Messaging Layer Security (MLS) is an IETF standard for end-to-end encryption in messaging systems. We are investigating bringing MLS to Matrix. So far we have basic encryption and decryption working and can handle membership changes.'

MLS IETF working group: https://datatracker.ietf.org/wg/mls/about/, and MLS is releaseed RFC9420.

MLS github group: https://github.com/mlswg .

Website about MLS:

• https://messaginglayersecurity.rocks/
• https://arewemlsyet.com/

• MLSpp (C++) https://github.com/cisco/mlspp  (Status: RFC)
• OpenMLS (Rust)https://github.com/openmls/openmls  https://openmls.tech/ (Status: RFC)
• mls-kotlin (Kotlin) https://github.com/Traderjoe95/mls-kotlin  (Status: RFC)
• mls-rs (Rust) https://github.com/awslabs/mls-rs  (Status: RFC)
• BouncyCastle (Java) https://github.com/bcgit/bc-java  (Status: RFC)

More implementations: https://github.com/mlswg/mls-implementations/blob/main/implementation_list.md