diff --git a/.github/workflows/solaris.yml b/.github/workflows/solaris.yml
new file mode 100644
index 00000000000..b1adfcbed6c
--- /dev/null
+++ b/.github/workflows/solaris.yml
@@ -0,0 +1,55 @@
+name: Run Solaris tests
+
+# This test runs within a Solaris VM.
+# It is very slow.
+# Consequently, we only want to run it on demand.
+# The trigger is the feature branch name.
+
+on:
+  push:
+    branches:
+      - '*sun*'
+      - '*Sun*'
+      - '*solaris*'
+      - '*Solaris*'
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    name: solaris-vm test
+    env:
+      EX_TOKEN: "ex_value"
+    steps:
+    - uses: actions/checkout@v4
+    - name: Test in Solaris
+      id: test
+      uses: vmactions/solaris-vm@v1.0.1
+      with:
+        envs: 'EX_TOKEN'
+        usesh: true
+        prepare: |
+          pkgutil -y -i socat
+        release: "11.4-gcc"
+        run: |
+          if [ -n "test" ]; then
+            echo "false"
+          fi
+          if [ "test" ]; then
+            echo "test"
+          fi
+          pwd
+          ls -lah
+          whoami
+          env
+          psrinfo -vp
+          cat /etc/release
+          psrinfo -v
+          echo "::memstat" | mdb -k
+          gcc -v
+          CC=gcc CFLAGS="-Werror -O1" gmake -j check
+          pkg install cmake
+          cmake --version
+          rm -rf cmakebuild install
+          mkdir -p cmakebuild install
+          cd cmakebuild; cmake -Wdev -DCMAKE_BUILD_TYPE=Debug -DCMAKE_C_FLAGS="-Werror -O0" -DCMAKE_INSTALL_PREFIX=install ../build/cmake; cd ..
+          cmake --build cmakebuild --target install -- -j V=1
diff --git a/build/cmake/CMakeLists.txt b/build/cmake/CMakeLists.txt
index 023b998f556..155f3112d7b 100644
--- a/build/cmake/CMakeLists.txt
+++ b/build/cmake/CMakeLists.txt
@@ -34,7 +34,6 @@ project(zstd
   VERSION "${zstd_VERSION_MAJOR}.${zstd_VERSION_MINOR}.${zstd_VERSION_PATCH}"
   LANGUAGES C   # Main library is in C
             ASM # And ASM
-            CXX # Testing contributed code also utilizes CXX
   )
 
 message(STATUS "ZSTD VERSION: ${zstd_VERSION}")
diff --git a/build/cmake/CMakeModules/AddZstdCompilationFlags.cmake b/build/cmake/CMakeModules/AddZstdCompilationFlags.cmake
index 5f179989b68..5a0fd8199d2 100644
--- a/build/cmake/CMakeModules/AddZstdCompilationFlags.cmake
+++ b/build/cmake/CMakeModules/AddZstdCompilationFlags.cmake
@@ -51,7 +51,7 @@ function(EnableCompilerFlag _flag _C _CXX _LD)
 endfunction()
 
 macro(ADD_ZSTD_COMPILATION_FLAGS)
-    if (CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang" OR MINGW) #Not only UNIX but also WIN32 for MinGW
+    if (CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang" OR MINGW) # Not only UNIX but also WIN32 for MinGW
         # It's possible to select the exact standard used for compilation.
         # It's not necessary, but can be employed for specific purposes.
         # Note that zstd source code is compatible with both C++98 and above
diff --git a/build/cmake/contrib/CMakeLists.txt b/build/cmake/contrib/CMakeLists.txt
index 8df2a17b3a8..48201f770a5 100644
--- a/build/cmake/contrib/CMakeLists.txt
+++ b/build/cmake/contrib/CMakeLists.txt
@@ -7,7 +7,11 @@
 # in the COPYING file in the root directory of this source tree).
 # ################################################################
 
-project(contrib)
+project(contrib
+  LANGUAGES C   # Main library is in C
+  ASM # And ASM
+  CXX # pzstd, gen_html
+)
 
 add_subdirectory(pzstd)
 add_subdirectory(gen_html)