Why isn’t Telegram server code open source?
Pavel DurovLast update: January 30, 2021
Edited by fpoi.org
FAQ: Can I get Telegram's server-side code?
All Telegram client apps are fully open source. We offer verifiable builds both for iOS and Android – this technology allows to independently verify that the application you download from the app stores was built using the exact same code that we publish.
By contrast, publishing the server code doesn’t provide security guarantees neither for Secret Chats nor for Cloud Chats. This is because – unlike with the client-side code – there’s no way to verify that the same code is run on the servers.
As for Secret Chats, you don’t need the server-side code to check their integrity – the point of end-to-end encryption is that it must be solid regardless of how the servers function.
In a post on his channel, Pavel Durov explained why Telegram hasn't published the server code, even as a publicity stunt.
The encryption and API used on Telegram's servers are fully documented and open for review by security experts. We welcome any comments at security@telegram.org
FAQ: Can I run Telegram using my own server?
Our architecture does not support federation yet. Telegram is a unified cloud service, so creating forks where two users might end up on two different Telegram clouds is unacceptable. To enable you to run your own Telegram server while retaining both speed and security is a task in itself. At the moment, we are undecided on whether or not Telegram should go in this direction.