diff --git a/apps/server/src/vcs/GitVcsDriverCore.test.ts b/apps/server/src/vcs/GitVcsDriverCore.test.ts
index 82d070f87cd0d8b7aa12d42bcb785892acbd6b66..c6e24caa62505c4c06bc01b03103727fbedbdef2 100644
--- a/apps/server/src/vcs/GitVcsDriverCore.test.ts
+++ b/apps/server/src/vcs/GitVcsDriverCore.test.ts
@@ -2159,6 +2159,28 @@ it.layer(layerTest)("GitVcsDriver core integration", (it) => {
       }),
     );
 
+    it.effect("skips Changes totals instead of indexing thousands of untracked files", () =>
+      Effect.gen(function* () {
+        const cwd = yield* makeTmpDir();
+        yield* initRepoWithCommit(cwd);
+        const driver = yield* GitVcsDriver.GitVcsDriver;
+        yield* Effect.forEach(
+          Array.from({ length: 5_001 }, (_, index) => `bulk/${index}.txt`),
+          (file) => writeTextFile(cwd, file, "x\n"),
+          { concurrency: 32, discard: true },
+        );
+        yield* writeTextFile(cwd, "README.md", "changed\n");
+
+        const status = yield* driver.statusDetailsLocal(cwd, { includeBranchChanges: true });
+        assert.isTrue(status.hasWorkingTreeChanges);
+        assert.isUndefined(status.branchChanges);
+
+        const preview = yield* driver.getReviewDiffPreview({ cwd });
+        assert.isNotEmpty(preview.sources);
+        assert.isTrue(preview.sources.every((source) => source.truncated));
+      }),
+    );
+
     it.effect("Changes does not show newer base commits as deletions", () =>
       Effect.gen(function* () {
         const cwd = yield* makeTmpDir();
diff --git a/apps/server/src/vcs/GitVcsDriverCore.ts b/apps/server/src/vcs/GitVcsDriverCore.ts
index d07baa1727c15ca68dae08c9d90d7a5bf816ca7d..140786cce0a469a2bddbda6b50759e4110a6f3ef 100644
--- a/apps/server/src/vcs/GitVcsDriverCore.ts
+++ b/apps/server/src/vcs/GitVcsDriverCore.ts
@@ -59,6 +59,10 @@ const RANGE_DIFF_SUMMARY_MAX_OUTPUT_BYTES = 19_000;
 const RANGE_DIFF_PATCH_MAX_OUTPUT_BYTES = 59_000;
 const REVIEW_DIFF_PATCH_MAX_OUTPUT_BYTES = 120_000;
 const REVIEW_METADATA_MAX_OUTPUT_BYTES = 16 * 1024 * 1024;
+// Every status refresh adds the untracked files to a temporary index, and git add's cost grows
+// much faster than the file count (50k files took about 30 seconds). Past this many, the
+// totals are reported incomplete instead.
+const REVIEW_UNTRACKED_MAX_FILES = 5_000;
 const REVIEW_DIFF_FILE_MAX_OUTPUT_BYTES = 1024 * 1024;
 // Patches the clients render are parsed against git's default a/ and b/ path
 // prefixes. A repository or global diff.noprefix or diff.mnemonicPrefix would
@@ -2618,7 +2622,7 @@ export const makeGitVcsDriverCore = Effect.fn("makeGitVcsDriverCore")(function*
   });
 
   // Lists untracked files and adds them to a temporary index, so a diff against any commit
-  // shows them as new. Returns null when the list is too big to read. Needs a Scope.
+  // shows them as new. Returns null when the list is too big to read or to index. Needs a Scope.
   const prepareUntrackedReviewIndex = Effect.fn("prepareUntrackedReviewIndex")(function* (
     cwd: string,
     pathArgs: ReadonlyArray<string>,
@@ -2640,6 +2644,7 @@ export const makeGitVcsDriverCore = Effect.fn("makeGitVcsDriverCore")(function*
       (candidate) => onlyPath === undefined || candidate === onlyPath,
     );
     if (paths.length === 0) return { env: undefined };
+    if (paths.length > REVIEW_UNTRACKED_MAX_FILES) return null;
     const env = yield* prepareReviewIndex(cwd, paths).pipe(
       Effect.catchTags({
         PlatformError: (cause) =>