diff --git a/.github/workflows/build-containers.yml b/.github/workflows/build-containers.yml
index f007f8f..8bb3d5f 100644
--- a/.github/workflows/build-containers.yml
+++ b/.github/workflows/build-containers.yml
@@ -25,17 +25,12 @@ jobs:
       matrix:
         container:
           - 'centos-7-amd64'
-          - 'centos-8-amd64'
           - 'centos-9-amd64'
-          - 'fedora-35-amd64'
-          - 'fedora-36-amd64'
-          - 'fedora-38-amd64'
           - 'fedora-39-amd64'
           - 'fedora-40-amd64'
           - 'debian-11-amd64'
-          - 'debian-12-amd64'
           - 'debian-11-i386'
-          - 'debian-10-i386'
+          - 'debian-12-amd64'
           - 'debian-12-i386'
           - 'opensuse-leap'
           - 'opensuse-tumbleweed'
diff --git a/centos-8-amd64.Dockerfile b/centos-8-amd64.Dockerfile
deleted file mode 100644
index d03e7fc..0000000
--- a/centos-8-amd64.Dockerfile
+++ /dev/null
@@ -1,34 +0,0 @@
-FROM tgagor/centos:stream8
-
-ENV LANG=C.UTF-8
-ENV LC_ALL=C.UTF-8
-ENV LC_LANG=C.UTF-8
-ENV ARCH=x64
-ENV CPU=x86_64
-ENV OS=linux
-# CXXFLAGS environment setting resolves dual ABI issues caused by BOTAN libraries with the version of GCC installed at 'tgagor/centos:stream8'
-# https://gcc.gnu.org/onlinedocs/gcc-5.2.0/libstdc++/manual/manual/using_dual_abi.html
-ENV CXXFLAGS=-D_GLIBCXX_USE_CXX11_ABI=0
-# For libiconv
-ENV LD_LIBRARY_PATH=/usr/local/lib
-
-ARG CC=gcc
-ARG CXX=g++
-
-COPY tools /opt/tools
-
-RUN dnf -y update && dnf -y install sudo wget git epel-release 'dnf-command(config-manager)'         && \
-    dnf config-manager --set-enabled powertools                                                      && \
-    rpm --import https://github.com/riboseinc/yum/raw/master/ribose-packages.pub                     && \
-    rpm --import https://github.com/riboseinc/yum/raw/master/ribose-packages-next.pub                && \
-    wget https://github.com/riboseinc/yum/raw/master/ribose.repo -O /etc/yum.repos.d/ribose.repo     && \
-    dnf -y install json-c-devel clang gcc gcc-c++ make autoconf libtool gzip bzip2 bzip2-devel          \
-                   gettext-devel ncurses-devel zlib-devel python3 asciidoctor                           \
-                   openssl-devel bison byacc cmake gpg botan2 botan2-devel perl-Digest-SHA
-
-RUN /opt/tools/tools.sh ensure_symlink_to_target '/usr/bin/python3' '/usr/bin/python' && \
-    /opt/tools/tools.sh build_and_install_automake                                    && \
-    /opt/tools/tools.sh build_and_install_libiconv                                    && \
-    /opt/tools/tools.sh build_and_install_gpg lts                                     && \
-    /opt/tools/tools.sh build_and_install_gpg stable                                  && \
-    /opt/tools/tools.sh build_and_install_botan 2.18.2
diff --git a/fedora-35-amd64.Dockerfile b/fedora-35-amd64.Dockerfile
deleted file mode 100644
index f66345c..0000000
--- a/fedora-35-amd64.Dockerfile
+++ /dev/null
@@ -1,25 +0,0 @@
-FROM fedora:35
-
-ENV LANG=C.UTF-8
-ENV LC_ALL=C.UTF-8
-ENV LC_LANG=C.UTF-8
-ENV ARCH=x64
-ENV CPU=x86_64
-ENV OS=linux
-# For libiconv
-ENV LD_LIBRARY_PATH=/usr/local/lib
-
-ARG CC=gcc
-ARG CXX=g++
-
-COPY tools /opt/tools
-
-RUN dnf -y update                                                                                 && \
