diff --git a/src/test/docker/bionic/Dockerfile b/src/test/docker/bionic/Dockerfile
index 7c6f3fba2fdf..c6f603f18247 100644
--- a/src/test/docker/bionic/Dockerfile
+++ b/src/test/docker/bionic/Dockerfile
@@ -19,7 +19,6 @@ RUN apt-get update \
         sudo \
         vim \
         luarocks \
-        ruby \
         munge \
         lcov \
         ccache \
@@ -61,7 +60,9 @@ RUN apt-get update \
         python3-wheel \
  && rm -rf /var/lib/apt/lists/* \
  && for PY in python3.6 python3.7 python3.8 ; do \
-        sudo $PY -m pip install --upgrade --ignore-installed coverage cffi six pyyaml jsonschema ; \
+        sudo $PY -m pip install --upgrade --ignore-installed \
+            coverage cffi six pyyaml jsonschema \
+            sphinx sphinx-rtd-theme sphinxcontrib-spelling; \
     done ; \
     apt-get -qq purge -y python3-pip \
  && apt-get -qq autoremove -y
@@ -90,6 +91,7 @@ RUN apt-get update \
         libfaketime \
         pylint \
         cppcheck \
+        enchant \
         aspell \
         aspell-en \
  && rm -rf /var/lib/apt/lists/*
@@ -99,9 +101,6 @@ RUN locale-gen en_US.UTF-8
 # NOTE: luaposix installed by rocks due to Ubuntu bug: #1752082 https://bugs.launchpad.net/ubuntu/+source/lua-posix/+bug/1752082
 RUN luarocks install luaposix
 
-# NOTE: we need asciidoctor 1.5.7 to handle manpages, install with gem install
-RUN /usr/bin/gem install asciidoctor
-
 # Install caliper by hand for now:
 RUN mkdir caliper \
  && cd caliper \
diff --git a/src/test/docker/centos7/Dockerfile b/src/test/docker/centos7/Dockerfile
index d09105afa1f6..8908ad3a6a58 100644
--- a/src/test/docker/centos7/Dockerfile
+++ b/src/test/docker/centos7/Dockerfile
@@ -51,11 +51,11 @@ RUN yum -y update \
       python36-six \
       python36-yaml \
       python36-jsonschema \
-      ruby \
       sqlite \
       valgrind \
       valgrind-devel \
       man-db \
+      enchant \
       aspell \
       aspell-en \
       devtoolset-7-make \
@@ -64,6 +64,9 @@ RUN yum -y update \
       libs3-devel \
  && yum clean all
 
+# Sphinx packages for docs
+RUN python3 -m pip install sphinx sphinx-rtd-theme sphinxcontrib-spelling
+
 # The cmake from yum is incredibly ancient, download a less ancient one
 RUN wget -q --no-check-certificate https://cmake.org/files/v3.10/cmake-3.10.1-Linux-x86_64.tar.gz\
  && tar -xzf cmake-3.10.1-Linux-x86_64.tar.gz\
@@ -71,8 +74,6 @@ RUN wget -q --no-check-certificate https://cmake.org/files/v3.10/cmake-3.10.1-Li
  && rm -rf cmake-3.10.1-Linux-x86_64\
  && rm cmake-3.10.1-Linux-x86_64.tar.gz
 
-RUN /usr/bin/gem install asciidoctor
-
 # Install caliper by hand for now:
 RUN mkdir caliper \
  && cd caliper \
diff --git a/src/test/docker/centos8/Dockerfile b/src/test/docker/centos8/Dockerfile
index dd8953c9f321..83f0246f428c 100644
--- a/src/test/docker/centos8/Dockerfile
+++ b/src/test/docker/centos8/Dockerfile
@@ -17,7 +17,6 @@ RUN yum -y install \
 	man-db \
 	git \
 	sudo \
-	ruby \
 	munge \
 	ccache \
 	lua \
@@ -40,7 +39,7 @@ RUN yum -y install \
 	gcc-c++ \
 	make \
 	cmake
-	
+
 #  Python
 RUN yum -y install \
 	python36 \
@@ -72,6 +71,7 @@ RUN yum -y install \
 	lua-posix \
 	libfaketime \
 	cppcheck \
+	enchant \
 	aspell \
 	aspell-en
 
@@ -84,7 +84,8 @@ RUN alternatives --set python /usr/bin/python3
 #  Add /usr/bin/mpicc link so MPI tests are built
 RUN alternatives --install /usr/bin/mpicc mpicc /usr/lib64/mpich/bin/mpicc 100
 
-RUN /usr/bin/gem install asciidoctor
+# Sphinx packages for docs
+RUN python3 -m pip install sphinx sphinx-rtd-theme sphinxcontrib-spelling
 
 # Install caliper by hand for now:
 RUN mkdir caliper \
diff --git a/src/test/docker/focal/Dockerfile b/src/test/docker/focal/Dockerfile
index 360659065b4a..cca8caa9f0fc 100644
--- a/src/test/docker/focal/Dockerfile
+++ b/src/test/docker/focal/Dockerfile
@@ -37,7 +37,6 @@ RUN apt-get update \
         lua-posix \
         mpich \
         valgrind \
-        asciidoctor \
         jq \
  && rm -rf /var/lib/apt/lists/*
 
@@ -70,6 +69,9 @@ RUN apt-get update \
         python3-jsonschema \
  && rm -rf /var/lib/apt/lists/*
 
+# Sphinx packages for docs
+RUN python3 -m pip install sphinx sphinx-rtd-theme sphinxcontrib-spelling
+
 # Other deps
 RUN apt-get update \
  && apt-get -qq install -y --no-install-recommends \
@@ -95,6 +97,7 @@ RUN apt-get update \
         libfaketime \
         pylint \
         cppcheck \
+        enchant \
         aspell \
         aspell-en \
  && rm -rf /var/lib/apt/lists/*