diff --git a/web/packages/base/crypto/index.ts b/web/packages/base/crypto/index.ts
index 98f577eaa7..a43c7673d7 100644
--- a/web/packages/base/crypto/index.ts
+++ b/web/packages/base/crypto/index.ts
@@ -111,7 +111,7 @@ let _comlinkWorker: ComlinkWorker<typeof CryptoWorker> | undefined;
 /**
  * Lazily created, cached, instance of a CryptoWorker web worker.
  */
-export const sharedCryptoWorker = async () =>
+export const sharedCryptoWorker = () =>
     (_comlinkWorker ??= createComlinkCryptoWorker()).remote;
 
 /** A shorter alias of {@link sharedCryptoWorker} for use within this file. */
@@ -144,7 +144,7 @@ export const toB64URLSafe = (bytes: Uint8Array): Promise<string> =>
 /**
  * Convert a base64 string to bytes ({@link Uint8Array}).
  */
-export const fromB64 = (b64String: string) =>
+export const fromB64 = (b64String: string): Promise<Uint8Array> =>
     inWorker()
         ? ei._fromB64(b64String)
         : sharedWorker().then((w) => w.fromB64(b64String));
@@ -160,7 +160,7 @@ export const toHex = (b64String: string): Promise<string> =>
 /**
  * Convert a hex string to the base64 representation of the underlying bytes.
  */
-export const fromHex = (hexString: string) =>
+export const fromHex = (hexString: string): Promise<string> =>
     inWorker()
         ? ei._fromHex(hexString)
         : sharedWorker().then((w) => w.fromHex(hexString));
@@ -286,7 +286,7 @@ export const encryptMetadataJSON = (
  * Encrypt the given data using chunked streaming encryption, but process all
  * the chunks in one go.
  */
-export const encryptStreamBytes = async (
+export const encryptStreamBytes = (
     data: Uint8Array,
     key: BytesOrB64,
 ): Promise<EncryptedFile> =>
@@ -305,11 +305,11 @@ export const initChunkEncryption = async (key: BytesOrB64) =>
 /**
  * Encrypt a chunk as part of a chunked streaming encryption.
  */
-export const encryptStreamChunk = async (
+export const encryptStreamChunk = (
     data: Uint8Array,
     state: StateAddress,
     isFinalChunk: boolean,
-) =>
+): Promise<Uint8Array> =>
     inWorker()
         ? ei._encryptStreamChunk(data, state, isFinalChunk)
         : sharedWorker().then((w) =>
@@ -332,7 +332,10 @@ export const decryptBox = (
  * Variant of {@link decryptBox} that returns the decrypted bytes as it is
  * (without encoding them to base64).
  */
-export const decryptBoxBytes = (box: EncryptedBox, key: BytesOrB64) =>
+export const decryptBoxBytes = (
+    box: EncryptedBox,
+    key: BytesOrB64,
+): Promise<Uint8Array> =>
     inWorker()
         ? ei._decryptBoxBytes(box, key)
         : sharedWorker().then((w) => w.decryptBoxBytes(box, key));
@@ -366,7 +369,10 @@ export const decryptBlob = (
  * A variant of {@link decryptBlobBytes} that returns the result bytes directly
  * (instead of encoding them as a base64 string).
  */
-export const decryptBlobBytes = (blob: EncryptedBlob, key: BytesOrB64) =>
+export const decryptBlobBytes = (
+    blob: EncryptedBlob,
+    key: BytesOrB64,
+): Promise<Uint8Array> =>
     inWorker()
         ? ei._decryptBlobBytes(blob, key)
         : sharedWorker().then((w) => w.decryptBlobBytes(blob, key));
@@ -374,10 +380,10 @@ export const decryptBlobBytes = (blob: EncryptedBlob, key: BytesOrB64) =>
 /**
  * Decrypt the result of {@link encryptStreamBytes}.
  */
-export const decryptStreamBytes = async (
+export const decryptStreamBytes = (
     file: EncryptedFile,
     key: BytesOrB64,
-) =>
+): Promise<Uint8Array> =>
     inWorker()
         ? ei._decryptStreamBytes(file, key)
         : sharedWorker().then((w) => w.decryptStreamBytes(file, key));
@@ -396,10 +402,10 @@ export const initChunkDecryption = async (header: string, key: BytesOrB64) =>
  *
  * This function is used in tandem with {@link initChunkDecryption}.
  */
-export const decryptStreamChunk = async (
+export const decryptStreamChunk = (
     data: Uint8Array,
     state: StateAddress,
-) =>
+): Promise<Uint8Array> =>
     inWorker()
         ? ei._decryptStreamChunk(data, state)
         : sharedWorker().then((w) => w.decryptStreamChunk(data, state));
diff --git a/web/packages/base/crypto/libsodium.ts b/web/packages/base/crypto/libsodium.ts
index 601bbeebd7..f2305398f3 100644
--- a/web/packages/base/crypto/libsodium.ts
+++ b/web/packages/base/crypto/libsodium.ts
@@ -36,7 +36,7 @@ export const toB64 = async (input: Uint8Array) => {
  *
  * This is the converse of {@link toBase64}.
  */
-export const fromB64 = async (input: string) => {
+export const fromB64 = async (input: string): Promise<Uint8Array> => {
     await sodium.ready;
     return sodium.from_base64(input, sodium.base64_variants.ORIGINAL);
 };
@@ -117,7 +117,7 @@ export const toHex = async (input: string) => {
  *
  * This is the inverse of {@link toHex}.
  */
-export const fromHex = async (input: string) => {
+export const fromHex = async (input: string): Promise<string> => {
     await sodium.ready;
     return await toB64(sodium.from_hex(input));
 };
@@ -478,7 +478,7 @@ export const encryptStreamChunk = async (
     data: Uint8Array,
     pushState: sodium.StateAddress,
     isFinalChunk: boolean,
-) => {
+): Promise<Uint8Array> => {
     await sodium.ready;
     const tag = isFinalChunk
         ? sodium.crypto_secretstream_xchacha20poly1305_TAG_FINAL
@@ -577,7 +577,7 @@ export const decryptMetadataJSON = async (
 export const decryptStreamBytes = async (
     { encryptedData, decryptionHeader }: EncryptedFile,
     key: BytesOrB64,
-) => {
+): Promise<Uint8Array> => {
     await sodium.ready;
     const pullState = sodium.crypto_secretstream_xchacha20poly1305_init_pull(
         await fromB64(decryptionHeader),
@@ -647,7 +647,7 @@ export const initChunkDecryption = async (
 export const decryptStreamChunk = async (
     data: Uint8Array,
     pullState: StateAddress,
-) => {
+): Promise<Uint8Array> => {
     await sodium.ready;
     const pullResult = sodium.crypto_secretstream_xchacha20poly1305_pull(
         pullState,