-    dnf -y install sudo wget git openssl-devel bison byacc cmake python perl-Digest-SHA              \
-                   json-c-devel clang gcc gcc-c++ make autoconf libtool gzip bzip2 bzip2-devel       \
-                   gettext-devel ncurses-devel zlib-devel asciidoctor botan2 botan2-devel
-
-RUN /opt/tools/tools.sh build_and_install_automake                                                 && \
-    /opt/tools/tools.sh build_and_install_libiconv                                                 && \
-    /opt/tools/tools.sh build_and_install_gpg lts                                                  && \
-    /opt/tools/tools.sh build_and_install_gpg stable
diff --git a/fedora-36-amd64.Dockerfile b/fedora-36-amd64.Dockerfile
deleted file mode 100644
index 0e583f4..0000000
--- a/fedora-36-amd64.Dockerfile
+++ /dev/null
@@ -1,27 +0,0 @@
-FROM fedora:36
-
-ENV LANG=C.UTF-8
-ENV LC_ALL=C.UTF-8
-ENV LC_LANG=C.UTF-8
-ENV ARCH=x64
-ENV CPU=x86_64
-ENV OS=linux
-# For libiconv
-ENV LD_LIBRARY_PATH=/usr/local/lib
-
-ARG CC=gcc
-ARG CXX=g++
-
-COPY tools /opt/tools
-
-RUN dnf -y update                                                                                 && \
-    dnf -y install sudo wget git openssl-devel bison byacc cmake python perl-Digest-SHA              \
-                   json-c-devel clang gcc gcc-c++ make autoconf libtool gzip bzip2 bzip2-devel       \
-                   gettext-devel ncurses-devel zlib-devel asciidoctor botan2 botan2-devel llvm
-
-RUN /opt/tools/tools.sh build_and_install_libiconv                                                  && \
-    /opt/tools/tools.sh build_and_install_gpg lts                                                   && \
-    /opt/tools/tools.sh build_and_install_gpg stable                                                && \
-    /opt/tools/tools.sh build_and_install_botan 3.1.1                                               && \
-    /opt/tools/tools.sh build_and_install_botan 3.2.0                                               && \
-    /opt/tools/tools.sh build_and_install_botan 3.3.0
diff --git a/fedora-38-amd64.Dockerfile b/fedora-38-amd64.Dockerfile
deleted file mode 100644
index 1d0cf7d..0000000
--- a/fedora-38-amd64.Dockerfile
+++ /dev/null
@@ -1,25 +0,0 @@
-FROM fedora:38
-
-ENV LANG=C.UTF-8
-ENV LC_ALL=C.UTF-8
-ENV LC_LANG=C.UTF-8
-ENV ARCH=x64
-ENV CPU=x86_64
-ENV OS=linux
-# For libiconv
-ENV LD_LIBRARY_PATH=/usr/local/lib
-
-ARG CC=gcc
-ARG CXX=g++
-
-COPY tools /opt/tools
-
-RUN dnf -y update                                                                                 && \
-    dnf -y install sudo wget git openssl-devel bison byacc cmake python perl-Digest-SHA              \
-                   json-c-devel clang gcc gcc-c++ make autoconf libtool gzip bzip2 bzip2-devel       \
-                   gettext-devel ncurses-devel zlib-devel asciidoctor botan2 botan2-devel llvm
-
-RUN /opt/tools/tools.sh build_and_install_libiconv                                                  && \
-    /opt/tools/tools.sh build_and_install_gpg lts                                                   && \
-    /opt/tools/tools.sh build_and_install_gpg stable                                                && \
-    /opt/tools/tools.sh build_and_install_botan 3.4.0