diff --git a/.drone.yml b/.drone.yml
index e721dda..8a3af4e 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -48,11 +48,11 @@ steps:
     source: https://cmake.org/files/v3.12/cmake-3.12.0-Linux-x86_64.sh
     destination: cmake_installer.sh
 
-- name: GCC 7 / clang 6
+- name: GCC 8 / clang 6
   image: ubuntu:bionic
   pull: always
   environment:
-    CXX: g++-7
+    CXX: g++-8
     CXXFLAGS: -pipe -O2
     DEBIAN_FRONTEND: noninteractive
     LANG: C.UTF-8
@@ -60,7 +60,7 @@ steps:
   - rm /etc/apt/apt.conf.d/docker-clean
   - alias apt-get='rm -f /var/cache/apt/archives/lock && apt-get'
   - apt-get update -q
-  - apt-get install -qq build-essential clang locales
+  - apt-get install -qq g++-8 build-essential clang locales
   - apt-get install -qq catch libboost-program-options-dev libboost-locale-dev libboost-regex-dev gettext libarchive-dev libfmt-dev asciidoc
   - sh cmake_installer.sh --skip-license --exclude-subdir --prefix=/usr/local
   - rm -rf build && mkdir -p build && cd build
diff --git a/README.adoc b/README.adoc
index 7359bd3..84f9caf 100644
--- a/README.adoc
+++ b/README.adoc
@@ -74,14 +74,14 @@ If you get the error message that `add-apt-repository` was not found, install
 ==== Dependencies
 
 * Tested OS: Linux
-* C\++ compiler with C++17 support (tested: link:{uri-gcc}[GCC] 7/10,
+* C\++ compiler with C++17 support (tested: link:{uri-gcc}[GCC] 8/10,
   link:{uri-clang}[clang] 6/11)
 * link:{uri-cmake}[CMake] (at least: 3.12)
 * link:{uri-boost}[Boost] (tested: 1.75.0 / 1.65.0)
 * link:{uri-gettext}[gettext] (tested: 0.21 / 0.19)
 * link:{uri-libarchive}[libarchive] (tested: 3.5 / 3.2)
 * link:{uri-fmt}[fmt] (tested: 7.0 / 4.0)
-* link:{uri-asciidoc}[AsciiDoc] (tested: 8.6 / 9.0)
+* link:{uri-asciidoc}[AsciiDoc] (tested: 9.0 / 8.6)
 * link:{uri-termcolor}[Termcolor] (tested: 2.0) (If not found, the bundled
   version is used.)
 * Optional