diff --git a/src/index.js b/src/index.js
index 6f1ad0b..380ecdd 100644
--- a/src/index.js
+++ b/src/index.js
@@ -5,6 +5,8 @@ const protobuf = require('protocol-buffers')
 const pbm = protobuf(require('./crypto.proto'))
 const c = require('./crypto')
 
+exports.protobuf = pbm
+
 exports.hmac = c.hmac
 exports.aes = c.aes
 exports.webcrypto = c.webcrypto