diff --git a/src/jwt.ts b/src/jwt.ts
index ac5ada4..967ef6f 100644
--- a/src/jwt.ts
+++ b/src/jwt.ts
@@ -10,7 +10,7 @@ export class JWTcontext {
 
   public static async gen_key(): Promise<Key> {
     log.trace('generate key')
-    return jose.generateSecret('HS512')
+    return await jose.generateSecret('HS512')
   }
   public static new(key: Key): JWTcontext {
     return new JWTcontext(key)
diff --git a/src/kdf.ts b/src/kdf.ts
index 9e3b52f..6e0826f 100644
--- a/src/kdf.ts
+++ b/src/kdf.ts
@@ -54,7 +54,7 @@ export async function hkdf(key: Uint8Array, usage: Usage): Promise<CryptoKey> {
   }
   const info = new TextEncoder().encode(info_txt)
 
-  return crypto.subtle.deriveKey(
+  return await crypto.subtle.deriveKey(
     {
       name: 'HKDF',
       hash: 'SHA-512',
@@ -86,10 +86,10 @@ export async function pbkdf(salt: Uint8Array, password: string): Promise<Uint8Ar
 
   return new Uint8Array(buffer)
 }
-export function ecdh(privkey: CryptoKey, pubkey: CryptoKey, usage: DHusage): Promise<CryptoKey> {
+export async function ecdh(privkey: CryptoKey, pubkey: CryptoKey, usage: DHusage): Promise<CryptoKey> {
   log.trace('ecdh')
   const outputUsage: KeyUsage[] = usage === DHusage.box ? ['encrypt', 'decrypt'] : ['wrapKey', 'unwrapKey']
-  return crypto.subtle.deriveKey(
+  return await crypto.subtle.deriveKey(
     {
       name: consts.ECDH.name,
       public: pubkey
diff --git a/src/private-box.ts b/src/private-box.ts
index 9207cfe..8f42dab 100644
--- a/src/private-box.ts
+++ b/src/private-box.ts
@@ -12,16 +12,9 @@ export default class PrivateBox {
     private readonly box: SecretBox
   ) {}
 
-  public static gen(extractable: boolean = true): Promise<CryptoKeyPair> {
+  public static async gen(extractable: boolean = true): Promise<CryptoKeyPair> {
     log.trace('generate keypair')
-    log.trace('Extractable :', extractable)
-    try {
-      return crypto.subtle.generateKey(consts.ECDH, extractable, ['deriveKey']) as Promise<CryptoKeyPair>
-    } catch (e) {
-      log.warn('Failed to generate a key')
-      log.debug('Error :', e)
-      throw e
-    }
+    return await crypto.subtle.generateKey(consts.ECDH, extractable, ['deriveKey']) as CryptoKeyPair
   }
 
   public static async encrypt(data: Uint8Array, pubkey: CryptoKey): Promise<PrivateBox> {
@@ -34,7 +27,7 @@ export default class PrivateBox {
   public async decrypt(privkey: CryptoKey): Promise<Uint8Array | null> {
     log.trace('decrypt')
     const key = await ecdh(privkey, this.pubkey, DHusage.box)
-    return this.box.decrypt(key)
+    return await this.box.decrypt(key)
   }
 
   public async toString(): Promise<string> {
@@ -57,10 +50,10 @@ export default class PrivateBox {
     return new PrivateBox(pubkey, box)
   }
 
-  public static pubkey_toString(pubkey: CryptoKey): Promise<string> {
-    return misc.pubkey_toString(pubkey)
+  public static async pubkey_toString(pubkey: CryptoKey): Promise<string> {
+    return await misc.pubkey_toString(pubkey)
   }
-  public static pubkey_fromString(pubkey: string): Promise<CryptoKey | null> {
-    return misc.pubkey_fromString(pubkey, misc.Usage.ecdh)
+  public static async pubkey_fromString(pubkey: string): Promise<CryptoKey | null> {
+    return await misc.pubkey_fromString(pubkey, misc.Usage.ecdh)
   }
 }
diff --git a/src/private-wrap.ts b/src/private-wrap.ts
index 662c09e..7b90ed4 100644
--- a/src/private-wrap.ts
+++ b/src/private-wrap.ts
@@ -12,9 +12,9 @@ export default class PrivateWrap {
     private readonly pubkey: CryptoKey
   ) {}
 
-  public static gen(extractable: boolean = true): Promise<CryptoKeyPair> {
+  public static async gen(extractable: boolean = true): Promise<CryptoKeyPair> {
     log.trace('generate keypair')
-    return crypto.subtle.generateKey(consts.ECDH, extractable, ['deriveKey']) as Promise<CryptoKeyPair>
+    return await crypto.subtle.generateKey(consts.ECDH, extractable, ['deriveKey']) as CryptoKeyPair
   }
 
   public static async wrap(data: CryptoKey, pubkey: CryptoKey): Promise<PrivateWrap> {
@@ -27,7 +27,7 @@ export default class PrivateWrap {
   public async unwrap(privkey: CryptoKey): Promise<CryptoKey | null> {
     log.trace('unwrap')
     const kd = await ecdh(privkey, this.pubkey, DHusage.wrap)
-    return this.box.unwrap(kd)
+    return await this.box.unwrap(kd)
   }
 
   public async toString(): Promise<string> {
@@ -50,10 +50,10 @@ export default class PrivateWrap {
     return new PrivateWrap(box, pubkey)
   }
 
