Yes, #slackware current includes #Landlock support in the testing group with #kernel 6.14.
However, you must enable it at boot. If you're using #GRUB, follow these steps:

1. Add the following line to /etc/default/grub:

GRUB_CMDLINE_LINUX_DEFAULT="lsm=landlock"

2. Regenerate the GRUB configuration:

geninitrd

3. Reboot your system and verify that Landlock is enabled:

sudo dmesg | grep landlock

Example output:

[ 0.000000] Command line: BOOT_IMAGE=/boot/vmlinuz-generic root=UUID=... ro lsm=landlock
[ 0.068388] Kernel command line: BOOT_IMAGE=/boot/vmlinuz-generic root=UUID=... ro lsm=landlock
[ 0.212270] LSM: initializing lsm=capability,landlock
[ 0.212270] landlock: Up and running.

Once enabled, you can use landrun on Slackware-current:
https://slackbuilds.org/repository/15.0/network/landrun/