev/null; then
+    fail "pkgs --printenv did not report ENV_ROOT=$ENV_ROOT"
+fi
+if ! pkgs --printenv | grep -F "PKGS_ROOT:$ENV_ROOT/packages" >/dev/null; then
+    fail "pkgs --printenv did not report PKGS_ROOT=$ENV_ROOT/packages"
+fi
+
+python3 "$ENV_ROOT/tools/scripts/env.py" -v
+pkgs -h >/dev/null
+menuconfig -h >/dev/null
+
+case "$SDK_TOOLCHAIN_VERSION" in
+    v13.2.rel1)
+        sdk_version_symbol=V132REL1
+        ;;
+    v10.3)
+        sdk_version_symbol=V103
+        ;;
+    *)
+        fail "unsupported SDK ARM GCC version: $SDK_TOOLCHAIN_VERSION"
+        ;;
+esac
+
+sdk_config="$ENV_ROOT/tools/scripts/.config"
+printf '%s\n' \
+    'CONFIG_TARGET_FILE=""' \
+    'CONFIG_PKG_USING_ARM_NONE_EABI_GCC=y' \
+    'CONFIG_PKG_ARM_NONE_EABI_GCC_PATH="sdk/Linux/arm-none-eabi-gcc"' \
+    "CONFIG_PKG_USING_ARM_NONE_EABI_GCC_${sdk_version_symbol}=y" \
+    "CONFIG_PKG_ARM_NONE_EABI_GCC_VER=\"$SDK_TOOLCHAIN_VERSION\"" \
+    > "$sdk_config"
+
+echo "==> Install ARM GCC $SDK_TOOLCHAIN_VERSION from the SDK index"
+(
+    cd "$ENV_ROOT/tools/scripts"
+    pkgs --update-force
+    pkgs --list
+)
+
+sdk_toolchain_root="$ENV_ROOT/tools/scripts/packages/arm-none-eabi-gcc-$SDK_TOOLCHAIN_VERSION"
+if [ -z "$sdk_toolchain_root" ] || [ ! -x "$sdk_toolchain_root/bin/arm-none-eabi-gcc" ]; then
+    fail "SDK did not install arm-none-eabi-gcc"
+fi
+"$sdk_toolchain_root/bin/arm-none-eabi-gcc" --version
+
+if [ -f "$RTT_ROOT/tools/requirements.txt" ]; then
+    python3 -m pip install -r "$RTT_ROOT/tools/requirements.txt"
+fi
+
+run_bsp() {
+    bsp_rel=$1
+    bsp_dir="$RTT_ROOT/$bsp_rel"
+
+    echo "==> RT-Thread Env steps for $bsp_rel"
+    scons --pyconfig-silent -C "$bsp_dir"
+    require_file "$bsp_dir/.config"
+    require_file "$bsp_dir/rtconfig.h"
+
+    (
+        cd "$bsp_dir"
+        pkgs --update-force
+        pkgs --list
+    )
+    require_file "$bsp_dir/packages/SConscript"
+
+    echo "==> Build $bsp_rel"
+    scons -j"$(nproc)" -C "$bsp_dir"
+}
+
+run_bsp "$QEMU_BSP"
+run_bsp "$SPARK_BSP"
+
+echo "RT-Thread Env compatibility checks passed."
diff --git a/.github/workflows/rt-thread-compat.yml b/.github/workflows/rt-thread-compat.yml
new file mode 100644
index 0000000..6464e25
--- /dev/null
+++ b/.github/workflows/rt-thread-compat.yml
@@ -0,0 +1,104 @@
+name: RT-Thread Env Compatibility
+
+on:
+  push:
+    branches:
+      - master
+    paths-ignore:
+      - '**/README.md'
+      - '**/README.zh-CN.md'
+  pull_request:
+    branches:
+      - master
+    paths-ignore:
+      - '**/README.md'
+      - '**/README.zh-CN.md'
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
+
+env:
+  ENV_VENV_AUTO_UPGRADE: '1'
+
+jobs:
+  unit-tests:
+    name: Unit tests (${{ matrix.python-version }})
+    runs-on: ubuntu-22.04
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ['3.8', '3.12']
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install test dependencies
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install SCons requests psutil tqdm kconfiglib PyYAML
+
+      - name: Run Env unit tests
+        run: python -m unittest discover -s plugins/tests -t . -v
+
+  rt-thread-compat:
+    name: RT-Thread reference compatibility
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout Env
+        uses: actions/checkout@v4
+        with:
+          path: env
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.8'
+
+      - name: Install host build packages
+        run: sudo apt-get update && sudo apt-get -qq install -y git python3-venv
+
+      - name: Checkout RT-Thread
+        uses: actions/checkout@v4
+        with:
+          repository: RT-Thread/rt-thread
+          path: rt-thread
+          fetch-depth: 1
+
+      - name: Checkout packages index
+        uses: actions/checkout@v4
+        with:
+          repository: RT-Thread/packages
+          path: packages-index
+          fetch-depth: 1
+
+      - name: Checkout SDK index
+        uses: actions/checkout@v4
+        with:
+          repository: RT-Thread/sdk
+          path: sdk-index
+          fetch-depth: 1
+
+      - name: Prepare Env layout used by RT-Thread
+        run: |
+          chmod +x env/.github/scripts/*.sh env/pkgs env/menuconfig env/sdk
+          env/.github/scripts/prepare_env_layout.sh \
+            "$GITHUB_WORKSPACE/env" \
+            "$HOME/.env" \
+            "$GITHUB_WORKSPACE/packages-index" \
+            "$GITHUB_WORKSPACE/sdk-index"
+
+      - name: Run RT-Thread compatibility checks
+        env:
+          RTT_ROOT: ${{ github.workspace }}/rt-thread
+        run: |
+          export ENV_ROOT="$HOME/.env"
+          env/.github/scripts/rt_thread_compat.sh
diff --git a/plugins/tests/test_env_venv.py b/plugins/tests/test_env_venv.py
index 6e1b993..ddc4dc8 100644
--- a/plugins/tests/test_env_venv.py
+++ b/plugins/tests/test_env_venv.py
@@ -195,11 +195,11 @@ def test_missing_package_is_repaired_without_upgrade_prompt(self):
         self.assertTrue(layout['rt_env'].is_file())
 
