Streamlining CI/CD with Modern CMake Presets

When comparing the new ci.yml and CMakePresets.json files against the older ci-prev.yml, one improvement stands out: complex command-line arguments have been replaced with reusable presets, dramatically simplifying and standardizing the CI pipeline. This shift leverages Modern CMake’s Presets feature, bringing clarity, consistency, and maintainability to the workflow.

I. Fundamental Improvements Through CMake Presets

In the legacy ci-prev.yml, every CMake variable—such as -DCMAKE_BUILD_TYPE or -DCMAKE_TOOLCHAIN_FILE—was defined manually inside the CI script. The new approach moves this complexity into CMakePresets.json, where reusable presets encapsulate all configuration details.

Centralized Build Settings & Reproducibility
Presets ensure every team member shares the same build environment, guaranteeing consistency and reproducibility. A hidden base preset (ci-base) defines common properties such as the Ninja generator, VCPKG toolchain path, and flags for building tests and examples. All other presets inherit from this base, reducing duplication.
Simplified CLI Usage
Instead of typing long, error-prone command lines, builds can now be invoked with a single command:
```
cmake --preset <name>
```

II. Job-Specific Enhancements in CI/CD

Job	Legacy (`ci-prev.yml`)	Improved (`ci.yml` + Presets)
Build Matrix	Hardcoded options like `cmake -B build -DCMAKE_BUILD_TYPE=$ ...`	Simplified to `cmake --preset $` and `cmake --build --preset $`, with build type and binary directory automatically resolved.
Code Coverage	Coverage flags manually injected into `CMAKE_CXX_FLAGS`.	A dedicated `coverage` preset encapsulates flags and sets `Debug` mode. Examples are disabled to optimize build and reporting time.
Static Analysis	Manual invocation of `cmake -B build -DCMAKE_EXPORT_COMPILE_COMMANDS=ON`.	An `analysis` preset defines `CMAKE_EXPORT_COMPILE_COMMANDS: ON` and disables tests/examples, speeding up `compile_commands.json` generation.

III. Clearer Test Execution Environment

Previously, tests required explicit working-directory settings and manual ctest calls. The new workflow uses:

ctest --preset $

This leverages testPresets in CMakePresets.json:

Linking Build & Test Configurations
Each test preset references its corresponding configure preset (e.g., "configurePreset": "debug"), ensuring CMake knows exactly which binaries to test.
Standardized Output
With "outputOnFailure": true, detailed logs appear only when tests fail, keeping CI logs concise and readable.

IV. Coverage Implementation Best Practices

The updated pipeline also integrates industry-standard practices for coverage:

Dedicated Coverage Job
Coverage builds are separated from release builds, using Debug mode to ensure accurate instrumentation.
Compiler Flags Encapsulated in Presets
Coverage flags (--coverage -fprofile-arcs -ftest-coverage) are defined inside the coverage preset, not hardcoded in CI scripts.
Accurate Reporting with lcov
- lcov --capture consolidates .gcda and .gcno files into a single report.
- lcov --remove excludes system headers and external libraries, focusing coverage on project code.
Codecov Integration
The pipeline uses codecov/codecov-action@v4 to upload results, simplifying authentication and report publishing.

Conclusion

By adopting Modern CMake Presets, the SensorStreamKit CI/CD pipeline has evolved into a cleaner, more maintainable system. Presets centralize build settings, eliminate redundant command-line arguments, and ensure reproducibility across environments. Combined with best practices for coverage and analysis, this workflow exemplifies how modern tooling can transform CI/CD pipelines into efficient, reliable processes.

Would you like me to also shape this into a step-by-step tutorial style (with code snippets and “how to apply this in your own project” sections), or keep it as a case study narrative? Both could work well depending on your target audience.

References

CMake –preset: 더 이상 길고 복잡한 빌드 명령어에 시달리지 말자: https://craftsmanship.tistory.com/m/125
Building with CMake Presets: https://mcuoneclipse.com/2023/12/03/building-with-cmake-presets/