diff --git a/AGENTS.md b/AGENTS.md
index 6de19cb9..12dea04b 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -96,6 +96,11 @@ Exceptions are allowed for migration and package-helper scripts where the helper
 - Do not add `aliases` to new menu entries. Aliases are reserved for
   established alternate names users already type, kept for compatibility.
 
+# Region
+
+- `/etc/omarchy/region` holds the region the installer derived from the timezone (`cn`); no file means Global. The profile lives in `default/regions/cn/`, its contract in `docs/regions.md`.
+- `install/config/region.sh` links the `cn` developer mirrors into `/etc` and `/.cargo` and refuses to replace a regular file it did not create.
+
 # Config Structure
 
 - `config/` - default configs copied to `~/.config/`
diff --git a/default/regions/cn/cargo.toml b/default/regions/cn/cargo.toml
new file mode 100644
index 00000000..5b56b114
--- /dev/null
+++ b/default/regions/cn/cargo.toml
@@ -0,0 +1,5 @@
+[source.crates-io]
+replace-with = "aliyun"
+
+[source.aliyun]
+registry = "sparse+https://mirrors.aliyun.com/crates.io-index/"
diff --git a/default/regions/cn/environment.conf b/default/regions/cn/environment.conf
new file mode 100644
index 00000000..60905de2
--- /dev/null
+++ b/default/regions/cn/environment.conf
@@ -0,0 +1,8 @@
+NPM_CONFIG_REGISTRY=https://registry.npmmirror.com
+PIP_INDEX_URL=https://mirrors.aliyun.com/pypi/simple/
+UV_DEFAULT_INDEX=https://mirrors.aliyun.com/pypi/simple/
+GOPROXY=https://mirrors.aliyun.com/goproxy/,direct
+RUSTUP_DIST_SERVER=https://mirrors.aliyun.com/rustup
+RUSTUP_UPDATE_ROOT=https://mirrors.aliyun.com/rustup/rustup
+BUNDLE_MIRROR__ALL=https://mirrors.aliyun.com/rubygems/
+MAVEN_ARGS=--global-settings /usr/share/omarchy/default/regions/cn/maven-settings.xml
diff --git a/default/regions/cn/gemrc b/default/regions/cn/gemrc
new file mode 100644
index 00000000..145984f2
--- /dev/null
+++ b/default/regions/cn/gemrc
@@ -0,0 +1,3 @@
+---
+:sources:
+- https://mirrors.aliyun.com/rubygems/
diff --git a/default/regions/cn/maven-settings.xml b/default/regions/cn/maven-settings.xml
new file mode 100644
index 00000000..5066b6bd
--- /dev/null
+++ b/default/regions/cn/maven-settings.xml
@@ -0,0 +1,9 @@
+<settings>
+  <mirrors>
+    <mirror>
+      <id>aliyun</id>
+      <mirrorOf>central</mirrorOf>
+      <url>https://maven.aliyun.com/repository/public</url>
+    </mirror>
+  </mirrors>
+</settings>
diff --git a/docs/regions.md b/docs/regions.md
index 23858f37..e64d89c0 100644
--- a/docs/regions.md
+++ b/docs/regions.md
@@ -34,7 +34,11 @@ For China, the builder installs `archlinuxcn-keyring` using the existing Arch tr
 
 ## Scope of the China profile
 
-The China profile provides repository defaults only. Language is a separate installer choice, not part of a region: a Chinese speaker outside China keeps global mirrors, and a China install in English still gets the regional ones.
+The China profile provides repository defaults and developer mirrors. Language is a separate installer choice, not part of a region: a Chinese speaker outside China keeps global mirrors, and a China install in English still gets the regional ones.
+
+## Developer mirrors
+
+The `cn` profile also points the common package managers at mirrors inside China: `environment.conf` (npm, PyPI and uv, Go, rustup, Bundler, and Maven through `MAVEN_ARGS`), `cargo.toml` for crates.io, `gemrc` for RubyGems, and `maven-settings.xml`, which Maven reads in place. During installation `install/config/region.sh` links the first three to `/etc/environment.d/90-omarchy-china.conf`, `/.cargo/config.toml` and `/etc/gemrc` when the marker says `cn`. It refuses to replace a regular file it did not create. The environment reaches sessions started after login.
 
