diff --git a/.github/workflows/sdk-java.yml b/.github/workflows/sdk-java.yml
index 071c522bcf7..61799ee961f 100644
--- a/.github/workflows/sdk-java.yml
+++ b/.github/workflows/sdk-java.yml
@@ -41,10 +41,18 @@ on:
 permissions:
   contents: 'read'
 
+env:
+  MAVEN_VERSION: '3.9.11'
+  MAVEN_SHA512: 'bcfe4fe305c962ace56ac7b5fc7a08b87d5abd8b7e89027ab251069faebee516b0ded8961445d6d91ec1985dfe30f8153268843c89aa392733d1a3ec956c9978'
+
+concurrency:
+  group: 'sdk-java-${{ github.event.pull_request.number || github.run_id }}'
+  cancel-in-progress: true
+
 jobs:
   test:
     name: '${{ matrix.os }} / Java ${{ matrix.java }}'
-    runs-on: '${{ matrix.os }}'
+    runs-on: '${{ (matrix.os == ''ubuntu-latest'' && github.repository == ''QwenLM/qwen-code'' && vars.MAINTAINER_ECS_RUNNER_DISABLED != ''true'' && (github.event_name == ''push'' || github.event.pull_request.head.repo.full_name == github.repository)) && fromJSON(''["self-hosted", "linux", "x64", "ecs-qwen"]'') || matrix.os }}'
     timeout-minutes: 30
     strategy:
       fail-fast: false
@@ -61,8 +69,32 @@ jobs:
           - os: 'windows-latest'
             java: '21'
     steps:
+      - name: 'Restore workspace ownership'
+        if: "${{ runner.environment == 'self-hosted' }}"
+        run: |-
+          set -uo pipefail
+          RUNNER_UID="$(id -u)"
+          RUNNER_GID="$(id -g)"
+          if [ "$RUNNER_UID" != "0" ]; then
+            chown -R "$RUNNER_UID:$RUNNER_GID" "$GITHUB_WORKSPACE" 2>/dev/null || sudo -n chown -R "$RUNNER_UID:$RUNNER_GID" "$GITHUB_WORKSPACE" || echo "::warning::could not restore workspace ownership; checkout may fail on leftover root-owned files"
+          fi
+          chmod -R u+rwX "$GITHUB_WORKSPACE" 2>/dev/null || sudo -n chmod -R u+rwX "$GITHUB_WORKSPACE" || echo "::warning::could not restore workspace write permissions; checkout may fail on leftover read-only files"
+
       - name: 'Checkout'
         uses: 'actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10' # v6.0.3
+        with:
+          ref: "${{ (runner.environment == 'self-hosted' && github.event_name == 'pull_request' && format('refs/pull/{0}/head', github.event.pull_request.number)) || github.ref }}"
+
+      - name: 'Verify checkout includes expected head commit'
+        if: "${{ runner.environment == 'self-hosted' && github.event_name == 'pull_request' }}"
+        env:
+          EXPECTED_SHA: '${{ github.event.pull_request.head.sha }}'
+        run: |-
+          if ! git merge-base --is-ancestor "${EXPECTED_SHA}" HEAD; then
+            echo "::error::Checked out ref does not contain expected head ${EXPECTED_SHA}."
+            git log --oneline --decorate -5
+            exit 1
+          fi
 
       - name: 'Set up Java'
         uses: 'actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654' # v5.2.0
@@ -72,6 +104,15 @@ jobs:
           cache: 'maven'
           cache-dependency-path: 'packages/sdk-java/qwencode/pom.xml'
 
