chore(ts): enable noUncheckedIndexedAccess + fix all 323 errors

apps/loadout-overlay/src/bun/native/deck-hidraw-watcher.ts

@@ -131,7 +131,9 @@ export async function startDeckHidrawWatcher(
       // button map per frame is unnecessary on the hot path — chase the one
       // bit and bail. (Less GC pressure than building a Map every report.)
       if (bound) {
-        const cur = (report[bound.byte] & (1 << bound.bit)) !== 0;
+        // splitReports only yields full REPORT_LEN (64-byte) frames and
+        // bound.byte is always < 64, so this index is provably in-bounds.
+        const cur = (report[bound.byte]! & (1 << bound.bit)) !== 0;
         if (cur && !lastBitValue && !suppressNextEdge) {
           opts.onWake("QamToggle");
         }

apps/loadout-overlay/src/bun/native/devices.ts

@@ -164,7 +164,8 @@ export function hasCapability(caps: Uint8Array, code: number): boolean {
   const byteIdx = code >> 3;
   const bitIdx = code & 0x07;
   if (byteIdx >= caps.length) return false;
-  return (caps[byteIdx] & (1 << bitIdx)) !== 0;
+  // Guarded above: byteIdx < caps.length, so this index is in-bounds.
+  return (caps[byteIdx]! & (1 << bitIdx)) !== 0;
 }
 
 /**

apps/loadout-overlay/src/bun/native/gamescope-atoms.ts

@@ -286,7 +286,7 @@ export class GamescopeAtoms {
         for (const line of lines) {
           if (!line.startsWith(prefix + "(")) continue;
           const m = line.match(/=\s*"((?:[^"\\]|\\.)*)"/);
-          if (m) return m[1];
+          if (m) return m[1] ?? null;
         }
       }
       return null;
@@ -311,6 +311,9 @@ export class GamescopeAtoms {
         managed.push(id);
       }
     }
+    // The sole caller only invokes this with a non-empty candidate set
+    // (findSteamWindow returns early when allIds is empty), so pool is
+    // guaranteed non-empty and pool[0] below is always defined.
     const pool = managed.length > 0 ? managed : candidates;
 
     // Prefer a pool window currently claiming overlay/focus.
@@ -326,7 +329,7 @@ export class GamescopeAtoms {
         return id;
       }
     }
-    return pool[0];
+    return pool[0]!;
   }
 
   /** True if `atom` is set on `windowId`. Uses xprop output to
@@ -851,7 +854,9 @@ export class GamescopeAtoms {
         const m = line.match(/^(\w+)\([^)]+\)\s*=\s*(-?\d+)/);
         if (!m) continue;
         const n = Number(m[2]);
-        if (Number.isFinite(n)) out.set(m[1], n);
+        // Both capture groups are mandatory in the regex, so on a match
+        // m[1] is always present.
+        if (Number.isFinite(n)) out.set(m[1]!, n);
       }
     } catch (err) {
       console.warn(

apps/loadout-overlay/src/bun/native/input-intercept.ts

@@ -211,7 +211,9 @@ function buildBitmask(codes: readonly number[]): Uint8Array {
   if (byteLen < 8) byteLen = 8;
   const bits = new Uint8Array(byteLen);
   for (const code of codes) {
-    bits[code >> 3] |= 1 << (code & 7);
+    // byteLen covers (maxCode >> 3) + 1 bytes and code <= maxCode, so
+    // code >> 3 is always in-bounds.
+    bits[code >> 3]! |= 1 << (code & 7);
   }
   return bits;
 }
@@ -411,7 +413,9 @@ function readModifierState(fd: number): { guide: boolean; select: boolean } {
   const buf = new Uint8Array(96);
   const rc = libc.symbols.ioctl(fd, eviocgkey(buf.length), ptr(buf));
   if (rc < 0) return { guide: false, select: false };
-  const bit = (code: number) => (buf[code >> 3] & (1 << (code & 7))) !== 0;
+  // The 96-byte buffer covers codes 0..767, past every code we query, so
+  // code >> 3 is always in-bounds.
+  const bit = (code: number) => (buf[code >> 3]! & (1 << (code & 7))) !== 0;
   return { guide: bit(BTN_MODE), select: bit(BTN_SELECT) };
 }
 
