* Merged the |UNITTESTING| "building" stage with "uploading" for the embedded target (`issue #4307 <https://github.com/platformio/platformio-core/issues/4307>`_)
* Fixed an issue when a custom `pio test --project-config <https://docs.platformio.org/en/latest/core/userguide/cmd_test.html#cmdoption-pio-test-c>`__ was not handled properly (`issue #4299 <https://github.com/platformio/platformio-core/issues/4299>`_)
* Control |UNITTESTING| verbosity with a new multilevel `pio test -v <https://docs.platformio.org/en/latest/core/userguide/cmd_test.html#cmdoption-pio-test-v>`__ command option (`issue #4276 <https://github.com/platformio/platformio-core/issues/4276>`_)
* Fixed an issue when the `build_src_flags <https://docs.platformio.org/en/latest/projectconf/section_env_build.html#build-src-flags>`__ option was applied outside the project scope (`issue #4277 <https://github.com/platformio/platformio-core/issues/4277>`_)
* Fixed an issue when calling the built-in `pio device monitor <https://docs.platformio.org/en/latest/core/userguide/device/cmd_monitor.html#filters>`__ filters
* Added support for `"scripts" <https://docs.platformio.org/en/latest/librarymanager/config.html#scripts>`__ (`issue #485 <https://github.com/platformio/platformio-core/issues/485>`_)
* Added support for `multi-licensed <https://docs.platformio.org/en/latest/librarymanager/config.html#license>`__ packages using SPDX Expressions (`issue #4037 <https://github.com/platformio/platformio-core/issues/4037>`_)
* Added support for `"dependencies" <https://docs.platformio.org/en/latest/librarymanager/config.html#dependencies>`__ declared in a "tool" package manifest
- Added support for `symbolic links <https://docs.platformio.org/en/latest/core/userguide/pkg/cmd_install.html#local-folder>`__ allowing pointing the local source folder to the Package Manager (`issue #3348 <https://github.com/platformio/platformio-core/issues/3348>`_)
- Automatically install dependencies of the local (private) project libraries (`issue #2910 <https://github.com/platformio/platformio-core/issues/2910>`_)
- Ignore files according to the patterns declared in ".gitignore" when using the `pio package pack <https://docs.platformio.org/en/latest/core/userguide/pkg/cmd_pack.html>`__ command (`issue #4188 <https://github.com/platformio/platformio-core/issues/4188>`_)
- Dropped support for the "pythonPackages" field in "platform.json" manifest in favor of `Extra Python Dependencies <https://docs.platformio.org/en/latest/scripting/examples/extra_python_packages.html>`__
- Fixed an issue when manually removed dependencies from the |PIOCONF| were not uninstalled from the storage (`issue #3076 <https://github.com/platformio/platformio-core/issues/3076>`_)
- New: Hardware `Simulators <https://docs.platformio.org/en/latest/advanced/unit-testing/simulators/index.html>`__ for Unit Testing (QEMU, Renode, SimAVR, and custom solutions)
- Added support for a `custom testing framework <https://docs.platformio.org/en/latest/advanced/unit-testing/frameworks/custom/index.html>`_
- Added support for a custom `testing command <https://docs.platformio.org/en/latest/projectconf/section_env_test.html#test-testing-command>`__
- Added support for a `custom Unity library <https://docs.platformio.org/en/latest/advanced/unit-testing/frameworks/custom/examples/custom_unity_library.html>`__ (`issue #3980 <https://github.com/platformio/platformio-core/issues/3980>`_)
- Added support for the ``socket://`` and ``rfc2217://`` protocols using `test_port <https://docs.platformio.org/en/latest/projectconf/section_env_test.html#test-port>`__ option (`issue #4229 <https://github.com/platformio/platformio-core/issues/4229>`_)
- List available project tests with a new `pio test --list-tests <https://docs.platformio.org/en/latest/core/userguide/cmd_test.html#cmdoption-pio-test-list-tests>`__ option
- Pass extra arguments to the testing program with a new `pio test --program-arg <https://docs.platformio.org/en/latest/core/userguide/cmd_test.html#cmdoption-pio-test-a>`__ option (`issue #3132 <https://github.com/platformio/platformio-core/issues/3132>`_)
- Generate reports in JUnit and JSON formats using the `pio test <https://docs.platformio.org/en/latest/core/userguide/cmd_test.html>`__ command (`issue #2891 <https://github.com/platformio/platformio-core/issues/2891>`_)
- Provide more information when the native program crashed on a host (errored with a non-zero return code) (`issue #3429 <https://github.com/platformio/platformio-core/issues/3429>`_)
- Fixed an issue when command line parameters (``--ignore``, ``--filter``) do not override values defined in the |PIOCONF| (`issue #3845 <https://github.com/platformio/platformio-core/issues/3845>`_)
- Renamed the "test_build_project_src" project configuration option to the `test_build_src <https://docs.platformio.org/en/latest//projectconf/section_env_test.html#test-build-src>`__
- Removed the "test_transport" option in favor of the `Custom "unity_config.h" <https://docs.platformio.org/en/latest/advanced/unit-testing/frameworks/unity.html>`_
- Added support for the custom `Clang-Tidy <https://docs.platformio.org/en/latest/plus/check-tools/clang-tidy.html>`__ configuration file (`issue #4186 <https://github.com/platformio/platformio-core/issues/4186>`_)
- Added ability to override a tool version using the `platform_packages <https://docs.platformio.org/en/latest/projectconf/section_env_platform.html#platform-packages>`__ option (`issue #3798 <https://github.com/platformio/platformio-core/issues/3798>`_)
- Fixed an issue with improper handling of defects that don't specify a source file (`issue #4237 <https://github.com/platformio/platformio-core/issues/4237>`_)
- Fixed an issue when |LDF| ignores the project `lib_deps <https://docs.platformio.org/en/latest/projectconf/section_env_library.html#lib-deps>`__ while resolving library dependencies (`issue #3598 <https://github.com/platformio/platformio-core/issues/3598>`_)
- Fixed an issue when GCC preprocessor was applied to the ".s" assembly files on case-sensitive OS such as Window OS (`issue #3917 <https://github.com/platformio/platformio-core/issues/3917>`_)
- Fixed an issue when |LDF| ignores `build_src_flags <https://docs.platformio.org/en/latest/projectconf/section_env_build.html#build-src-flags>`__ in the "deep+" mode (`issue #4253 <https://github.com/platformio/platformio-core/issues/4253>`_)
- Added a new build variable (``COMPILATIONDB_INCLUDE_TOOLCHAIN``) to include toolchain paths in the compilation database (`issue #3735 <https://github.com/platformio/platformio-core/issues/3735>`_)
- Changed a default path for compilation database `compile_commands.json <https://docs.platformio.org/en/latest/integration/compile_commands.html>`__ to the project root
- Renamed the "src_build_flags" project configuration option to the `build_src_flags <https://docs.platformio.org/en/latest/projectconf/section_env_build.html#build-src-flags>`__
- Renamed the "src_filter" project configuration option to the `build_src_filter <https://docs.platformio.org/en/latest/projectconf/section_env_build.html#build-src-filter>`__
- Pass extra arguments to the `native <https://docs.platformio.org/en/latest/platforms/native.html>`__ program with a new `pio run --program-arg <https://docs.platformio.org/en/latest/core/userguide/cmd_run.html#cmdoption-pio-run-a>`__ option (`issue #4246 <https://github.com/platformio/platformio-core/issues/4246>`_)
