diff --git a/Gemfile b/Gemfile
index 9b04095..cefa816 100644
--- a/Gemfile
+++ b/Gemfile
@@ -39,3 +39,5 @@ gem 'capistrano-git-with-submodules', '~> 2.0'
 gem "jekyll-paginate"
 
 gem 'ed25519', '~> 1.2', '>= 1.2.4'
+
+gem 'bcrypt_pbkdf', '~> 1.1'
diff --git a/Gemfile.lock b/Gemfile.lock
index 67409b5..0e631cc 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -5,6 +5,7 @@ GEM
       public_suffix (>= 2.0.2, < 5.0)
     airbrussh (1.4.0)
       sshkit (>= 1.6.1, != 1.7.0)
+    bcrypt_pbkdf (1.1.0)
     capistrano (3.16.0)
       airbrussh (>= 1.0.0)
       i18n
@@ -92,6 +93,7 @@ PLATFORMS
   x86_64-linux
 
 DEPENDENCIES
+  bcrypt_pbkdf (~> 1.1)
   capistrano (~> 3.10)
   capistrano-bundler
   capistrano-git-with-submodules (~> 2.0)