diff --git a/.travis.yml b/.travis.yml
index b06bc447bd..c2bd765963 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -341,6 +341,79 @@ _matrix_linux_gnustd_nowarn:
         packages:
         - *deps_driverlibs
 
+# Try s390x builds to check for issues with endianness
+# (it is one current Travis offer with BigEndian CPUs)
+_matrix_linux_gnustd_nowarn_s390x_64bit_viable:
+  include: &_matrix_linux_gnustd_nowarn_s390x_64bit_viable
+  - env: NUT_MATRIX_TAG="gnu99-gcc-default-nowarn-s390x-64bit" BUILD_TYPE=default-all-errors CFLAGS="-std=gnu99" CXXFLAGS="-std=gnu++98"
+    os: linux
+    arch: s390x
+    sudo: false
+    services:
+        - docker
+    compiler: gcc
+    addons:
+      apt:
+        packages:
+        - *deps_driverlibs
+        - time
+
+  - env: NUT_MATRIX_TAG="gnu17-gcc-9-nowarn-s390x-64bit" BUILD_TYPE=default-all-errors CFLAGS="-std=gnu17" CXXFLAGS="-std=gnu++17" CC=gcc-9 CXX=g++-9
+    os: linux
+    arch: s390x
+    sudo: false
+    services:
+        - docker
+    compiler: gcc
+    addons:
+      apt:
+        sources:
+        - ubuntu-toolchain-r-test
+        packages:
+        - g++-9
+        - gcc-9
+        - *deps_driverlibs
+        - time
+
+  - env: NUT_MATRIX_TAG="gnu17-clang-8-nowarn-s390x-64bit" BUILD_TYPE=default-all-errors CFLAGS="-std=gnu17" CXXFLAGS="-std=gnu++17" CC=clang-8 CXX=clang++-8
+    os: linux
+    arch: s390x
+    dist: xenial
+    sudo: false
+    services:
+        - docker
+    compiler: clang
+    if: branch =~ fightwarn
+    addons:
+      apt:
+        sources:
+        - llvm-toolchain-xenial-8
+        packages:
+        - clang-8
+        - clang-format-8
+        - *deps_driverlibs
+
+_matrix_linux_gnustd_nowarn_s390x_64bit_fatal:
+  include: &_matrix_linux_gnustd_nowarn_s390x_64bit_fatal
+  - env: NUT_MATRIX_TAG="gnu17-clang-8-warn-s390x-64bit" BUILD_TYPE=default-all-errors CFLAGS="-Wall -Wextra -Werror -Weverything -Wno-unused-macros -Wno-reserved-id-macro -Wno-padded -pedantic -std=gnu17" CXXFLAGS="-Wall -Wextra -Werror -Weverything -Wno-unused-macros -Wno-reserved-id-macro -Wno-padded -std=gnu++17" CC=clang-8 CXX=clang++-8
+    os: linux
+    arch: s390x
+    dist: xenial
+    sudo: false
+    services:
+        - docker
+    compiler: clang
+    if: branch =~ fightwarn
+    addons:
+      apt:
+        sources:
+        - llvm-toolchain-xenial-8
+        packages:
+        - clang-8
+        - clang-format-8
+        - *deps_driverlibs
+        - time
+
 # Try ARM builds to check for issues with non-x86 CPUs
 _matrix_linux_gnustd_nowarn_arm_64bit_viable:
   include: &_matrix_linux_gnustd_nowarn_arm_64bit_viable
@@ -907,6 +980,7 @@ _matrix_required_linux:
   - *_matrix_linux_gnustd_nowarn
   - *_matrix_linux_gnustd_warn_viable
   - *_matrix_linux_gnustd_nowarn_arm_64bit_viable
+  - *_matrix_linux_gnustd_nowarn_s390x_64bit_viable
 
 _matrix_linux_gnustd_warn:
   include: &_matrix_linux_gnustd_warn
@@ -919,6 +993,7 @@ _matrix_allowfail_linux:
   - *_matrix_linux_gnustd_warn_fatal
   - *_matrix_linux_cstd_warn
   - *_matrix_linux_gnustd_nowarn_arm_64bit_fatal
+  - *_matrix_linux_gnustd_nowarn_s390x_64bit_fatal
 