+      - name: 'Set up Maven (self-hosted)'
+        if: "${{ runner.environment == 'self-hosted' }}"
+        run: |-
+          archive="${RUNNER_TEMP}/apache-maven-${MAVEN_VERSION}-bin.tar.gz"
+          curl -fsSL "https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/${MAVEN_VERSION}/apache-maven-${MAVEN_VERSION}-bin.tar.gz" -o "${archive}"
+          echo "${MAVEN_SHA512}  ${archive}" | sha512sum --check --status
+          tar -xzf "${archive}" -C "${RUNNER_TEMP}"
+          echo "${RUNNER_TEMP}/apache-maven-${MAVEN_VERSION}/bin" >> "${GITHUB_PATH}"
+
       - name: 'Run Java SDK tests'
         working-directory: 'packages/sdk-java/qwencode'
         run: 'mvn --batch-mode --no-transfer-progress clean test'
@@ -88,18 +129,56 @@ jobs:
 
   daemon-e2e:
     name: 'Real daemon E2E / Java 11'
-    runs-on: 'ubuntu-latest'
+    runs-on: '${{ (github.repository == ''QwenLM/qwen-code'' && vars.MAINTAINER_ECS_RUNNER_DISABLED != ''true'' && (github.event_name == ''push'' || github.event.pull_request.head.repo.full_name == github.repository)) && fromJSON(''["self-hosted", "linux", "x64", "ecs-qwen"]'') || ''ubuntu-latest'' }}'
     timeout-minutes: 30
     steps:
+      - name: 'Restore workspace ownership'
+        if: "${{ runner.environment == 'self-hosted' }}"
+        run: |-
+          set -uo pipefail
+          RUNNER_UID="$(id -u)"
+          RUNNER_GID="$(id -g)"
+          if [ "$RUNNER_UID" != "0" ]; then
+            chown -R "$RUNNER_UID:$RUNNER_GID" "$GITHUB_WORKSPACE" 2>/dev/null || sudo -n chown -R "$RUNNER_UID:$RUNNER_GID" "$GITHUB_WORKSPACE" || echo "::warning::could not restore workspace ownership; checkout may fail on leftover root-owned files"
+          fi
+          chmod -R u+rwX "$GITHUB_WORKSPACE" 2>/dev/null || sudo -n chmod -R u+rwX "$GITHUB_WORKSPACE" || echo "::warning::could not restore workspace write permissions; checkout may fail on leftover read-only files"
+
       - name: 'Checkout'
         uses: 'actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10' # v6.0.3
+        with:
+          ref: "${{ (runner.environment == 'self-hosted' && github.event_name == 'pull_request' && format('refs/pull/{0}/head', github.event.pull_request.number)) || github.ref }}"
 
-      - name: 'Set up Node.js'
+      - name: 'Verify checkout includes expected head commit'
+        if: "${{ runner.environment == 'self-hosted' && github.event_name == 'pull_request' }}"
+        env:
+          EXPECTED_SHA: '${{ github.event.pull_request.head.sha }}'
+        run: |-
+          if ! git merge-base --is-ancestor "${EXPECTED_SHA}" HEAD; then
+            echo "::error::Checked out ref does not contain expected head ${EXPECTED_SHA}."
+            git log --oneline --decorate -5
+            exit 1
+          fi
+
+      # Self-hosted can't reach nodejs.org reliably; reuse the machine's Node.
+      - name: 'Set up Node.js 22 (hosted)'
+        if: "${{ runner.environment == 'github-hosted' }}"
         uses: 'actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e' # v6.4.0
         with:
           node-version: '22'
           cache: 'npm'
 
+      - name: 'Use pre-installed Node.js (self-hosted)'
+        if: "${{ runner.environment == 'self-hosted' }}"
+        run: |-
+          if ! command -v node >/dev/null 2>&1; then
+            echo "::error::Node.js is not on PATH for this self-hosted runner. Provision Node 22.x or set MAINTAINER_ECS_RUNNER_DISABLED=true."
+            exit 1
+          fi
+          echo "Using pre-installed Node $(node -v) / npm $(npm -v)"
+          if [[ "$(node -p 'process.versions.node.split(".")[0]')" != "22" ]]; then
+            echo "::warning::Expected Node 22.x but found $(node -v); daemon E2E will run against the runner's Node."
+          fi
+
       - name: 'Set up Java'
         uses: 'actions/setup-java@be666c2fcd27ec809703dec50e508c2fdc7f6654' # v5.2.0
         with:
@@ -108,6 +187,15 @@ jobs:
           cache: 'maven'
           cache-dependency-path: 'packages/sdk-java/qwencode/pom.xml'
 
