Negotiate for larger MTU

[reallyroy]

Hi,

I'm in the process of porting some BLE peripheral code based on Bleno to GO. I am using this gatt package for the same. But I have hit an issue that I'm unsure how to solve. In the bleno based peripheral, I was able to write large data to a characteristic. When I say large I mean a base64 string of around 350 characters. However, when I run the same test on this package, the write doesn't happen if the string is greater than the MTU of the Central. Perhaps, the bleno code negotiates for a larger MTU? Or chunks internally?

How do I get the peripheral to negotiate for a larger MTU size?

Regards,
Roy