diff --git a/electron-builder.yml b/electron-builder.yml
index d8f3b67..4abacd6 100644
--- a/electron-builder.yml
+++ b/electron-builder.yml
@@ -21,6 +21,11 @@ linux:
   target:
     - AppImage
     - deb
+    # tar.gz is what the in-app updater installs (pickAsset looks for a
+    # linux x86_64/amd64 tarball); arch must be x64 so the asset name ends
+    # in -linux-x86_64 like every published release.
+    - target: tar.gz
+      arch: x64
 
 # OS file associations: double-click / "Open with Folio" on Markdown and
 # plain-text files imports them as books (see folio:openPathOrImport and
diff --git a/package-lock.json b/package-lock.json
index 6feb28d..6b4b766 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "folio",
-  "version": "0.1.10",
+  "version": "0.1.17",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "folio",
-      "version": "0.1.10",
+      "version": "0.1.17",
       "license": "MIT",
       "dependencies": {
         "@tiptap/core": "^2.27.2",
diff --git a/package.json b/package.json
index c5472ce..3ffd369 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "folio",
-  "version": "0.1.12",
+  "version": "0.1.17",
   "description": "A simple, local, open-source desktop writing app.",
   "productName": "Folio",
   "author": "Folio Contributors",
@@ -15,6 +15,7 @@
     "dev": "concurrently -k \"npm run build:watch\" \"wait-on dist/main.js && npm run electron\"",
     "start": "npm run build && npm run electron",
     "lint": "tsc --noEmit",
+    "prepackage": "npm run build",
     "test": "node tests/run-project-test.mjs && node tests/run-chapters-test.mjs && node tests/run-wikilinks-test.mjs && node tests/run-office-export-test.mjs && node tests/run-migration-test.mjs && node tests/run-editor-test.mjs && node tests/run-fullbook-test.mjs && node tests/run-print-test.mjs && node tests/run-update-import-test.mjs && node tests/run-update-installer-test.mjs && node tests/run-snapshots-test.mjs && node tests/run-search-test.mjs",
     "package": "electron-builder"
   },
diff --git a/src/main/index.ts b/src/main/index.ts
index e666950..c9557a1 100644
--- a/src/main/index.ts
+++ b/src/main/index.ts
@@ -1354,6 +1354,11 @@ handleIpc("folio:performUpdate", async () => {
       execFileSync("systemd-run", [
         "--user", "--quiet", "--collect",
         `--description=Folio updater handoff`,
+        // Default KillMode=control-group means the unit's cgroup is swept
+        // when the script exits — that killed the backgrounded relaunch
+        // before Electron got to start (v0.1.15 update: swap OK, app died).
+        // KillMode=process lets the script exit while its child app lives.
+        "--property=KillMode=process",
         "/bin/sh", script,
       ], { timeout: 10_000, stdio: "ignore" });
       handedOff = true;
@@ -1423,4 +1428,8 @@ if (app.requestSingleInstanceLock()) {
     }
     if (f) openFromArg(f);
   });
+} else {
+  // Lost the lock: another Folio is already running. Without this quit the
+  // second process falls through to whenReady() and opens a duplicate window.
+  app.quit();
 }
diff --git a/src/main/update.ts b/src/main/update.ts
index 738245b..9493643 100644
--- a/src/main/update.ts
+++ b/src/main/update.ts
@@ -224,7 +224,14 @@ export function buildInstallerScript(spec: InstallerSpec): string {
     '  rm -rf "$NEW"',
     "fi",
     'say "relaunching"',
-    '"$RELAUNCH" >/dev/null 2>&1 &',
+    // Detach fully: setsid moves the relaunch into its own session so it
+    // survives this script's exit and any cgroup sweep of the transient
+    // unit (systemd KillMode). Fallback chain for missing setsid.
+    'if command -v setsid >/dev/null 2>&1; then',
+    '  setsid "$RELAUNCH" >/dev/null 2>&1 < /dev/null &',
+    'else',
+    '  nohup "$RELAUNCH" >/dev/null 2>&1 < /dev/null &',
+    "fi",
     "",
   ].join("\n");
 }