diff --git a/README.md b/README.md
index d696cb1..518f329 100644
--- a/README.md
+++ b/README.md
@@ -247,3 +247,37 @@ serverless invoke stepf -n rBuilds -d '{"force": true}'
 # Rebuild specific R versions
 serverless invoke stepf -n rBuilds -d '{"force": true, "versions": ["3.6.3", "4.0.2"]}'
 ```
+
+## Testing
+
+To test the R builds locally, you can build the images:
+
+```bash
+# Build images for all platforms
+make docker-build
+
+# Or build the image for a single platform
+(cd builder && docker-compose build ubuntu-2004)
+```
+
+Then run the build script:
+
+```bash
+# Build R for all platforms
+R_VERSION=4.0.5 make docker-build-r
+
+# Build R for a single platform
+(cd builder && R_VERSION=4.0.5 docker-compose up ubuntu-2004)
+
+# Alternatively, run the build script from within a container
+docker run -it --rm --entrypoint "/bin/bash" r-builds:ubuntu-2004
+
+# Build R 4.0.5
+R_VERSION=4.0.5 ./build.sh
+
+# Build R devel
+R_VERSION=devel ./build.sh
+
+# Build a prerelease version of R (e.g., alpha or beta)
+R_VERSION=rc R_TARBALL_URL=https://cran.r-project.org/src/base-prerelease/R-latest.tar.gz ./build.sh
+```
diff --git a/builder/Dockerfile.opensuse-15 b/builder/Dockerfile.opensuse-15
index e2f6ea2..6cf0a7b 100644
--- a/builder/Dockerfile.opensuse-15
+++ b/builder/Dockerfile.opensuse-15
@@ -43,9 +43,11 @@ RUN zypper --non-interactive --gpg-auto-import-keys -n install \
     shadow \
     tcl-devel \
     texinfo \
+    texlive-ae \
     texlive-bibtex \
     texlive-cm-super \
     texlive-dvips \
+    texlive-fancyvrb \
     texlive-helvetic \
     texlive-inconsolata \
     texlive-latex \
diff --git a/builder/Dockerfile.opensuse-152 b/builder/Dockerfile.opensuse-152
index 66c94ed..6990536 100644
--- a/builder/Dockerfile.opensuse-152
+++ b/builder/Dockerfile.opensuse-152
@@ -43,9 +43,11 @@ RUN zypper --non-interactive --gpg-auto-import-keys -n install \
     shadow \
     tcl-devel \
     texinfo \
+    texlive-ae \
     texlive-bibtex \
     texlive-cm-super \
     texlive-dvips \
+    texlive-fancyvrb \
     texlive-helvetic \
     texlive-inconsolata \
     texlive-latex \
diff --git a/builder/Dockerfile.opensuse-42 b/builder/Dockerfile.opensuse-42
index f7f9435..b98f498 100644
--- a/builder/Dockerfile.opensuse-42
+++ b/builder/Dockerfile.opensuse-42
@@ -35,8 +35,6 @@ RUN zypper --non-interactive --gpg-auto-import-keys -n install \
     pcre2-devel \
     perl \
     perl-macros \
-    python \
-    python-pip \
     readline-devel \
     rpm-build \
     ruby \
@@ -44,9 +42,11 @@ RUN zypper --non-interactive --gpg-auto-import-keys -n install \
     shadow \
     tcl-devel \
     texinfo \
+    texlive-ae \
     texlive-bibtex \
     texlive-cm-super \
     texlive-dvips \
+    texlive-fancyvrb \
     texlive-helvetic \
     texlive-inconsolata \
     texlive-latex \
@@ -64,7 +64,10 @@ RUN zypper --non-interactive --gpg-auto-import-keys -n install \
     zlib-devel \
     && zypper clean
 
-RUN pip install awscli
+RUN curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip" && \
+    unzip awscliv2.zip && \
+    ./aws/install && \
+    rm -rf aws awscliv2.zip
 
 # Pin fpm for compatibility with Ruby < 2.3
 RUN gem install ffi:1.12.2 fpm:1.11.0 && \
diff --git a/builder/build.sh b/builder/build.sh
index 2e43653..8f77a36 100755
--- a/builder/build.sh
+++ b/builder/build.sh
@@ -40,7 +40,10 @@ archive_r() {
 
 fetch_r_source() {
   echo "Downloading R-${1}"
-  if [ "${1}" = devel ]; then
+  if [ -n "${R_TARBALL_URL}" ]; then
+    # Custom tarball URL for testing (e.g., R alpha and beta releases)
+    wget -q "${R_TARBALL_URL}" -O /tmp/R-${1}.tar.gz
+  elif [ "${1}" = devel ]; then
     # Download the daily tarball of R devel
     wget -q https://stat.ethz.ch/R/daily/R-devel.tar.gz -O /tmp/R-devel.tar.gz
   else