diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index e0d310ffa..d4c75d903 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -38,13 +38,26 @@ jobs:
       matrix:
         ruby: ${{ fromJSON(needs.rubocop_and_matrix.outputs.ruby) }}
         include:
-          - ruby: 'jruby-9.4.12.1'
-          - ruby: 'jruby-10.0.2.0'
+          - ruby: 'jruby-9.4.12.1' # used in OpenVox 8
+          - ruby: 'jruby-10.0.5.0' # latest JRuby for Ruby 3.4 compatibility / OpenVox 9 target version
     runs-on: ubuntu-24.04
     steps:
       - name: Checkout current PR
         uses: actions/checkout@v6
-
+      # we explictly force Java 17 because that's the lowest one we support when building packages with ezbake
+      - name: Set up Java 17 for JRuby 9
+        if: contains(matrix.ruby, 'jruby-9')
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '17'
+      # JRuby 10.0.5 requires java 21 or 25
+      - name: Set up Java 21 for JRuby 10
+        if: contains(matrix.ruby, 'jruby-10')
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '21'
       - name: Rspec checks
         uses: ruby/setup-ruby@v1
         with:
@@ -140,7 +153,7 @@ jobs:
           - {os: ubuntu-22.04, ruby: '3.2'} # with openssl 3
           - {os: ubuntu-22.04, ruby: 'jruby-9.3.14.0'}
           - {os: ubuntu-latest, ruby: 'jruby-9.4.12.1'}
-          - {os: ubuntu-latest, ruby: 'jruby-10.0.2.0'}
+          - {os: ubuntu-latest, ruby: 'jruby-10.0.5.0'}
           - {os: windows-2022, ruby: '2.7'}
           - {os: windows-2022, ruby: '3.2'} # with openssl 3
     runs-on: ${{ matrix.cfg.os }}