Simdim is a distributed, friend-to-friend instant messenger. It works without a central server and can even work in an isolated local area network, providing synchronized friend-to-friend chat and synchronized group chat with access levels.

It does its best to encrypt and sign everything to guarantee confidentiality, integrity and authenticity. At the moment anonymity is not in scope. By nature everything is end-to-end encrypted, and persons are identified using their public keys, which removes limitations and security concerns linked with using a phone number or an email address, albeit decreasing usability a little.

It is very alpha at the moment, there are not many features, expect bugs and rough edges. I have lots of ideas to improve usability though.

Simdim is free software released under the terms of the GNU General Public Licence v3.


If you find my work useful and want to help me, I accept donations on the following platforms and cryptocurrencies:

Thank you very much!


I had created Debian packages and repositories but it appeared that they weren’t working great. I will fix that for the rc2.


Here is an installer that should work with Windows Vista and later:

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