Back to the first days of the general release of Apple Watch, I used some tools to reverse-engineer the frameworks (both Public and Private) from the first version of watchOS (called Watch OS back then). They actually came from a pre-release build of Watch OS (12S506) that wasn’t a public build, but left on the Apple servers dedicated to OTA updates.
The headers are available on GitHub: https://github.com/PierreBlazquez/Watch-OS-1.0-Frameworks-Headers
Public and Private Frameworks Headers, dumped from the dyld shared cache of Watch OS 1.0 (12S506) extracted from an OTA update v3 payload.
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