diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
index e9e693e57c3..786ae453370 100644
--- a/.github/workflows/macos.yml
+++ b/.github/workflows/macos.yml
@@ -23,6 +23,7 @@ jobs:
     runs-on: macos-14
     env:
       PYTHONWARNINGS: always
+      # LLVM_PROFILE_FILE: "grass-prof-%9m.profraw"
     steps:
       - name: Info
         run: |
@@ -55,8 +56,17 @@ jobs:
       - name: Prepare Conda environment file
         env:
           test_dependencies: |
+            compiler-rt
+            coverage
             ipython
+            libllvm20
+            lit
+            llvm
+            llvm-tools
+            llvm-tools-20
+            llvmdev
             pytest
+            pytest-cov
             pytest-github-actions-annotate-failures
             pytest-timeout
             pytest-xdist
@@ -72,7 +82,8 @@ jobs:
           environment-name: grass-env
           # Persist on the same period (date).
           cache-environment-key: environment-${{ steps.date.outputs.date }}
-
+      - name: Set profile file name env var
+        run: echo "LLVM_PROFILE_FILE=${{ github.workspace }}/grass-prof-%9m.profraw" >> $GITHUB_ENV
       - name: Environment info
         shell: bash -el {0}
         run: |
@@ -89,7 +100,10 @@ jobs:
         if: ${{ !cancelled() }}
         shell: micromamba-shell {0}
         run: source ./.github/workflows/print_versions.sh
-
+      - run: ls -la bin.*-*-*
+      - run: ls -la dist.*-*-*/bin
+      - run: ls -la "$HOME/install"
+      - run: ls -la "$HOME/install/bin"
       - name: Run pytest with multiple workers in parallel
         shell: micromamba-shell {0}
         run: |
@@ -104,8 +118,11 @@ jobs:
         run: |
           export PYTHONPATH=$(grass --config python_path):$PYTHONPATH
           export LD_LIBRARY_PATH=$(grass --config path)/lib:$LD_LIBRARY_PATH
+          export INITIAL_GISBASE="$(grass --config path)"
+          export INITIAL_PWD="${PWD}"
           pytest \
             @.github/workflows/pytest_args_ci.txt \
+            @.github/workflows/pytest_args_cov.txt \
             @.github/workflows/pytest_args_not_parallel.txt \
             -k 'not testsuite'
       - name: Run pytest with a single worker (for gunittest-based tests)
@@ -115,6 +132,85 @@ jobs:
           export LD_LIBRARY_PATH=$(grass --config path)/lib:$LD_LIBRARY_PATH
           pytest \
             @.github/workflows/pytest_args_gunittest.txt
+      - name: Fix non-standard installed script paths in coverage data
+        shell: micromamba-shell {0}
+        run: |
+          export PYTHONPATH=$(grass --config python_path):$PYTHONPATH
+          export LD_LIBRARY_PATH=$(grass --config path)/lib:$LD_LIBRARY_PATH
+          export INITIAL_GISBASE="$(grass --config path)"
+          export INITIAL_PWD="${PWD}"
+          python utils/coverage_mapper.py
+          coverage combine
+          coverage html
+          coverage json
+      - name: Merge and index profile data
+        shell: micromamba-shell {0}
+        run: llvm-profdata merge -sparse *.profraw -o merged.profdata
+      - name: Show merged profile data
+        shell: micromamba-shell {0}
+        continue-on-error: true
+        run: llvm-profdata show merged.profdata
+      - run: ls -la "$HOME/install"
+      - run: ls -la "$HOME/install/bin"
+      - name: Create a line-oriented coverage report
+        shell: micromamba-shell {0}
+        continue-on-error: true
+        run: |
+          llvm-cov show -use-color -instr-profile=merged.profdata \
+            /Users/runner/install/grass85/lib/libgrass_gis.8.5.dylib
+      - name: Create a line-oriented coverage report
+        shell: micromamba-shell {0}
+        continue-on-error: true
+        run: |
+          llvm-cov show -use-color -instr-profile=merged.profdata \
+            /Users/runner/install/grass85/lib/*.dylib
+      - name: Export coverage report with llvm-cov export
+        if: false
+        shell: micromamba-shell {0}
+        continue-on-error: true
+        run: llvm-cov export -format=text -instr-profile=merged.profdata /Users/runner/install/grass85/lib/libgrass_gis.8.5.dylib | tee coverage.libgrass_gis.json
+      - name: Export coverage report with llvm-cov export
+        if: false
+        shell: micromamba-shell {0}
+        continue-on-error: true
+        run: llvm-cov export -format=text -instr-profile=merged.profdata /Users/runner/install/grass85/lib/*.dylib | tee coverage.libs.json
+      - name: Export coverage report with llvm-cov export
+        shell: micromamba-shell {0}
+        continue-on-error: true
+        run: llvm-cov export -format=lcov -instr-profile=merged.profdata /Users/runner/install/grass85/lib/*.dylib | tee coverage.libs.lcov
+      - name: Make profile data available
+        if: ${{ !cancelled() }}
+        uses: actions/upload-artifact@0b2256b8c012f0828dc542b3febcab082c67f72b # v4.3.4
+        with:
+          name: >-
+            profile-data-${{ 'macos-14' }}
+          path: |
+            *.prof*
+            *coverage*
+          retention-days: 1
+      - run: /usr/bin/find . -type f \( -name "*.o" -or -name "*.prof*" \)
+      - run: /usr/bin/find . -type f \( -name "*.profraw" -or -name "*.profdata" \)
+      - run: /usr/bin/find $HOME/install -type f \( -name "*.o" -or -name "*.prof*" \)
+      - run: ls -la
+      - run: ls -la "$HOME/install"
+      - run: ls -la "$HOME/install/bin"
+      - run: ls -la -R "$HOME/install"
+      - run: ls -la -R .
+      - name: Make python-only code coverage test report available
+        if: ${{ !cancelled() }}
+        uses: actions/upload-artifact@0b2256b8c012f0828dc542b3febcab082c67f72b # v4.3.4
+        with:
+          name: >-
+            python-codecoverage-report-${{ 'macos-14' }}
+          path: coverage_html_report
+          retention-days: 1
+      - name: Upload coverage reports to Codecov
+        uses: codecov/codecov-action@ad3126e916f78f00edff4ed0317cf185271ccc2d # v5.4.2
+        with:
+          verbose: true
+          flags: pytest-macos-14
+          name: pytest-macos-14
+          token: ${{ secrets.CODECOV_TOKEN }}
 
