Editing layout of subways/sewers?

There’s probably an obvious answer to this but I’ve searched the files up and down and I can’t for the life of me find where the JSON for either of these are located. I was expecting it to be under mapgen with everything else but apparently not, unless I totally overlooked it. Is it even possible at this point in time?

They’re hardcoded at the moment.

Ah, well thanks anyway.

You can edit them, you cant view the hardcorded one though. But, if you make a json with the id of ‘sewers’ ala this, you can overwrite the defaults. idk if you can have both the default and your own intermixed via a weigh system though. havent tested that.

So if you really want to, you can make sewer models and have them spawn, but the effects might be less predictable.