diff --git a/packages/compiler/test/forin-keys.test.ts b/packages/compiler/test/forin-keys.test.ts
index b35ff2154..4a8d24c7e 100644
--- a/packages/compiler/test/forin-keys.test.ts
+++ b/packages/compiler/test/forin-keys.test.ts
@@ -36,7 +36,7 @@ console.log(count(row), count(JSON.parse('{"b":1}')));
   expect(llvm).not.toContain("@scr_dyn_for_in_keys(");
   // Fully required record shapes are marked fixed for the stable walk.
   expect(llvm).toMatch(
-    /_rops = internal global \{ i64, ptr, ptr, ptr, i8, ptr, ptr \} \{[^}]*i8 1, ptr null, ptr null \}/,
+    /_rops = internal global \{ i64, ptr, ptr, ptr, i8, ptr, ptr, ptr \} \{[^}]*i8 1, ptr null, ptr null, ptr null \}/,
   );
 });
 
diff --git a/scripts/zero-cost-compare.mjs b/scripts/zero-cost-compare.mjs
index df407bbb7..b412fa72a 100644
--- a/scripts/zero-cost-compare.mjs
+++ b/scripts/zero-cost-compare.mjs
@@ -401,7 +401,9 @@ export function dynamicTierSymbols(names) {
  * bench/dynamic-properties are untyped JavaScript. bench/regex-replacers,
  * also added later, passes checked-dynamic values to replace callbacks
  * whose parameters the lib types `any`: captures a match can leave unset
- * and results the checker types `any`. Every other bench workload is fully typed and must link none. The gate and
+ * and results the checker types `any`. bench/record-untyped-writes, also
+ * added later, writes typed records through `unknown` and `Object.assign`
+ * views. Every other bench workload is fully typed and must link none. The gate and
  * tests/harness/bench-dynamic-tier.test.ts enforce that, and the test also
  * fails when a listed workload stops linking them, so remove a workload here
  * when a leak fix makes its binary clean. */
@@ -425,6 +427,7 @@ export const DYNAMIC_WORKLOADS = new Set([
   "bench/json-unions",
   "bench/throw-chains",
   "bench/regex-replacers",
+  "bench/record-untyped-writes",
 ]);
 
 /** Names of the functions (text and weak symbols) in `nm` output. Mach-O
diff --git a/tests/harness/self-hosting-emission.test.ts b/tests/harness/self-hosting-emission.test.ts
index 3977ede29..6d27b7851 100644
--- a/tests/harness/self-hosting-emission.test.ts
+++ b/tests/harness/self-hosting-emission.test.ts
@@ -59,6 +59,8 @@ test("the production layout and metadata stage lowers statically", async () => {
 });
 
 for (const backend of ["llvm"] as const) {
+  // A sanitized build of the fixture and its emission cases take about half
+  // the default 300 s budget on an idle 16-core host.
   test(`native LLVM layout and metadata emission (${backend})`, async () => {
     const dir = mkdtempSync(
       join(process.platform === "win32" ? tmpdir() : "/tmp", "scriptc-native-emission-"),
@@ -268,5 +270,5 @@ for (const backend of ["llvm"] as const) {
     } finally {
       rmSync(dir, { recursive: true, force: true });
     }
-  });
+  }, 600_000);
 }