diff --git a/.github/workflows/clang-format-check.yml b/.github/workflows/clang-format-check.yml
index a6a3dfe..4004e56 100644
--- a/.github/workflows/clang-format-check.yml
+++ b/.github/workflows/clang-format-check.yml
@@ -21,6 +21,6 @@ jobs:
     - name: Run clang-format style check for C/C++/Protobuf programs.
       uses: jidicula/clang-format-action@v4.11.0
       with:
-        clang-format-version: '16'
+        clang-format-version: '17'
         check-path: ${{ matrix.path }}
         fallback-style: 'LLVM' # optional
diff --git a/.github/workflows/cpp-linux-build.yml b/.github/workflows/cpp-linux-build.yml
index f23cb1a..d106edd 100644
--- a/.github/workflows/cpp-linux-build.yml
+++ b/.github/workflows/cpp-linux-build.yml
@@ -24,9 +24,19 @@ jobs:
     - name: "Test"
       run: ctest --test-dir build
     
+    - name: "prepare build (debug), gcc"
+      run: cmake -S . -B build -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Debug
+    - name: "build"
+      run: cmake --build build --target all --config Debug -- -j4
+    
     - name: "prepare build (production/standard), clang++"
       run: cmake -S . -B build -G "Unix Makefiles" -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_BUILD_TYPE=Release
     - name: "build"
       run: cmake --build build --target all --config Release -- -j4
     - name: "Test"
       run: ctest --test-dir build
+    
+    - name: "prepare build (debug), clang++"
+      run: cmake -S . -B build -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=Debug -DCMAKE_CXX_COMPILER=clang++
+    - name: "build"
+      run: cmake --build build --target all --config Debug -- -j4
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index ef747cf..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,22 +0,0 @@
-language: c++
-dist: bionic
-compiler:
-  - gcc
-  - clang
-
-before_install:
-  - sudo apt-get install -y scons
-  - sudo apt-get install -y libboost-all-dev
-
-defore_script:
-  - git clone https://github.com/xanthospap/ggdatetime.git && cd ggdatetime
-  - sudo scons install
-  - cd ../
-  - git clone https://github.com/xanthospap/matvec.git && cd matvec
-  - sudo scons install
-  - cd ../
-  - sudo ldconfig
-
-script:
-  - scons
-  - scons debug=1