diff --git a/mobile/src/transport/mobile-web-bundle-fetch-range.test.ts b/mobile/src/transport/mobile-web-bundle-fetch-range.test.ts
index bd2bf362b20..0d58d2fad52 100644
--- a/mobile/src/transport/mobile-web-bundle-fetch-range.test.ts
+++ b/mobile/src/transport/mobile-web-bundle-fetch-range.test.ts
@@ -12,12 +12,11 @@ import type { RpcClient } from './rpc-client'
 import type { RpcResponse } from './types'
 
 type Inflation = { readonly outLength: number; readonly resultLength: number }
+type LoggedInflation = Inflation & { readonly body: Uint8Array }
 
 /** Every inflation in the process, keyed by the gzip body it was handed; a host reads back only
  *  the bodies it sent, so a read left running by an earlier test's fetch never lands in its sink. */
-const inflationLog = vi.hoisted(
-  () => [] as { body: Uint8Array; outLength: number; resultLength: number }[]
-)
+const inflationLog = vi.hoisted((): LoggedInflation[] => [])
 
 // Observes the bound the decoder hands fflate, and what fflate hands back inside it.
 vi.mock('fflate', async (importOriginal) => {
diff --git a/mobile/src/transport/mobile-web-bundle-reply-schemas.ts b/mobile/src/transport/mobile-web-bundle-reply-schemas.ts
index e8bcb3c3230..ea68e7dbd14 100644
--- a/mobile/src/transport/mobile-web-bundle-reply-schemas.ts
+++ b/mobile/src/transport/mobile-web-bundle-reply-schemas.ts
@@ -130,7 +130,7 @@ export const MobileWebBundleManifestReplySchema = z.looseObject({
 /** Self-describing on purpose: `buildId`, `path` and `offset` are echoed so a reassembler cannot
  *  misplace a reply, and `sha256`/`assetByteLength` describe the whole asset rather than this
  *  window, which is what lets the fetch verify without a second index. Shared by both read replies. */
-const windowHeaderShape = {
+const windowHeaderFields = {
   buildId: z.string().regex(SHA256_PATTERN),
   path: MobileWebBundleAssetPathSchema,
   offset: z.number().int().nonnegative().max(MOBILE_WEB_BUNDLE_MAX_ASSET_BYTES),
@@ -140,7 +140,7 @@ const windowHeaderShape = {
 }
 
 export const MobileWebBundleChunkReplySchema = z.looseObject({
-  ...windowHeaderShape,
+  ...windowHeaderFields,
   dataBase64: z.string().max(MAX_DATA_BASE64_LENGTH)
 })
 
@@ -148,7 +148,7 @@ export const MobileWebBundleChunkReplySchema = z.looseObject({
  *  enum: an encoding this build cannot decode is a typed refusal at the decoder, which names it,
  *  rather than a reply-shape failure that names nothing. */
 export const MobileWebBundleRangeReplySchema = z.looseObject({
-  ...windowHeaderShape,
+  ...windowHeaderFields,
   encoding: z.string().min(1).max(32),
   dataBase64: z.string().max(MOBILE_WEB_BUNDLE_RANGE_MAX_DATA_BASE64_LENGTH)
 })
diff --git a/src/shared/mobile-web-bundle/bundle-rpc-contract.ts b/src/shared/mobile-web-bundle/bundle-rpc-contract.ts
index d740e78fee9..9541985b5a8 100644
--- a/src/shared/mobile-web-bundle/bundle-rpc-contract.ts
+++ b/src/shared/mobile-web-bundle/bundle-rpc-contract.ts
@@ -64,7 +64,7 @@ export const MobileWebBundleManifestResultSchema = z
   })
   .strict()
 
-const windowParamsShape = {
+const windowParamsFields = {
   buildId: z.string().regex(SHA256_PATTERN),
   path: MobileWebBundleAssetPathSchema,
   offset: z.number().int().nonnegative().max(MOBILE_WEB_BUNDLE_MAX_ASSET_BYTES)
@@ -72,14 +72,14 @@ const windowParamsShape = {
 
 /** No `multipleOf` pin on `offset`: alignment is against the host's advertised `chunkBytes`, which
  *  may be smaller than the constant, so the host rejects a misaligned offset instead. */
-export const MobileWebBundleChunkParamsSchema = z.object(windowParamsShape).strict()
+export const MobileWebBundleChunkParamsSchema = z.object(windowParamsFields).strict()
 
 /** The chunk params exactly, on the `rangeBytes` grid the manifest reply advertised. */
 export const MobileWebBundleRangeParamsSchema = MobileWebBundleChunkParamsSchema
 
 /** What every chunk or range reply restates about the window it answers. */
-const windowHeaderShape = {
-  ...windowParamsShape,
+const windowHeaderFields = {
+  ...windowParamsFields,
   /** The whole asset, not this window: named for it so a reassembler cannot misread the two, and
    *  paired with `sha256` it describes the asset without a second index. */
   assetByteLength: z.number().int().nonnegative().max(MOBILE_WEB_BUNDLE_MAX_ASSET_BYTES),
@@ -90,14 +90,14 @@ const windowHeaderShape = {
 /** Strict, so a later `contentEncoding` is only a Rule 1 optional-field addition for clients whose
  *  own reply readers are not strict. */
 export const MobileWebBundleChunkResultSchema = z
-  .object({ ...windowHeaderShape, dataBase64: z.string().max(MAX_DATA_BASE64_LENGTH) })
+  .object({ ...windowHeaderFields, dataBase64: z.string().max(MAX_DATA_BASE64_LENGTH) })
   .strict()
 
 /** A chunk result plus the encoding of `dataBase64`, whose decoded length is
  *  `min(rangeBytes, assetByteLength - offset)`. */
 export const MobileWebBundleRangeResultSchema = z
   .object({
-    ...windowHeaderShape,
+    ...windowHeaderFields,
     encoding: z.enum(MOBILE_WEB_BUNDLE_RANGE_ENCODINGS),
     dataBase64: z.string().max(MOBILE_WEB_BUNDLE_RANGE_MAX_DATA_BASE64_LENGTH)
   })