diff --git a/.github/workflows/run-tests.yml b/.github/workflows/run-tests.yml
index 29a5605d..979fccb1 100644
--- a/.github/workflows/run-tests.yml
+++ b/.github/workflows/run-tests.yml
@@ -10,13 +10,13 @@ jobs:
       fail-fast: false
       matrix:
         # https://endoflife.date/ruby
-        ruby: ["2.7", "3.0", "3.1", "3.2"]
-        vault: ["1.11.9", "1.12.5", "1.13.1"]
+        ruby: ["2.7", "3.0", "3.1", "3.2", "3.3", "3.4"]
+        vault: ["1.16.3", "1.19.5", "1.20.4", "1.21.1"]
     runs-on: ubuntu-latest
     timeout-minutes: 5
     steps:
-      - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
-      - uses: ruby/setup-ruby@22fdc77bf4148f810455b226c90fb81b5cbc00a7 # v1.171.0
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - uses: ruby/setup-ruby@32110d4e311bd8996b2a82bf2a43b714ccc91777 # v1.221.0
         with:
           ruby-version: ${{ matrix.ruby }}
           bundler-cache: true # runs 'bundle install' and caches installed gems automatically
diff --git a/vault.gemspec b/vault.gemspec
index be53ac82..f9f112bb 100644
--- a/vault.gemspec
+++ b/vault.gemspec
@@ -26,6 +26,7 @@ Gem::Specification.new do |spec|
     spec.add_runtime_dependency "aws-eventstream", "= 1.2.0"
   else
     spec.add_runtime_dependency "aws-sigv4"
+    spec.add_runtime_dependency "base64"
   end
 
   spec.add_development_dependency "bundler", "~> 2"