diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9ec0dbee..e7117fde 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -111,6 +111,12 @@ jobs:
           GITHUB_SHA: ${{ github.sha }}
         run: bash tools/ci/architecture_guards.sh
 
+      - name: PR Size Guard (advisory)
+        if: github.event_name == 'pull_request'
+        env:
+          GITHUB_BASE_REF: ${{ github.base_ref }}
+        run: bash tools/ci/pr_size_guard.sh
+
       - name: Test Stability Guards
         run: bash tools/ci/test_stability_guards.sh
 
diff --git a/.github/workflows/weekly-release.yml b/.github/workflows/weekly-release.yml
new file mode 100644
index 00000000..860aa88d
--- /dev/null
+++ b/.github/workflows/weekly-release.yml
@@ -0,0 +1,104 @@
+name: weekly-release
+
+on:
+  # Every Friday at 15:00 UTC (23:00 CST)
+  schedule:
+    - cron: "0 15 * * 5"
+  workflow_dispatch:
+    inputs:
+      skip_ci_check:
+        description: "Skip CI green check (emergency release)"
+        type: boolean
+        default: false
+
+concurrency:
+  group: weekly-release
+  cancel-in-progress: false
+
+jobs:
+  weekly-tag:
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: dev
+          fetch-depth: 0
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Check for new commits since last tag
+        id: check
+        run: |
+          LAST_TAG=$(git tag --sort=-creatordate | head -1)
+          if [ -z "$LAST_TAG" ]; then
+            echo "No previous tags found. Will create baseline."
+            echo "has_changes=true" >> "$GITHUB_OUTPUT"
+            echo "version=v0.1.0" >> "$GITHUB_OUTPUT"
+          else
+            COMMITS_SINCE=$(git rev-list --count "${LAST_TAG}..HEAD")
+            echo "Commits since ${LAST_TAG}: ${COMMITS_SINCE}"
+            if [ "$COMMITS_SINCE" -eq 0 ]; then
+              echo "No new commits. Skipping."
+              echo "has_changes=false" >> "$GITHUB_OUTPUT"
+            else
+              # Bump patch version
+              CURRENT=$(echo "$LAST_TAG" | sed 's/^v//')
+              MAJOR=$(echo "$CURRENT" | cut -d. -f1)
+              MINOR=$(echo "$CURRENT" | cut -d. -f2)
+              PATCH=$(echo "$CURRENT" | cut -d. -f3)
+              NEW_PATCH=$((PATCH + 1))
+              echo "has_changes=true" >> "$GITHUB_OUTPUT"
+              echo "version=v${MAJOR}.${MINOR}.${NEW_PATCH}" >> "$GITHUB_OUTPUT"
+            fi
+          fi
+
+      - name: Verify CI is green on dev
+        if: steps.check.outputs.has_changes == 'true' && !inputs.skip_ci_check
+        run: |
+          # Check the latest commit on dev has passing status
+          STATUS=$(gh api repos/${{ github.repository }}/commits/dev/status --jq '.state' 2>/dev/null || echo "unknown")
+          if [ "$STATUS" != "success" ] && [ "$STATUS" != "unknown" ]; then
+            echo "::error::CI is not green on dev (status: ${STATUS}). Fix CI before releasing."
+            echo "::error::Use workflow_dispatch with skip_ci_check=true for emergency releases."
+            exit 1
+          fi
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Merge dev into master and tag
+        if: steps.check.outputs.has_changes == 'true'
+        run: |
+          VERSION="${{ steps.check.outputs.version }}"
+
+          git config user.name "github-actions[bot]"
+          git config user.email "github-actions[bot]@users.noreply.github.com"
+
+          git checkout master
+          git merge dev --no-edit --ff-only || {
+            echo "::error::Cannot fast-forward master to dev. Manual merge required."
+            exit 1
+          }
+
+          git tag -a "${VERSION}" -m "Weekly release ${VERSION}"
+          git push origin master --tags
+
+          echo "Tagged ${VERSION} on master."
+
+      - name: Create GitHub Release
+        if: steps.check.outputs.has_changes == 'true'
+        run: |
+          VERSION="${{ steps.check.outputs.version }}"
+          LAST_TAG=$(git tag --sort=-creatordate | sed -n '2p')
+
+          if [ -n "$LAST_TAG" ]; then
+            BODY=$(git log --oneline "${LAST_TAG}..${VERSION}" | head -30)
+          else
+            BODY="Baseline release."
+          fi
+
+          gh release create "${VERSION}" \
+            --title "${VERSION}" \
+            --notes "${BODY}" \
+            --target master
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/docs/decisions/0007-stream-forward.md b/docs/decisions/0007-stream-forward.md
index cfdcf799..3c1b2b6e 100644
--- a/docs/decisions/0007-stream-forward.md
+++ b/docs/decisions/0007-stream-forward.md
@@ -1,6 +1,3 @@
-<<<<<<<< HEAD:docs/history/2026-03/STREAM_FORWARD_ARCHITECTURE.md
-# Aevatar Stream Forward 架构说明
-========
 ---
 title: "Aevatar Stream Forward 架构说明（2026-02-22）"
 status: active
@@ -8,7 +5,6 @@ owner: eanzhao
 ---
 
