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+# Guidance for porting to new platform
+
+Where differences existed between the initial POSIX platform for lws and other
+supported platforms like Windows, `lws_plat_...()` apis were added to move
+handling to platform-specific code in `./lib/plat/`.
+
+Depending o which platform is built, different platform-specific implementations
+of these `lws_plat...()` apis get built.
+
+## 1) Prepare the cmake cross-build file if necessary
+
+CMake isolates its settings for cross-build into a separate file, which can be
+used to different cmake projects for the same platform as well.
+
+Find a similar examples already in `./contrib/cross-*` and copy and adapt it
+as needed,
+
+All settings related to toolchain should go in there.  For cross-toolchain,
+the convention is to pass the path to its installed directory in `CROSS_PATH`
+environment variable.
+
+## 2) Copy the closest platform dir in ./lib/plat
+
+Wholesale copy the closest existing platform dir to `/lib/plat/myplatform` and
+rename the files.
+
+Remove stuff specific to the original platform.
+
+## 3) Add a flag in CMakeLists.txt
+
+Cut and paste a flag to select your platform, preferably `LWS_PLAT_MYPLATFORM` or so
+
+## 4) Add a section to force-select and deselect other cmake options based on platform flag
+
+Some options on by default may not make sense on your platform, and others off
+by default may be mandatory.  After the options() section in CMakeLists.txt, you
+can use this kind of structure
+
+```
+	if (LWS_PLAT_MYPLATFORM)
+		set(LWS_WITH_XXXX 0)
+	endif()
+```
+
+to enforce implicit requirements of your platform.  Optional stuff should be set by
+running cmake commandline as usual.
+
+## 5) Add building your platform files into CMakeLists.txt
+
+Add entries in CMakeLists.txt for building stuff in `./lib/plat/myplatform` when
+`LWS_PLAT_MYPLATFORM` is enabled.
+
+## 6) Adapt your copied ./lib/plat/myplatform/ files
+
+You can now do test builds using the cross-build file, your platform flag in
+cmake, and your copied ./lib/plat content... this last part since it was
+copied from another platform will initially be a plentiful source of errors.
+
+You can iteratively build and adapt the platform files.
+