@@ -979,6 +983,7 @@ export async function startInputIntercept(
     const idx = tracked.findIndex((t) => t.path === eventPath);
     if (idx < 0) return;
     const [t] = tracked.splice(idx, 1);
+    if (!t) return;
     // Drop any deferred-grab entry before closing the fd: a stale entry would
     // make pollOnce ioctl a closed (possibly OS-reused) fd next tick.
     pendingGrabs.delete(t);

apps/loadout-overlay/src/bun/native/ip-intercept.ts

@@ -203,9 +203,11 @@ export function parseInputEventLine(
 ): { cap: string; value: number } | null {
   const m = line.match(/\.InputEvent\s+\('([^']+)',\s*([-0-9.eE]+)\)/);
   if (!m) return null;
-  const value = Number.parseFloat(m[2]);
+  // Both capture groups are mandatory in the regex, so on a match m[1]
+  // and m[2] are always present.
+  const value = Number.parseFloat(m[2]!);
   if (Number.isNaN(value)) return null;
-  return { cap: m[1], value };
+  return { cap: m[1]!, value };
 }
 
 // ---- Public API ------------------------------------------------------------

apps/loadout-overlay/src/overlay/components/Settings.tsx

@@ -777,7 +777,7 @@ function SettingsInner({
                           : "bg-base-300/70 text-base-content/50"
                       }`}
                     >
-                      {(plugin.icon ?? plugin.name)[0].toUpperCase()}
+                      {(plugin.icon ?? plugin.name).charAt(0).toUpperCase()}
                     </div>
                     <div className="flex-1 min-w-0">
                       <div className="text-sm font-medium text-base-content truncate">

apps/loadout-overlay/src/overlay/components/Sidebar.tsx

@@ -83,7 +83,8 @@ export function Sidebar({
       }
       bucket[cat].push(p);
     }
-    const result = order.map((name) => ({ name, items: bucket[name] }));
+    // Every name in `order` was pushed alongside its bucket entry above.
+    const result = order.map((name) => ({ name, items: bucket[name] ?? [] }));
     if (favSet.size > 0) {
       const favPlugins = favorites
         .map((id) => plugins.find((p) => p.id === id))
@@ -263,7 +264,7 @@ export function Sidebar({
                                     aria-hidden
                                   />
                                 ) : (
-                                  <span>{(plugin.icon ?? plugin.name)[0].toUpperCase()}</span>
+                                  <span>{(plugin.icon ?? plugin.name).charAt(0).toUpperCase()}</span>
                                 )
                               }
                               label={plugin.name}

apps/loadout-overlay/src/overlay/components/WelcomeScreen.tsx

@@ -102,7 +102,8 @@ export function WelcomeScreen({
   const scrollRef = useRef<HTMLDivElement>(null);
 
   const [stepIndex, setStepIndex] = useState(0);
-  const stepId = STEPS[stepIndex].id;
+  // stepIndex is clamped to [0, STEPS.length) by the nav handlers.
+  const stepId = STEPS[stepIndex]!.id;
 
   // Theme — controlled locally during the flow so navigating around
   // applies the preview immediately, then we persist on completion.
@@ -423,7 +424,8 @@ function StepHeader({
       sub: "Press Open Loadout to head to your home dashboard. Everything below can be tweaked from the Settings page.",
     },
   };
-  const stepId = STEPS[stepIndex].id;
+  // stepIndex is clamped to [0, STEPS.length) by the nav handlers.
+  const stepId = STEPS[stepIndex]!.id;
   const h = headers[stepId];
   return (
     <div className="px-9 pt-8 pb-4">
@@ -1375,7 +1377,7 @@ function StepPlugins({
                     : "bg-base-300/70 text-base-content/50"
                 }`}
               >
-                {(plugin.icon ?? plugin.name)[0].toUpperCase()}
+                {(plugin.icon ?? plugin.name).charAt(0).toUpperCase()}
               </div>
               <div className="flex-1 min-w-0">
                 <div className="text-sm font-medium text-base-content truncate">

