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+# Changes to the microsoft/surface top-level
+
+## Overview
+
+When I (@mexisme) created the microsoft/surface profile, there weren't that many differences between
+the various models of Surface.
+
+I had just acquired a Surface Go 1, and it was mostly safe to enable all the options for all the
+models, and they would fail gracefully enough that we could mostly ignore warnings or errors.
+
+Now, however --- as-of 2023-01-10 --- we have a much wider variety of chipsets, incl. models with
+some of the newer AMD CPUs, and this is breaking small things in annoying ways for more people.
+
+## Changes
+
+### Model Specialisations
+
+In keeping with the broader structure of "nixos-hardware", I've also changed the structure of the
+microsoft/surface profile to make it easier for people to specialise for their hardware.
+
+Any code or modules that are specialised for a Surface model now have their own directory under this
+top-level.
+
+E.g. I am moving the Surface Go specialisations into `surface-go/`, and there may be further
+specialisations like `surface-go-3/`.
+
+### "Common" modules
+
+All the "common" modules that were once in the top-level of the microsoft/surface profile have moved
+under the `common/` directory.
+
+Tools / services that are shared among several models are now extracted to their own module under
+`common/` and imported by `common/default.nix`.
+These new "common" modules now have an `enable` option, which is `false` by default.
+
+### "Old Behaviour" module
+
+The original `./default.nix` module has been replaced by a new `old/` module, which replicates the
+original behaviour.
+
+The new `./default.nix` will load the new `old/` module, but will also pop-up a warning asking users
+to update how they use the microsoft/surface profile from now on.
+This warning will probably change to a fail assertion at some point in the future.
+
+## Adding a new Model Specialisation
+
+This hasn't been finalised, partly as I now only have access to a Surface Go 1, these days, so I'm
+maybe not the best custodian of this code any longer.
+
+However, hopefully the (imminent) `surface-go/` module is a reasonable exmample, and we should be
+able to gather more examples for more model specialisations over time.