This is not open sourcing any actual software or hardware it is “open-sourcing the API documentation for its SoundTouch smart speakers”. You might be able to point them at an alternative back-end¹ if you want the cloud features, but that will need to be written from scratch rather than being forked from code provided by Sonos.
> When cloud support ends, an update to the SoundTouch app will add local controls to retain as much functionality as possible without cloud services
This is a far bigger move than releasing API information, IMO bigger than if they had actually open sourced the software & hardware, from the point of view of most end users - they can keep using the local features without needing anyone else to maintain a version.
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[1] TFA doesn't state that this will be possible, but opening the API makes no sense if it isn't.
> When cloud support ends, an update to the SoundTouch app will add local controls to retain as much functionality as possible without cloud services
This is a far bigger move than releasing API information, IMO bigger than if they had actually open sourced the software & hardware, from the point of view of most end users - they can keep using the local features without needing anyone else to maintain a version.
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[1] TFA doesn't state that this will be possible, but opening the API makes no sense if it isn't.