diff --git a/mrt-services/callback/.ruby-version b/mrt-services/callback/.ruby-version
new file mode 100644
index 0000000..351227f
--- /dev/null
+++ b/mrt-services/callback/.ruby-version
@@ -0,0 +1 @@
+3.2.4
diff --git a/mrt-services/callback/Gemfile.lock b/mrt-services/callback/Gemfile.lock
index b859e97..f4b44cc 100644
--- a/mrt-services/callback/Gemfile.lock
+++ b/mrt-services/callback/Gemfile.lock
@@ -48,6 +48,7 @@ GEM
     unicode-display_width (2.6.0)
 
 PLATFORMS
+  ruby
   x86_64-linux
 
 DEPENDENCIES
@@ -58,4 +59,4 @@ DEPENDENCIES
   thin
 
 BUNDLED WITH
-   2.2.33
+   2.6.2