Where can I find information on developing widgets os x?

Tell me - where can I find information for developing widgets in notification center under os x? Everywhere on the Internet met only dashboard widgets. But this is after all other widgets, I suspect that the process of developing them is different.
September 19th 19 at 12:35
1 answer
September 19th 19 at 12:37
Thank you - soledad.Bailey71 commented on September 19th 19 at 12:40

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