 _matrix_linux_gnustd_nowarn_arm_64bit:
   include: &_matrix_linux_gnustd_nowarn_arm_64bit
@@ -929,6 +1004,15 @@ _matrix_linux_arm:
   include: &_matrix_linux_arm
   - *_matrix_linux_gnustd_nowarn_arm_64bit
 
+_matrix_linux_gnustd_nowarn_s390x_64bit:
+  include: &_matrix_linux_gnustd_nowarn_s390x_64bit
+  - *_matrix_linux_gnustd_nowarn_s390x_64bit_viable
+  - *_matrix_linux_gnustd_nowarn_s390x_64bit_fatal
+
+_matrix_linux_s390x:
+  include: &_matrix_linux_s390x
+  - *_matrix_linux_gnustd_nowarn_s390x_64bit
+
 _matrix_linux:
   include: &_matrix_linux
   - *_matrix_required_linux
@@ -999,6 +1083,8 @@ _matrix_gnustd_nowarn:
 #  -*_matrix_windows_gnustd_nowarn
   - *_matrix_linux_gnustd_nowarn_arm_64bit_viable
   - *_matrix_linux_gnustd_nowarn_arm_64bit_fatal
+  - *_matrix_linux_gnustd_nowarn_s390x_64bit_viable
+  - *_matrix_linux_gnustd_nowarn_s390x_64bit_fatal
 
 _matrix_warn:
   include: &_matrix_warn
@@ -1087,6 +1173,12 @@ jobs:
   - env: NUT_MATRIX_TAG="c89-gcc-default-warn" BUILD_TYPE=default-all-errors CFLAGS="-Wall -Wextra -Werror -pedantic -std=c89" CXXFLAGS="-Wall -Wextra -Werror -std=c++89"
   - env: NUT_MATRIX_TAG="gnu89-gcc-default-warn" BUILD_TYPE=default-all-errors CFLAGS="-Wall -Wextra -Werror -pedantic -std=gnu89" CXXFLAGS="-Wall -Wextra -Werror -std=gnu++89"
 
+### Linux on s390x (BigEndian)
+#OK#  - env: NUT_MATRIX_TAG="gnu99-gcc-default-nowarn-s390x-64bit" BUILD_TYPE=default-all-errors CFLAGS="-std=gnu99" CXXFLAGS="-std=gnu++98"
+#OK#  - env: NUT_MATRIX_TAG="gnu17-gcc-9-nowarn-s390x-64bit" BUILD_TYPE=default-all-errors CFLAGS="-std=gnu17" CXXFLAGS="-std=gnu++17" CC=gcc-9 CXX=g++-9
+#OK#  - env: NUT_MATRIX_TAG="gnu17-clang-8-nowarn-s390x-64bit" BUILD_TYPE=default-all-errors CFLAGS="-std=gnu17" CXXFLAGS="-std=gnu++17" CC=clang-8 CXX=clang++-8
+  - env: NUT_MATRIX_TAG="gnu17-clang-8-warn-s390x-64bit" BUILD_TYPE=default-all-errors CFLAGS="-Wall -Wextra -Werror -Weverything -Wno-unused-macros -Wno-reserved-id-macro -Wno-padded -pedantic -std=gnu17" CXXFLAGS="-Wall -Wextra -Werror -Weverything -Wno-unused-macros -Wno-reserved-id-macro -Wno-padded -std=gnu++17" CC=clang-8 CXX=clang++-8
+
 ### Linux on ARM
 #OK#  - env: NUT_MATRIX_TAG="gnu99-gcc-default-nowarn-ARM-64bit" BUILD_TYPE=default-all-errors CFLAGS="-std=gnu99" CXXFLAGS="-std=gnu++98"
 #OK#  - env: NUT_MATRIX_TAG="gnu17-gcc-9-nowarn-ARM-64bit" BUILD_TYPE=default-all-errors CFLAGS="-std=gnu17" CXXFLAGS="-std=gnu++17" CC=gcc-9 CXX=g++-9