diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index e2ad38c..8a6b537 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -1,7 +1,5 @@
 name: Run Tests
-
 on: push
-
 jobs:
   test:
     runs-on: ubuntu-latest
@@ -11,10 +9,10 @@ jobs:
         run: cat env.example env.development > .env
       - name: Load .env file
         uses: xom9ikk/dotenv@v2
-      - name: Set up Ruby 3.4
+      - name: Set up Ruby 4.0
         uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 3.4
+          ruby-version: 4.0
           bundler-cache: true
       - name: Run linter for Ruby
         run: bundle exec standardrb
diff --git a/Dockerfile b/Dockerfile
index 6cdd936..a3808fe 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:3.4 AS development
+FROM ruby:4.0 AS development
 
 ARG UNAME=app
 ARG UID=1000
diff --git a/Gemfile b/Gemfile
index 3cb4e0c..855e211 100644
--- a/Gemfile
+++ b/Gemfile
@@ -20,6 +20,7 @@ gem "yabeda-prometheus"
 gem "canister"
 gem "semantic_logger"
 gem "milemarker", "~> 1.0"
+gem "ostruct"
 
 group :development, :test do
   gem "standard"
diff --git a/Gemfile.lock b/Gemfile.lock
index cbb86b6..1784c97 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -87,7 +87,7 @@ GEM
       logger
     faraday-net_http (3.4.2)
       net-http (~> 0.5)
-    faraday-retry (2.3.2)
+    faraday-retry (2.4.0)
       faraday (~> 2.0)
     hanami-cli (2.3.5)
       bundler (>= 2.1)
@@ -120,13 +120,16 @@ GEM
     method_source (1.1.0)
     milemarker (1.0.2)
       logger
-    minitest (5.26.0)
+    minitest (6.0.3)
+      drb (~> 2.0)
+      prism (~> 1.5)
     mysql2 (0.5.7)
       bigdecimal
     net-http (0.9.1)
       uri (>= 0.11.1)
     nokogiri (1.19.1-x86_64-linux-gnu)
       racc (~> 1.4)
+    ostruct (0.6.3)
     parallel (1.27.0)
     parser (3.3.10.2)
       ast (~> 2.4.1)
@@ -269,6 +272,7 @@ DEPENDENCIES
   climate_control
   hathifiles_database!
   milemarker (~> 1.0)
+  ostruct
   pry
   pry-byebug
   rspec