-  public static pubkey_toString(pubkey: CryptoKey): Promise<string> {
-    return misc.pubkey_toString(pubkey)
+  public static async pubkey_toString(pubkey: CryptoKey): Promise<string> {
+    return await misc.pubkey_toString(pubkey)
   }
-  public static pubkey_fromString(pubkey: string): Promise<CryptoKey | null> {
-    return misc.pubkey_fromString(pubkey, misc.Usage.ecdh)
+  public static async pubkey_fromString(pubkey: string): Promise<CryptoKey | null> {
+    return await misc.pubkey_fromString(pubkey, misc.Usage.ecdh)
   }
 }
diff --git a/src/pwd-box.ts b/src/pwd-box.ts
index 569c3b4..09fc033 100644
--- a/src/pwd-box.ts
+++ b/src/pwd-box.ts
@@ -13,7 +13,7 @@ export default class PwdBox {
 
   private static async derive(pwd: string, salt: Uint8Array): Promise<CryptoKey> {
     const k = await pbkdf(salt, pwd)
-    return (await hkdf(k, Usage.box)) as CryptoKey
+    return await hkdf(k, Usage.box) as CryptoKey
   }
 
   public static async encrypt(data: Uint8Array, pwd: string): Promise<PwdBox> {
@@ -26,7 +26,7 @@ export default class PwdBox {
   public async decrypt(pwd: string): Promise<Uint8Array | null> {
     log.trace('decrypt')
     const k = await PwdBox.derive(pwd, this.salt)
-    return this.box.decrypt(k)
+    return await this.box.decrypt(k)
   }
 
   public toString(): string {
diff --git a/src/pwd-wrap.ts b/src/pwd-wrap.ts
index 5b6e94b..ce9d9a7 100644
--- a/src/pwd-wrap.ts
+++ b/src/pwd-wrap.ts
@@ -13,7 +13,7 @@ export default class PwdWrap {
 
   private static async derive(pwd: string, salt: Uint8Array): Promise<CryptoKey> {
     const k = await pbkdf(salt, pwd)
-    return (await hkdf(k, Usage.wrap)) as CryptoKey
+    return await hkdf(k, Usage.wrap) as CryptoKey
   }
 
   public static async wrap(data: CryptoKey, pwd: string, salt?: Uint8Array): Promise<PwdWrap> {
@@ -26,7 +26,7 @@ export default class PwdWrap {
   public async unwrap(pwd: string): Promise<CryptoKey | null> {
     log.trace('unwrap')
     const k = await PwdWrap.derive(pwd, this.salt)
-    return this.box.unwrap(k)
+    return await this.box.unwrap(k)
   }
 
   public toString(): string {
diff --git a/src/secret-box.ts b/src/secret-box.ts
index 8d70af2..065482a 100644
--- a/src/secret-box.ts
+++ b/src/secret-box.ts
@@ -10,9 +10,9 @@ export default class SecretBox {
     private readonly cipher: Uint8Array
   ) {}
 
-  public static gen(extractable: boolean = true): Promise<CryptoKey> {
+  public static async gen(extractable: boolean = true): Promise<CryptoKey> {
     log.trace('generate key')
-    return crypto.subtle.generateKey(
+    return await crypto.subtle.generateKey(
       {
         name: consts.ENCRYPTION,
         length: 256
diff --git a/src/secret-wrap.ts b/src/secret-wrap.ts
index 7e5e2da..e7e6a4c 100644
--- a/src/secret-wrap.ts
+++ b/src/secret-wrap.ts
@@ -13,9 +13,9 @@ export default class SecretWrap {
     private readonly iv: Uint8Array
   ) {}
 
-  public static gen(extractable: boolean = true): Promise<CryptoKey> {
+  public static async gen(extractable: boolean = true): Promise<CryptoKey> {
     log.trace('generate key')
-    return crypto.subtle.generateKey(
+    return await crypto.subtle.generateKey(
       {
         name: consts.ENCRYPTION,
         length: 256
diff --git a/src/signature.ts b/src/signature.ts
index a307d6e..e818ffb 100644
--- a/src/signature.ts
+++ b/src/signature.ts
@@ -5,7 +5,7 @@ import * as misc from './misc'
 import * as libmisc from 'misc'
 
 export async function gen(extractable: boolean = true): Promise<CryptoKeyPair> {
-  return crypto.subtle.generateKey(consts.SIGNATURE_KEY, extractable, ['sign', 'verify'])
+  return await crypto.subtle.generateKey(consts.SIGNATURE_KEY, extractable, ['sign', 'verify'])
 }
 export async function sign(message: Uint8Array, privkey: CryptoKey): Promise<Uint8Array> {
   log.trace('sign')
@@ -14,14 +14,14 @@ export async function sign(message: Uint8Array, privkey: CryptoKey): Promise<Uin
 }
 export async function verify(message: Uint8Array, pubkey: CryptoKey, signature: Uint8Array): Promise<boolean> {
   log.trace('verify')
-  return crypto.subtle.verify(consts.SIGNATURE_ALGO, pubkey, signature, message)
+  return await crypto.subtle.verify(consts.SIGNATURE_ALGO, pubkey, signature, message)
 }
 
-export function pubkey_toString(pubkey: CryptoKey): Promise<string> {
-  return misc.pubkey_toString(pubkey)
+export async function pubkey_toString(pubkey: CryptoKey): Promise<string> {
+  return await misc.pubkey_toString(pubkey)
 }
 export async function pubkey_fromString(pubkey: string): Promise<CryptoKey | null> {
-  return misc.pubkey_fromString(pubkey, misc.Usage.sign)
+  return await misc.pubkey_fromString(pubkey, misc.Usage.sign)
 }
 
 export function signature_toString(signature: Uint8Array): string {