 ## Remaining release validation
 
diff --git a/install/config/all.sh b/install/config/all.sh
index a221a398..3b5655a9 100644
--- a/install/config/all.sh
+++ b/install/config/all.sh
@@ -1,3 +1,4 @@
+run_logged "$OMARCHY_INSTALL/config/region.sh"
 run_logged "$OMARCHY_INSTALL/config/theme-system.sh"
 run_logged "$OMARCHY_INSTALL/config/browser-policy.sh"
 run_logged "$OMARCHY_INSTALL/config/increase-lockout-limit.sh"
diff --git a/install/config/region.sh b/install/config/region.sh
new file mode 100644
index 00000000..a009c123
--- /dev/null
+++ b/install/config/region.sh
@@ -0,0 +1,33 @@
+cn_links=(
+  "environment.conf /etc/environment.d/90-omarchy-china.conf"
+  "cargo.toml /.cargo/config.toml"
+  "gemrc /etc/gemrc"
+)
+
+# The installer writes the marker from the timezone.
+region=global
+if [[ -e /etc/omarchy/region ]]; then
+  region=$(</etc/omarchy/region)
+fi
+
+case $region in
+global) ;;
+cn)
+  for link in "${cn_links[@]}"; do
+    read -r _ target <<<"$link"
+    if [[ -e $target && ! -L $target ]]; then
+      echo "Refusing to replace $target, which Omarchy did not create" >&2
+      exit 1
+    fi
+  done
+  for link in "${cn_links[@]}"; do
+    read -r source target <<<"$link"
+    mkdir -p "${target%/*}"
+    ln -sfn "$OMARCHY_PATH/default/regions/cn/$source" "$target"
+  done
+  ;;
+*)
+  echo "Unknown region: $region" >&2
+  exit 1
+  ;;
+esac
diff --git a/test/shell.d/region-test.sh b/test/shell.d/region-test.sh
new file mode 100644
index 00000000..ef638034
--- /dev/null
+++ b/test/shell.d/region-test.sh
@@ -0,0 +1,47 @@
+#!/bin/bash
+
+set -euo pipefail
+
+source "$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)/base-test.sh"
+
+test_tmp=$(mktemp -d)
+trap 'rm -rf "$test_tmp"' EXIT
+
+region_setup="$test_tmp/region.sh"
+root="$test_tmp/root"
+sed -e "s|/etc/|$root/etc/|g" -e "s| /\.cargo/| $root/.cargo/|g" "$ROOT/install/config/region.sh" >"$region_setup"
+export OMARCHY_PATH="$ROOT"
+mkdir -p "$root/etc/omarchy"
+
+bash -e "$region_setup"
+[[ -z $(find "$root" -type l) ]] || fail "no marker links nothing"
+pass "no marker installs Global"
+
+echo cn >"$root/etc/omarchy/region"
+bash -e "$region_setup"
+for link in "environment.conf etc/environment.d/90-omarchy-china.conf" "cargo.toml .cargo/config.toml" "gemrc etc/gemrc"; do
+  read -r source target <<<"$link"
+  [[ $(readlink "$root/$target") == "$ROOT/default/regions/cn/$source" ]] || fail "China links /$target to the shipped $source"
+done
+bash -e "$region_setup"
+pass "the cn marker links the developer mirror drop-ins, again without error"
+
+rm "$root/etc/gemrc"
+echo ":sources: []" >"$root/etc/gemrc"
+if output=$(bash -e "$region_setup" 2>&1); then
+  fail "China refuses to replace an admin's /etc/gemrc" "$output"
+fi
+[[ $output == "Refusing to replace $root/etc/gemrc, which Omarchy did not create" && $(<"$root/etc/gemrc") == ":sources: []" ]] ||
+  fail "China names the file it refuses to replace and leaves it" "$output"
+rm "$root/etc/gemrc"
+pass "region setup never replaces mirror config Omarchy did not create"
+
+echo mars >"$root/etc/omarchy/region"
+if output=$(bash -e "$region_setup" 2>&1); then
+  fail "an unknown region fails" "$output"
+fi
+[[ $output == "Unknown region: mars" ]] || fail "region setup names the unknown region" "$output"
+pass "region setup rejects an unknown region"
+
+grep -qx 'run_logged "$OMARCHY_INSTALL/config/region.sh"' "$ROOT/install/config/all.sh" || fail "the install runs region setup"
+pass "the install runs region setup"