diff --git a/Containerfile b/Containerfile
index 3c17cb9bfb..65b529c6be 100644
--- a/Containerfile
+++ b/Containerfile
@@ -52,7 +52,6 @@ RUN set -x \
     nodejs \
     python3-pip \
     rsync \
-    rubygem-bundler \
     shyaml \
     tar \
     tox \
@@ -64,7 +63,6 @@ RUN set -x \
     && dnf clean all --quiet \
     && dot -v \
     && node --version \
-    && ruby --version \
     && vale --version
 
 # Install Python packages
@@ -74,13 +72,6 @@ RUN set -x \
     yq \
     && yq --version
 
-# Install Ruby packages (requires Ruby 2.7)
-RUN set -x \
-    && gem install asciidoctor-pdf \
-    && which asciidoctor-pdf \
-    && asciidoctor --version \
-    && asciidoctor-pdf --version
-
 # WORKDIR is a Node.js prerequisite
 WORKDIR /tmp
 # Avoid error: Local gulp not found in /projects
@@ -96,6 +87,7 @@ RUN set -x \
     && npm install --no-save --global asciidoctor-kroki \
     && npm install --no-save --global gulp gulp-cli gulp-connect \
     && npm install --no-save --global js-yaml \
+    && npm install --no-save --global asciidoctor \
     && which antora \
     && antora --version \
     && rm /tmp/* --recursive --force
@@ -112,7 +104,6 @@ WORKDIR /projects
 RUN set -x \
     && antora --version \
     && asciidoctor --version \
-    && asciidoctor-pdf --version \
     && bash --version \
     && curl --version \
     && git --version \
diff --git a/antora-assembler.yml b/antora-assembler.yml
index e724044b01..dfc09607c7 100644
--- a/antora-assembler.yml
+++ b/antora-assembler.yml
@@ -14,5 +14,5 @@ root_level: 1
 component_versions: '*'
 section_merge_strategy: fuse
 build:
-    command: asciidoctor-pdf --attribute toclevels=5 --attribute antora-assembler=true --trace --sourcemap
+    command: asciidoctor --attribute toclevels=5 --attribute antora-assembler=true --trace
     keep_aggregate_source: true