diff --git a/.github/workflows/release-fast.yml b/.github/workflows/release-fast.yml
new file mode 100644
index 0000000..c43ab7f
--- /dev/null
+++ b/.github/workflows/release-fast.yml
@@ -0,0 +1,93 @@
+name: Release Fast
+
+on:
+  workflow_dispatch:
+    inputs:
+      reddb_version:
+        description: "Pinned RedDB release tag to smoke-package with"
+        required: true
+        default: "v1.11.0"
+
+permissions:
+  contents: read
+
+concurrency:
+  group: release-fast-${{ github.ref }}
+  cancel-in-progress: true
+
+env:
+  REDDB_VERSION: ${{ github.event.inputs.reddb_version }}
+
+jobs:
+  linux-deb:
+    name: linux-x86_64 deb smoke
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v7
+        with:
+          persist-credentials: false
+
+      - name: Linux system dependencies
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y \
+            libwebkit2gtk-4.1-dev libgtk-3-dev libayatana-appindicator3-dev \
+            librsvg2-dev build-essential curl wget file libssl-dev libxdo-dev \
+            clang mold
+
+      - uses: pnpm/action-setup@v6
+        with:
+          version: 10.33.3
+
+      - uses: actions/setup-node@v6
+        with:
+          node-version: "22"
+          cache: pnpm
+
+      - uses: oven-sh/setup-bun@v2
+        with:
+          bun-version: "1.3.14"
+
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          targets: x86_64-unknown-linux-gnu
+
+      - uses: swatinem/rust-cache@v2
+        with:
+          workspaces: "apps/desktop/src-tauri -> target"
+
+      - name: Install
+        run: pnpm install --frozen-lockfile
+
+      - name: Check RedDB sidecar release asset
+        run: node scripts/check-reddb-release-assets.mjs x86_64-unknown-linux-gnu
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Brand sync
+        run: pnpm brand:sync
+
+      - name: Brand icons
+        run: pnpm brand:icons
+
+      - name: Build core contract
+        run: pnpm --filter @red-request/core build
+
+      - name: Build engine sidecar
+        run: pnpm engine:build
+
+      - name: Provision RedDB sidecar
+        run: pnpm reddb:fetch
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          REDDB_TARGET: x86_64-unknown-linux-gnu
+
+      - name: Build Linux deb only
+        run: pnpm --filter @red-request/desktop tauri build --bundles deb
+
+      - name: Upload deb artifact
+        uses: actions/upload-artifact@v5
+        with:
+          name: red-request-linux-x86_64-deb
+          path: apps/desktop/src-tauri/target/release/bundle/deb/*.deb
+          if-no-files-found: error
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 4c65594..f21d950 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -26,8 +26,27 @@ env:
   NO_STRIP: "1"
 
 jobs:
+  preflight:
+    name: release preflight
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v7
+        with:
+          ref: ${{ github.event.inputs.tag || github.ref }}
+          persist-credentials: false
+
+      - uses: actions/setup-node@v6
+        with:
+          node-version: "22"
+
+      - name: Check RedDB sidecar release assets
+        run: node scripts/check-reddb-release-assets.mjs x86_64-unknown-linux-gnu x86_64-pc-windows-msvc
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
   build:
     name: ${{ matrix.label }}
+    needs: preflight
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
diff --git a/CLAUDE.md b/CLAUDE.md
index 442ec73..7d4e486 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -12,6 +12,8 @@
 - Prefer indexed lookups, single-pass loops, lazy or partial rendering, storage-side filtering, and realistic fixtures over speculative rewrites.
 - Add or update lightweight perf workloads when touching hot paths. Benchmarks can start non-blocking, but visible regressions should become hard to ignore.
 - For Rust/Tauri performance work, profile release builds before invasive changes; keep `cargo fmt`, Clippy, frame-pointer/debug-info profiling, LTO, allocator, and PGO decisions tied to evidence.
+- Use `Release Fast` for a Linux `.deb` packaging smoke test; keep `Release` as the full Linux/macOS/Windows publishing path. RedDB sidecar assets must pass preflight before spending matrix time.
+- Treat `lto`, `codegen-units`, `strip`, allocator swaps, and PGO as measured release-profile experiments. Avoid `target-cpu=native` for public binaries unless distribution compatibility is intentionally narrowed.
 
