Fuji is a LockHTML theme which brings the macOS login screen to iOS. It's developed by the Swedish developer, Emil Avara. Fuji has existed for quite some time now, however, it just got one of the many updates which bring improvements and bugfixes. It features a tonne of customisation options which allow you to tweak it to your deepest desires.
Fuji doesn't look identical to the macOS login screen, as it's more of a merge between iOS and macOS. Though, you can change the settings and adjust it to get the true macOS look and feel if you so wish as the tweak offers a lot of different options to chose from.
The design is really sleek, with a minimalistic yet functional look. It gives your device a personality as it displays your profile picture right in the middle of the lockscreen, which gives you the "logging in onto an account" vibe. The only gripe with the profile picture system is that you need to upload it to some web image hosting service, like Imgur, as you can't use local pictures. That's a shame, but this could be resolved in a future update.
Fuji requires LockHTML to work, which is unfortunately not free. This means you'd have to pay for two tweaks if you haven't purchased any of these before.
Just as LockHTML, Fuji is compatible with all LockHTML versions, however, compatibility of devices like the iPad has not been tested so there is no guarantee it will work as expected. Generally, if you own multiple devices which are jailbroken, buying both Fuji and LockHTML may well be worth the price.
Fuji can be found on ZodTTD, going for $1.29 and LockHTML can be found by going to LockHTML's repo (first button) and installing the latest beta from there.