 # Aevatar Stream Forward 架构说明（2026-02-22）
->>>>>>>> c20fc87ec173e49be645ea287f4bb54ecd975935:docs/decisions/0007-stream-forward.md
 
 > Last updated: 2026-04-03. Active runtime paths: `InMemory` (dev/test) and `Orleans` with `KafkaProvider` (production).
 
diff --git a/tools/ci/pr_size_guard.sh b/tools/ci/pr_size_guard.sh
new file mode 100755
index 00000000..6f7a903d
--- /dev/null
+++ b/tools/ci/pr_size_guard.sh
@@ -0,0 +1,69 @@
+#!/usr/bin/env bash
+# PR Size Guard — warns when a PR exceeds the file/LOC thresholds.
+# Runs in CI on pull_request events. Advisory only (does not block merge).
+#
+# Thresholds:
+#   FILES_THRESHOLD=30   (max changed files, excluding auto-generated)
+#   LOC_THRESHOLD=800    (max net lines changed)
+#
+# Auto-generated files excluded from count:
+#   *.Designer.cs, *.g.cs, **/obj/**, **/bin/**, **/*.pb.cs
+
+set -euo pipefail
+
+FILES_THRESHOLD="${PR_SIZE_FILES_THRESHOLD:-30}"
+LOC_THRESHOLD="${PR_SIZE_LOC_THRESHOLD:-800}"
+
+# Determine diff target
+if [[ -n "${GITHUB_BASE_REF:-}" ]]; then
+  git fetch --no-tags --depth=1 origin "${GITHUB_BASE_REF}" 2>/dev/null || true
+  DIFF_TARGET="origin/${GITHUB_BASE_REF}...HEAD"
+elif [[ -n "${1:-}" ]]; then
+  DIFF_TARGET="$1"
+else
+  DIFF_TARGET="origin/dev...HEAD"
+fi
+
+echo "PR Size Guard: comparing ${DIFF_TARGET}"
+echo "Thresholds: files=${FILES_THRESHOLD}, LOC=${LOC_THRESHOLD}"
+
+# Count changed files (excluding auto-generated)
+CHANGED_FILES=$(git diff --name-only "${DIFF_TARGET}" 2>/dev/null \
+  | grep -v '\.Designer\.cs$' \
+  | grep -v '\.g\.cs$' \
+  | grep -v '\.pb\.cs$' \
+  | grep -v '/obj/' \
+  | grep -v '/bin/' \
+  | wc -l | tr -d ' ')
+
+# Count net LOC changed
+STAT_LINE=$(git diff --stat "${DIFF_TARGET}" 2>/dev/null | tail -1)
+INSERTIONS=$(echo "${STAT_LINE}" | grep -oE '[0-9]+ insertion' | grep -oE '[0-9]+' || echo "0")
+DELETIONS=$(echo "${STAT_LINE}" | grep -oE '[0-9]+ deletion' | grep -oE '[0-9]+' || echo "0")
+NET_LOC=$(( INSERTIONS - DELETIONS ))
+# Use absolute value for comparison
+ABS_LOC=${NET_LOC#-}
+
+echo "Result: ${CHANGED_FILES} files changed, +${INSERTIONS}/-${DELETIONS} (net ${NET_LOC})"
+
+EXIT_CODE=0
+
+if [[ "${CHANGED_FILES}" -gt "${FILES_THRESHOLD}" ]]; then
+  echo ""
+  echo "::warning::PR exceeds file threshold: ${CHANGED_FILES} files changed (limit: ${FILES_THRESHOLD}). Consider splitting this PR."
+  EXIT_CODE=1
+fi
+
+if [[ "${ABS_LOC}" -gt "${LOC_THRESHOLD}" ]]; then
+  echo ""