apps/loadout-overlay/src/overlay/components/WidgetPicker.tsx

@@ -153,7 +153,7 @@ export function WidgetPicker({
             {!probing &&
               availablePlugins.map((plugin) => {
                 const isAdded = favorites.includes(plugin.id);
-                const initial = (plugin.icon ?? plugin.name)[0].toUpperCase();
+                const initial = (plugin.icon ?? plugin.name).charAt(0).toUpperCase();
                 return (
                   <Focusable
                     key={plugin.id}

apps/loadout-overlay/src/overlay/hooks/useGamepadInput.ts

@@ -152,8 +152,9 @@ export function useGamepadInput(onBack?: () => void) {
 
         // Left stick → arrow keys
         if (gp.axes.length >= 2) {
-          const lx = gp.axes[0];
-          const ly = gp.axes[1];
+          // Guarded by length >= 2, so axes[0] and axes[1] are present.
+          const lx = gp.axes[0]!;
+          const ly = gp.axes[1]!;
           handlePress("stick-left", "ArrowLeft", lx < -STICK_DEADZONE, now);
           handlePress("stick-right", "ArrowRight", lx > STICK_DEADZONE, now);
           handlePress("stick-up", "ArrowUp", ly < -STICK_DEADZONE, now);
@@ -165,8 +166,9 @@ export function useGamepadInput(onBack?: () => void) {
         // pairs beyond the two sticks (axes 0-3).
         for (let ai = 4; ai < gp.axes.length; ai += 2) {
           if (ai + 1 >= gp.axes.length) break;
-          const dx = gp.axes[ai];
-          const dy = gp.axes[ai + 1];
+          // Guarded above: ai and ai + 1 are both < axes.length.
+          const dx = gp.axes[ai]!;
+          const dy = gp.axes[ai + 1]!;
           handlePress(`daxis${ai}-left`, "ArrowLeft", dx < -STICK_DEADZONE, now);
           handlePress(`daxis${ai}-right`, "ArrowRight", dx > STICK_DEADZONE, now);
           handlePress(`daxis${ai}-up`, "ArrowUp", dy < -STICK_DEADZONE, now);
@@ -175,7 +177,8 @@ export function useGamepadInput(onBack?: () => void) {
 
         // Right stick → smooth analog scroll with momentum
         if (gp.axes.length >= 4) {
-          const ry = gp.axes[3];
+          // Guarded by length >= 4, so axes[3] is present.
+          const ry = gp.axes[3]!;
           if (Math.abs(ry) > RIGHT_STICK_DEADZONE) {
             scrollVelocity = ry * RIGHT_STICK_SPEED;
           } else {

apps/loadout/src/injector/injector.ts

@@ -642,7 +642,7 @@ export class SteamInjector {
             menuPlugins.push({
               pluginId: plugin.id,
               title: t.title ?? plugin.name,
-              route: t.route ?? (plugin.routes ? Object.keys(plugin.routes)[0] : ""),
+              route: t.route ?? (plugin.routes ? (Object.keys(plugin.routes)[0] ?? "") : ""),
               position: typeof t.position === "number" ? t.position : undefined,
               icon: t.icon,
             });

apps/loadout/src/injector/tabs.ts

@@ -135,5 +135,6 @@ export async function findQuickAccessTab(options: GetTabsOptions): Promise<CEFTa
   }
 
   // Return the first one — typically the Big Picture Mode QAM
-  return qaTabs[0];
+  // Non-null: qaTabs.length was checked > 0 above.
+  return qaTabs[0]!;
 }

apps/loadout/src/loader/auth.ts

@@ -34,7 +34,7 @@ function extractToken(req: Request): string | null {
   if (authHeader) {
     const match = authHeader.match(/^Bearer\s+(.+)$/i);
     if (match) {
-      return match[1];
+      return match[1] ?? null;
     }
   }
 

apps/loadout/src/loader/index.ts

@@ -175,7 +175,8 @@ async function compileTsx(
     });
 
     if (result.success && result.outputs.length > 0) {
-      const code = await result.outputs[0].text();
+      // Non-null: outputs.length was checked > 0 above.
+      const code = await result.outputs[0]!.text();
       return { code, ok: true };
     }
 

