It’s in the current experimental, you need to craft a fishing hook from a nail and a fishing rod.
The fishing rod recipe is literally, a stick, some string and a fishing hook. 
{
"type":"TOOL",
"id": "fishing_rod_basic",
"symbol": "/",
"color": "brown",
"name": "basic fishing rod",
"description": "'Fishing rod' might be a bit too charitable of a description. In truth, this is a stick with a piece of string and a hook.",
"price": 0,
"material": "wood",
"weight": 1700,
"volume": 5,
"bashing": 14,
"cutting": 0,
"max_charges": 0,
"initial_charges": 0,
"charges_per_use": 0,
"turns_per_charge": 0,
"ammo": "NULL",
"flags": ["FISH_POOR"],
"use_action": "FISHING_BASIC",
"revert_to": "null",
"to_hit": 1
},
This is the only rod in game at the moment and the recipe fabrication skill lists survival.
Don’t worry though I’m sure we’ll be getting intermediate and sports-grade rods sooner or later so we can go all ROBSON GREENE, EXTREME.
Also do we have bait yet? if not I’ll code in some kind of chum or bait.
[edit] Also holy crap, wito is a goddamn hero. There are loads of different types of fish to catch.