+      - name: 'Set up Maven (self-hosted)'
+        if: "${{ runner.environment == 'self-hosted' }}"
+        run: |-
+          archive="${RUNNER_TEMP}/apache-maven-${MAVEN_VERSION}-bin.tar.gz"
+          curl -fsSL "https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/${MAVEN_VERSION}/apache-maven-${MAVEN_VERSION}-bin.tar.gz" -o "${archive}"
+          echo "${MAVEN_SHA512}  ${archive}" | sha512sum --check --status
+          tar -xzf "${archive}" -C "${RUNNER_TEMP}"
+          echo "${RUNNER_TEMP}/apache-maven-${MAVEN_VERSION}/bin" >> "${GITHUB_PATH}"
+
       - name: 'Install Node.js dependencies'
         run: 'npm ci --prefer-offline --no-audit --progress=false'
 
diff --git a/scripts/run-java-daemon-sdk-e2e.ts b/scripts/run-java-daemon-sdk-e2e.ts
index d336e5344de..92f35786b64 100644
--- a/scripts/run-java-daemon-sdk-e2e.ts
+++ b/scripts/run-java-daemon-sdk-e2e.ts
@@ -131,7 +131,6 @@ const daemon = spawn(
 let stderr = '';
 let javaTest: ChildProcess | undefined;
 let receivedSignal: NodeJS.Signals | undefined;
-let succeeded = false;
 daemon.stderr?.on('data', (chunk) => {
   stderr += chunk.toString();
 });
@@ -297,7 +296,6 @@ try {
       'Java E2E completed without exercising the daemon model path; the integration tests may have been skipped',
     );
   }
-  succeeded = true;
 } catch (error) {
   runFailure = error;
 }
@@ -322,10 +320,14 @@ try {
 }
 process.off('SIGINT', handleSigint);
 process.off('SIGTERM', handleSigterm);
-if (succeeded && cleanupFailures.length === 0) {
-  rmSync(temporary, { recursive: true, force: true });
-} else {
+if (process.env.QWEN_DAEMON_E2E_KEEP_STATE === '1') {
   console.error(`Retained Java daemon E2E state at ${temporary}`);
+} else {
+  try {
+    rmSync(temporary, { recursive: true, force: true });
+  } catch (error) {
+    cleanupFailures.push(error);
+  }
 }
 if (receivedSignal !== undefined) {
   process.kill(process.pid, receivedSignal);
diff --git a/scripts/tests/sdk-java-workflow.test.js b/scripts/tests/sdk-java-workflow.test.js
new file mode 100644
index 00000000000..71fa309b50c
--- /dev/null
+++ b/scripts/tests/sdk-java-workflow.test.js
@@ -0,0 +1,27 @@
+import { readFileSync } from 'node:fs';
+import { describe, expect, it } from 'vitest';
+
+const workflow = readFileSync('.github/workflows/sdk-java.yml', 'utf8');
+const job = (name) => {
+  const start = workflow.indexOf(`  ${name}:`);
+  const next = workflow.slice(start + 1).search(/\n {2}[a-z0-9-]+:\n/);
+  return workflow.slice(start, next < 0 ? undefined : start + 1 + next);
+};
+
+describe('SDK Java self-hosted workflow guards', () => {
+  it.each(['test', 'daemon-e2e'])('protects the %s job', (name) => {
+    const block = job(name);
+    for (const fragment of [
+      "github.repository == ''QwenLM/qwen-code''",
+      'github.event.pull_request.head.repo.full_name == github.repository',
+      "vars.MAINTAINER_ECS_RUNNER_DISABLED != ''true''",
+      'fromJSON(\'\'["self-hosted", "linux", "x64", "ecs-qwen"]\'\')',
+      "format('refs/pull/{0}/head', github.event.pull_request.number)",
+      "EXPECTED_SHA: '${{ github.event.pull_request.head.sha }}'",
+      'git merge-base --is-ancestor "${EXPECTED_SHA}" HEAD',
+      'exit 1',
+    ]) {
+      expect(block).toContain(fragment);
+    }
+  });
+});