apps/loadout/src/loader/inject-builder.ts

@@ -129,7 +129,8 @@ import * as ReactDOMClient from "react-dom/client";
         target: "browser",
       });
       if (vendorResult.success && vendorResult.outputs.length > 0) {
-        vendorBundle = await Bun.file(vendorResult.outputs[0].path).text();
+        // Non-null: outputs.length was checked > 0 above.
+        vendorBundle = await Bun.file(vendorResult.outputs[0]!.path).text();
       } else {
         console.error("Failed to build vendor bundle:", vendorResult.logs);
       }
@@ -169,7 +170,8 @@ import * as ReactDOMClient from "react-dom/client";
     });
 
     if (sdkResult.success && sdkResult.outputs.length > 0) {
-      const sdkCode = await Bun.file(sdkResult.outputs[0].path).text();
+      // Non-null: outputs.length was checked > 0 above.
+      const sdkCode = await Bun.file(sdkResult.outputs[0]!.path).text();
       sdkBundle = transformToIIFE(sdkCode, "__LOADOUT_SDK");
     } else {
       console.error("Failed to build inject SDK:", sdkResult.logs);
@@ -205,17 +207,20 @@ function transformToIIFE(esmCode: string, globalName: string): string {
     coreCode = esmCode.slice(0, exportMatch.index).trimEnd();
 
     // Parse export names (handle `name as alias` syntax)
-    const names = exportMatch[1].split(",").map((s) => s.trim());
+    // Non-null: exportMatch is truthy, group 1 is a required capture.
+    const names = exportMatch[1]!.split(",").map((s) => s.trim());
     for (const name of names) {
       const parts = name.split(/\s+as\s+/);
-      // Use the original name (before "as"), which is the local variable
-      exportNames.push(parts[0].trim());
+      // Use the original name (before "as"), which is the local variable.
+      // Non-null: split always yields at least one element.
+      exportNames.push(parts[0]!.trim());
     }
   }
 
   if (defaultExportMatch && !exportMatch) {
     coreCode = esmCode.slice(0, defaultExportMatch.index).trimEnd();
-    exportNames.push(defaultExportMatch[1]);
+    // Non-null: defaultExportMatch is truthy, group 1 is a required capture.
+    exportNames.push(defaultExportMatch[1]!);
   }
 
   // Build the assignments

apps/loadout/src/loader/routes/plugins.ts

@@ -50,7 +50,8 @@ export const pluginAppBundleRoute: RouteHandler = {
   match: (_req, url) => APP_BUNDLE_PATTERN.test(url.pathname),
   async handle(_req, url, ctx) {
     const match = url.pathname.match(APP_BUNDLE_PATTERN)!;
-    const pluginId = match[1];
+    // Non-null: group 1 is a required capture in APP_BUNDLE_PATTERN.
+    const pluginId = match[1]!;
     let code = ctx.bundleCache.get(pluginId);
     if (!code) {
       const appPath = join(ctx.pluginsDir, pluginId, "app.tsx");
@@ -66,8 +67,9 @@ export const pluginAssetRoute: RouteHandler = {
   match: (_req, url) => ASSET_PATTERN.test(url.pathname),
   async handle(_req, url, ctx) {
     const match = url.pathname.match(ASSET_PATTERN)!;
-    const pluginId = match[1];
-    const relPath = decodeURIComponent(match[2]);
+    // Non-null: groups 1 and 2 are required captures in ASSET_PATTERN.
+    const pluginId = match[1]!;
+    const relPath = decodeURIComponent(match[2]!);
     if (!ctx.plugins.has(pluginId)) {
       return new Response("Not Found", { status: 404 });
     }