     def test_country_detection_and_explicit_index_override(self):
-        with mock.patch.object(env_venv, 'urlopen', return_value=FakeResponse(b'CN\n')) as request:
+        with mock.patch.object(env_venv, '_open_without_proxy', return_value=FakeResponse(b'CN\n')) as request:
             self.assertEqual(env_venv.detect_country(), 'CN')
         self.assertEqual(request.call_args[1]['timeout'], 3)
 
-        with mock.patch.object(env_venv, 'urlopen', side_effect=OSError('offline')):
+        with mock.patch.object(env_venv, '_open_without_proxy', side_effect=OSError('offline')):
             self.assertIsNone(env_venv.detect_country())
 
         output = io.StringIO()
diff --git a/plugins/tests/test_rt_thread_compat.py b/plugins/tests/test_rt_thread_compat.py
new file mode 100644
index 0000000..5d22539
--- /dev/null
+++ b/plugins/tests/test_rt_thread_compat.py
@@ -0,0 +1,27 @@
+import unittest
+from pathlib import Path
+
+
+REPOSITORY = Path(__file__).resolve().parents[2]
+
+
+class RtThreadCompatScriptTest(unittest.TestCase):
+    def test_compatibility_uses_the_sdk_toolchain_flow(self):
+        text = (REPOSITORY / '.github/scripts/rt_thread_compat.sh').read_text(encoding='utf-8')
+        self.assertIn('CONFIG_PKG_USING_ARM_NONE_EABI_GCC', text)
+        self.assertIn('pkgs --update-force', text)
+        self.assertIn('arm-none-eabi-gcc-$SDK_TOOLCHAIN_VERSION', text)
+        self.assertNotIn('RTT_EXEC_PATH', text)
+        self.assertNotIn('/opt/', text)
+
+    def test_workflow_does_not_install_a_toolchain_outside_the_sdk(self):
+        text = (REPOSITORY / '.github/workflows/rt-thread-compat.yml').read_text(encoding='utf-8')
+        self.assertIn('Checkout SDK index', text)
+        self.assertNotIn('RTT_EXEC_PATH', text)
+        self.assertNotIn('/opt/', text)
+        self.assertNotIn('toolchains-ci/releases', text)
+
+    def test_compat_script_covers_qemu_and_rt_spark(self):
+        text = (REPOSITORY / '.github/scripts/rt_thread_compat.sh').read_text(encoding='utf-8')
+        self.assertIn('bsp/qemu-vexpress-a9', text)
+        self.assertIn('bsp/stm32/stm32f407-rt-spark', text)