You will need the following:
1x Mechanix Base OR for a Guard Mechanix, Mechanix Base: Guard
Available via Crafting!
1x Mechanix Pelt
Availablle via Crafting!
1x Mechanix Chip
Available via Crafting, Breeding Mechanix, or Scientific Analysis! Of all these, Crafting has the most limited stock of chip types, and Breeding can get you almost anything, but may be a bit unpredictable.
Alternately: You can use 1x Holo Hacker Companion or Holo Helper Companion in place of a chip if you have one! This effectively 'uploads' the companion into the import. This is the only way to have a Holo Hacker/Helper chip in a Mechanix.
Submit these as Items Used in Design Approvals with your Mechanix import, and you'll have built your robot friend!
Mechanix can only breed with other Mechanix - it's technically not 'breeding' so much as 'combining data'. Some Mechanix do see this as intimate - it's done by clasping paws together and hooking up ports that send and receive information, so not only do the pair have to trust each other, they have to be physically close. Once the combination of data is complete, the new Mechanix program can be output into chips. (2-4 can be made from each data combination.)
This can often result in different outcomes than what most crafters can make...
But also, very importantly, since 'breeding' with Mechanix results in a lineage-free chip, Mechanix cannot inbreed!
Do Mechanix eat food to get stats?
Yes, I didn't feel like disallowing this. I'll probably be introducing comically strange robot food much like we have Chasm food.
Do Mechanix have radiation? Elements?
This was originally going to be a no, but again... I didn't feel like disallowing this. V: Lore-wise, they're not using rads (usually) (they CAN). Gameplay-wise, they CAN, so why restrict it.
Are there item restrictions?
Mechanix can't use geno-editing items because like
what geno
Otherwise, most things work similarly. Mutation Stations can add modifications, Scarification Kits can gouge the pelt and metal body, Cosmetics aren't as necessary due to the nature of 100% customization but can be handy if you don't want to do a full redesign and just want to do a little stripe or two. Custom accessories and apparel and such is still A-OK.
As Mechanix don't have mutations, most of these can be added with Mutation Stations, including things like smoke effects (like incense) and halos (like... halos) - these do not have to be limited to auras behind the Mechanix done with a Wax Paper Background Canvas and if done with a Mutation Station can be attached to or in front of the Mechanix's body. Bioluminescence does not require an item.
The only things of note that have nothing to do with geno editing are:
What is the Pelt made of and why is it creepy?
The mechanix pelt is most likely made of synthetic material. In the rare cases that it's made of real fur (very rare unless you have a crafter who's super dedicated to taxidermy), it's probably sourced from Sxriix'n wildcat or ursine, and treated to last as long as possible. There are magnetic pieces on the inside of the pelt that hold it in place on the base. It's a robot fursuit. A very short Domestic could probably wear it if they didn't mind the magnetic nubs poking them.
The "head" on the image was referenced from taxidermy which looks super weird popped onto a folded hoodie shape, it was 100% intentionally unsettling! Sorry! =D
Can I swap my uploaded Mechanix's build to another type?
Yes! Just use the intended build's base (The Mechanix Base for classic and Mechanix Base: Guard for guard for instance) as your editing item, and submit at redesigns as per usual! Your design should stay mostly the same unless you're using a pelt as well to update your design!