apps/loadout/src/loader/routes/steam-grid.ts

@@ -200,6 +200,13 @@ export const steamGridRoute: RouteHandler = {
     const perUser = url.pathname.match(STEAM_GRID_PATTERN);
     if (perUser) {
       const [, idPart, userIdPart, type] = perUser;
+      if (
+        idPart === undefined ||
+        userIdPart === undefined ||
+        type === undefined
+      ) {
+        return new Response("not found", { status: 404 });
+      }
       const t = type as SteamGridType;
       const candidates = steamGridCandidates(idPart, t);
       const gridDir = join(
@@ -238,6 +245,9 @@ export const steamGridRoute: RouteHandler = {
     const auto = url.pathname.match(STEAM_GRID_AUTO_PATTERN);
     if (!auto) return new Response("not found", { status: 404 });
     const [, idPart, type] = auto;
+    if (idPart === undefined || type === undefined) {
+      return new Response("not found", { status: 404 });
+    }
     const t = type as SteamGridType;
     const candidates = steamGridCandidates(idPart, t);
     const userdata = getUserdataDir();

apps/loadout/src/loader/services/game-detection.ts

@@ -44,7 +44,8 @@ export class GameDetectionService implements PluginBackend {
     const endTime = Date.now();
     const idx = this.recent.findIndex((s) => s.appId === appId && s.endTime === undefined);
     if (idx >= 0) {
-      this.recent[idx] = { ...this.recent[idx], endTime };
+      // Non-null: idx comes from findIndex and is >= 0, so it is in bounds.
+      this.recent[idx] = { ...this.recent[idx]!, endTime };
     }
     if (this.current && this.current.appId === appId) {
       this.current = null;

apps/loadout/src/loader/target-user.ts

@@ -46,7 +46,8 @@ export function resolveUser(
       const uid = Number(f[2]);
       const gid = Number(f[3]);
       if (Number.isFinite(uid) && Number.isFinite(gid)) {
-        return { uid, gid, home: f[5] };
+        // Non-null: f.length was checked >= 6 above.
+        return { uid, gid, home: f[5]! };
       }
     }
   }

packages/deck-hid/src/index.ts

@@ -128,15 +128,17 @@ export function parseHidUEvent(content: string): HidUEvent {
       // Format: BUS:VENDOR:PRODUCT, all hex, vendor/product zero-padded to 8.
       const parts = value.split(":");
       if (parts.length === 3) {
-        out.bus = parseInt(parts[0], 16);
-        out.vendor = parseInt(parts[1], 16);
-        out.product = parseInt(parts[2], 16);
+        // Non-null: parts.length was checked === 3 above.
+        out.bus = parseInt(parts[0]!, 16);
+        out.vendor = parseInt(parts[1]!, 16);
+        out.product = parseInt(parts[2]!, 16);
       }
     } else if (key === "HID_PHYS") {
       out.hidPhys = value;
       // Tail "/inputN" — the kernel encodes the USB interface number here.
       const m = value.match(/\/input(\d+)\s*$/);
-      if (m) out.interfaceNum = parseInt(m[1], 10);
+      // Non-null: m is truthy, group 1 is a required capture.
+      if (m) out.interfaceNum = parseInt(m[1]!, 10);
     }
   }
   return out;
@@ -199,7 +201,7 @@ export function decodeButtons(report: Buffer): Map<string, boolean> | null {
   if (report[0] !== REPORT_ID_INPUT) return null;
   const out = new Map<string, boolean>();
   for (const [byteIdx, defs] of DECK_BUTTONS_BY_BYTE) {
-    const v = report[byteIdx];
+    const v = report[byteIdx] ?? 0;
     for (const { bit, name } of defs) {
       out.set(name, (v & (1 << bit)) !== 0);
     }

packages/game-library/src/index.ts

@@ -153,7 +153,7 @@ async function readUserCollections(
   const match = text.match(/"user-collections"\s*"((?:[^"\\]|\\.)*)"/);
   if (!match) return new Map();
 
-  const escaped = match[1];
+  const escaped = match[1] ?? "";
   const unescaped = escaped.replace(/\\\\/g, "\\").replace(/\\"/g, '"');
 
   let collections: Record<string, { id?: string; added?: number[] }>;
@@ -190,7 +190,7 @@ async function readUserCollections(
 function parseVdfValue(content: string, key: string): string | null {
   const regex = new RegExp(`"${key}"\\s+"([^"]*)"`, "i");
   const match = content.match(regex);
-  return match ? match[1] : null;
+  return match ? (match[1] ?? null) : null;
 }
 
 /**