+  echo "::warning::PR exceeds LOC threshold: ${ABS_LOC} net lines (limit: ${LOC_THRESHOLD}). Consider splitting this PR."
+  EXIT_CODE=1
+fi
+
+if [[ "${EXIT_CODE}" -eq 0 ]]; then
+  echo "PR size OK."
+fi
+
+# Advisory only — always exit 0 so we don't block merge.
+# To make this blocking, change the line below to: exit ${EXIT_CODE}
+exit 0
diff --git a/tools/ci/stale_branch_cleanup.sh b/tools/ci/stale_branch_cleanup.sh
new file mode 100755
index 00000000..678c2907
--- /dev/null
+++ b/tools/ci/stale_branch_cleanup.sh
@@ -0,0 +1,63 @@
+#!/usr/bin/env bash
+# Stale Branch Cleanup — deletes remote branches that are already merged into dev.
+# Safety: ONLY deletes branches whose commits are fully reachable from dev.
+# Protected branches (master, dev, main, release/*) are never deleted.
+#
+# Usage:
+#   bash tools/ci/stale_branch_cleanup.sh          # dry-run (default)
+#   bash tools/ci/stale_branch_cleanup.sh --apply   # actually delete
+
+set -euo pipefail
+
+DRY_RUN=true
+if [[ "${1:-}" == "--apply" ]]; then
+  DRY_RUN=false
+fi
+
+TARGET_BRANCH="${CLEANUP_TARGET_BRANCH:-dev}"
+
+echo "Stale Branch Cleanup"
+echo "Target: origin/${TARGET_BRANCH}"
+echo "Mode: $(${DRY_RUN} && echo 'DRY RUN' || echo 'APPLY')"
+echo ""
+
+git fetch --prune origin 2>/dev/null || true
+
+# Protected branch patterns — never delete these
+PROTECTED_PATTERN="^origin/(master|dev|main|release/)"
+
+MERGED_BRANCHES=$(git branch -r --merged "origin/${TARGET_BRANCH}" 2>/dev/null \
+  | sed 's/^ *//' \
+  | grep '^origin/' \
+  | grep -v "origin/HEAD" \
+  | grep -Ev "${PROTECTED_PATTERN}" \
+  || true)
+
+if [[ -z "${MERGED_BRANCHES}" ]]; then
+  echo "No stale merged branches found."
+  exit 0
+fi
+
+COUNT=$(echo "${MERGED_BRANCHES}" | wc -l | tr -d ' ')
+echo "Found ${COUNT} merged branches:"
+echo ""
+
+while IFS= read -r branch; do
+  REMOTE_NAME="${branch#origin/}"
+  LAST_COMMIT_DATE=$(git log -1 --format="%ai" "${branch}" 2>/dev/null | cut -d' ' -f1)
+  LAST_AUTHOR=$(git log -1 --format="%an" "${branch}" 2>/dev/null)
+
+  if ${DRY_RUN}; then
+    echo "  [DRY RUN] would delete: ${REMOTE_NAME} (last: ${LAST_COMMIT_DATE} by ${LAST_AUTHOR})"
+  else
+    echo "  Deleting: ${REMOTE_NAME} (last: ${LAST_COMMIT_DATE} by ${LAST_AUTHOR})"
+    git push origin --delete "${REMOTE_NAME}" 2>/dev/null || echo "    Failed to delete ${REMOTE_NAME}"
+  fi
+done <<< "${MERGED_BRANCHES}"
+
+echo ""
+if ${DRY_RUN}; then
+  echo "Dry run complete. Run with --apply to delete."
+else
+  echo "Cleanup complete. ${COUNT} branches deleted."
+fi