diff --git a/apps/electron-backend/tsconfig.json b/apps/electron-backend/tsconfig.json
index 522574b2b..0d3637e7d 100644
--- a/apps/electron-backend/tsconfig.json
+++ b/apps/electron-backend/tsconfig.json
@@ -4,7 +4,9 @@
         "types": ["node"],
         "moduleResolution": "nodenext",
         "module": "NodeNext",
-        "ignoreDeprecations": "6.0"
+        "ignoreDeprecations": "6.0",
+        "target": "ES2022",
+        "useDefineForClassFields": false
     },
     "include": ["**/*.ts"]
 }
diff --git a/docs/development/electron-debugging.md b/docs/development/electron-debugging.md
index f4c594095..4ee34e510 100644
--- a/docs/development/electron-debugging.md
+++ b/docs/development/electron-debugging.md
@@ -134,3 +134,17 @@ from `app.asar`. The preload is
 [workspace shell](../architecture/workspace-shell.md) for window behavior,
 [DB worker](../architecture/sqlite-db-worker.md) for worker ownership and
 [Electron security](../architecture/electron-security.md) for bridge boundaries.
+
+`apps/electron-backend/tsconfig.json` sets `"target": "ES2022"` for the
+main-process bundles (`main.js`, `main.app.js`, `deferred-events.js`), the
+preloads and the backend's Jest specs; `tsconfig.base.json` stays at `es2015`
+because other projects inherit it. Electron 43 (Node 24 and Chromium's V8) runs
+ES2022 natively in the main process and in the sandboxed preload, so
+async/await, optional chaining and `??` are no longer downleveled.
+`"useDefineForClassFields": false` keeps the class-field semantics of the old
+target (constructor assignment, not `[[Define]]`), so only syntax changed. The
+workers built by `build-worker.js` (esbuild, `node18`) were already native. On
+2026-09-29 the four bundles shrank from 2,008,115 to 1,853,599 bytes (every
+inlined `__awaiter` gone); neither main-process CPU time to `did-finish-load`
+nor the J1 launch journey's wall-clock changed measurably in an interleaved
+A/B, and J1's counters were identical.