diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 8e8f47d..606010c 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -13,7 +13,10 @@ jobs:
         uses: xu-cheng/texlive-action/full@v1
         with:
           run: |
-            apk add make
+            apk add make zip tidyhtml
+            wget https://archive.org/download/kindlegen_linux_2_6_i386_v2_9/kindlegen_linux_2.6_i386_v2_9.tar.gz
+            tar xzf kindlegen_linux_2.6_i386_v2_9.tar.gz
+            mv kindlegen /usr/bin
             cd book
             make release
       - name: Release book on S3
@@ -23,4 +26,4 @@ jobs:
           aws_secret_access_key: ${{ secrets.AWS_SECRET_ACCESS_KEY}}
           aws_bucket: ${{ secrets.AWS_BUCKET }}
           source_dir: book/release
-          destination_dir: release
\ No newline at end of file
+          destination_dir: release
diff --git a/.github/workflows/validate.yml b/.github/workflows/validate.yml
index e8a8db6..961f399 100644
--- a/.github/workflows/validate.yml
+++ b/.github/workflows/validate.yml
@@ -13,3 +13,13 @@ jobs:
             apk add make
             cd book
             make build_pdf
+      - name: Test building release versions
+        uses: xu-cheng/texlive-action/full@v1
+        with:
+          run: |
+            apk add make zip tidyhtml
+            wget https://archive.org/download/kindlegen_linux_2_6_i386_v2_9/kindlegen_linux_2.6_i386_v2_9.tar.gz
+            tar xzf kindlegen_linux_2.6_i386_v2_9.tar.gz
+            mv kindlegen /usr/bin
+            cd book
+            make release