 ## Agent skills
 
diff --git a/package.json b/package.json
index 9eb0249..15f7a6f 100644
--- a/package.json
+++ b/package.json
@@ -14,6 +14,7 @@
     "desktop:dev": "pnpm brand:sync && pnpm --filter @red-request/core build && pnpm --filter @red-request/engine build && pnpm --filter @red-request/desktop tauri dev",
     "desktop:build": "pnpm brand:sync && pnpm brand:icons && pnpm --filter @red-request/core build && pnpm engine:build && pnpm --filter @red-request/desktop tauri build",
     "engine:build": "node scripts/build-engine.mjs",
+    "reddb:preflight": "node scripts/check-reddb-release-assets.mjs x86_64-unknown-linux-gnu x86_64-pc-windows-msvc",
     "reddb:sync": "node scripts/sync-reddb.mjs",
     "reddb:fetch": "node scripts/fetch-reddb.mjs",
     "reddb:migration-demo": "node scripts/reddb-migration-demo.mjs",
diff --git a/scripts/check-reddb-release-assets.mjs b/scripts/check-reddb-release-assets.mjs
new file mode 100644
index 0000000..96c9ff3
--- /dev/null
+++ b/scripts/check-reddb-release-assets.mjs
@@ -0,0 +1,87 @@
+#!/usr/bin/env node
+// Fast release preflight for the embedded RedDB sidecar.
+//
+// The desktop app cannot be packaged for Linux/Windows unless the pinned RedDB
+// release exposes the prebuilt `red-<os>-<arch>` assets that fetch-reddb.mjs
+// downloads. Check that up front so release jobs fail before runner setup,
+// dependency install, and Tauri packaging work.
+//
+//   REDDB_VERSION=v1.11.0 node scripts/check-reddb-release-assets.mjs \
+//     x86_64-unknown-linux-gnu x86_64-pc-windows-msvc
+import { env, exit } from "node:process";
+
+const REPO = "reddb-io/reddb";
+
+function assetName(triple) {
+  const [arch] = triple.split("-");
+  const os = triple.includes("linux")
+    ? "linux"
+    : triple.includes("darwin")
+      ? "darwin"
+      : triple.includes("windows")
+        ? "windows"
+        : null;
+  if (!os) throw new Error(`unsupported target triple: ${triple}`);
+  const ext = os === "windows" ? ".exe" : "";
+  return `red-${os}-${arch}${ext}`;
+}
+
+async function ghJson(path) {
+  const controller = new AbortController();
+  const timeout = setTimeout(() => controller.abort(), 30_000);
+  const headers = {
+    Accept: "application/vnd.github+json",
+    "User-Agent": "red-request-reddb-preflight",
+  };
+  if (env.GITHUB_TOKEN) headers.Authorization = `Bearer ${env.GITHUB_TOKEN}`;
+  try {
+    const res = await fetch(`https://api.github.com/${path}`, {
+      headers,
+      signal: controller.signal,
+    });
+    if (!res.ok) throw new Error(`${path} -> ${res.status} ${res.statusText}`);
+    return res.json();
+  } finally {
+    clearTimeout(timeout);
+  }
+}
+
+const targets = process.argv.slice(2);
+if (targets.length === 0) {
+  console.error("usage: check-reddb-release-assets.mjs <target-triple> [...]");
+  exit(2);
+}
+
+const required = targets.map(assetName);
+const tag = env.REDDB_VERSION;
+
+let release;
+try {
+  release = tag
+    ? await ghJson(`repos/${REPO}/releases/tags/${encodeURIComponent(tag)}`)
+    : await ghJson(`repos/${REPO}/releases/latest`);
+} catch (err) {
+  console.error(`RedDB release preflight failed: ${err.message}`);
+  console.error(
+    "Publish the pinned RedDB release, fix REDDB_VERSION, or build the sidecar from source."
+  );
+  exit(1);
+}
+
+const available = new Set((release.assets ?? []).map((asset) => asset.name));
+const missing = required.filter((name) => !available.has(name));
+
+if (missing.length > 0) {
+  console.error(
+    `RedDB ${release.tag_name} is missing required release assets:`
+  );
+  for (const name of missing) console.error(`  - ${name}`);
+  console.error("");
+  console.error("Available assets:");
+  for (const name of [...available].sort()) console.error(`  - ${name}`);
+  exit(1);
+}
+
+console.log(
+  `RedDB ${release.tag_name} has required assets: ${required.join(", ")}`
+);