Dr.Livesey, In the case of end-to-end encryption on the openness / closeness of the server absolutely do not care.
The tdlib library is fully open and its sources are available. Compile and use as much as you want in your client.
Dr.Livesey @ 07.16.18, 12:14
Even if it were open, one and a half geeks who can and will want to compile themselves do not change anything globally,
“I’m too lazy / I don’t know how to compile a client, so it’s not safe.” : D
If you think that the code is not safe - indicate specific places in the code, if this is confirmed, you will even be paid money according to the error trapping program. And if you can't, then you just shake the air and mislead people.