For topics related to XZ Utils, the address is xz at tukaani dot org. It forwards to Lasse Collin and Sam James.

For other topics, Lasse Collin’s address is lasse.collin at Sometimes I’m a bit slow to answer. If you don’t get a reply within two weeks, assume that the email has got lost and try either resending or use the other contact methods below.

As of May 2024, I’m more than two weeks late with many emails.

If needed, Lasse’s OpenPGP key fingerprint is 3690 C240 CE51 B467 0D30 AD1C 38EE 757D 6918 4620.

The XZ mailing lists are described on a separate page.


The Tukaani project’s IRC channel is #tukaani on Libera Chat. Nicks:

  • Larhzu: Lasse Collin

  • sam_: Sam James

Remember that people are from different timezones and not online every day. If you get no reply and cannot leave your IRC client online, try the other contact methods listed above.


The XZ projects repositories are on GitHub under the Tukaani organization. It’s one of the channels to report bugs or submit patches.

Reviewing open pull requests is encouraged. Constructive comments are welcome from anyone; one doesn’t need to be an existing contributor!