       - name: Cache GRASS Sample Dataset
         id: cached-data
diff --git a/.github/workflows/macos_install.sh b/.github/workflows/macos_install.sh
index 4f340c73f9e..bcc95072368 100755
--- a/.github/workflows/macos_install.sh
+++ b/.github/workflows/macos_install.sh
@@ -59,11 +59,17 @@ CONFIGURE_FLAGS="\
   --without-x \
 "
 
+# export EXTRA_COV_FLAGS="-fprofile-instr-generate -fcoverage-mapping -mllvm -runtime-counter-relocation"
+export EXTRA_COV_FLAGS="-fprofile-instr-generate -fcoverage-mapping"
 export CFLAGS="-O2 -pipe -ffp-contract=off -arch ${CONDA_ARCH} -DGL_SILENCE_DEPRECATION -Wall -Wextra -Wpedantic -Wvla"
 export CXXFLAGS="-O2 -pipe -ffp-contract=off -stdlib=libc++ -arch ${CONDA_ARCH} -Wall -Wextra -Wpedantic"
 export CPPFLAGS="-isystem${CONDA_PREFIX}/include"
 
-./configure $CONFIGURE_FLAGS
+# export LDFLAGS="-v -fprofile-instr-generate -fcoverage-mapping"
+export CFLAGS="$EXTRA_COV_FLAGS $CFLAGS"
+export CXXFLAGS="$EXTRA_COV_FLAGS $CXXFLAGS"
+
+LDFLAGS="-v -fprofile-instr-generate -fcoverage-mapping $LDFLAGS" ./configure $CONFIGURE_FLAGS
 
 EXEMPT=""
 make -j$(sysctl -n hw.ncpu) CFLAGS="$CFLAGS -Werror $EXEMPT" \
diff --git a/.github/workflows/print_versions.sh b/.github/workflows/print_versions.sh
index 68b359c1b96..28cbd7d98ef 100755
--- a/.github/workflows/print_versions.sh
+++ b/.github/workflows/print_versions.sh
@@ -13,3 +13,5 @@ grass --version
 grass --tmp-project XY --exec g.version -ergb
 # Detailed Python version info (in one line thanks to echo)
 grass --tmp-project XY --exec bash -c "echo Python: \$(\$GRASS_PYTHON -c 'import sys; print(sys.version)')"
+
+grass --config
\ No newline at end of file