Motorway 3x0

Motorway 3x0 is the write-only node with three bays. The name is Motorway [inputs]x[outputs], so this is three values in and zero data outputs - it swallows three things, tags each with a key, and passes the bus onward without surfacing anything itself. It's the node for the workflow where you want to record three values now and read them much later, on a completely different part of the graph, without dragging three wires across the whole canvas.

It comes from agilly1989/ComfyUI_agilly1989_motorway, a beta "pipe" pack by solo dev agilly1989. Same idea as rgthree's Context nodes and Impact Pack pipes - one wire carries a bundle of values - but the transport is a MotorwayClass bus object instead of a dict. The bus connection is MOTORWAY 🚌💨, required on every node and always the first output so the route continues. You start at MotorwayStart; the Motorway primitive nodes (seed, int, float, string) can also start a fresh bus.

How it works

The pack's rule: each data input gets a _key box, and the value is stored under whatever name you type. Here that's three pairs:

• inputs ANY_(A), ANY_(B), ANY_(C) with keys ANY_(A)_key, ANY_(B)_key, ANY_(C)_key
• the required MOTORWAY 🚌💨 bus input
• a single output: the continued MOTORWAY 🚌💨 bus

Because there are no data outputs, 3x0 is a pure sink. Park cfg, steps and denoise here; later, any Motorway node with a read slot - a 1x3, a 3x3, a 2x10 - can pull them back by key. That's the pattern the pack's Example.json demonstrates: write-only nodes stash state early, read-capable nodes surface it where it's needed.

Keys aren't stored under their literal names. The pack sha256-hashes each one into an attribute like hash_9c2a…, which is why a missing key produces 'MotorwayClass' object has no attribute 'hash_' instead of a clear message. And the bus is not a log: writing the same key again, anywhere on the route, overwrites the earlier value.

Installing

cd ComfyUI/custom_nodes
git clone https://github.com/agilly1989/ComfyUI_agilly1989_motorway

then restart ComfyUI, or search ComfyUI_agilly1989_motorway in ComfyUI Manager. No pip dependencies, no model downloads - pure Python, so clone-and-restart is everything.

Common issues

• The hash_ error means you referenced a key that was never written - check the exact string, including case and spaces, on the node that should have stored it.
• Type a key but leave the input disconnected and the node stores None under that name, silently erasing anything there. Only key inputs you've wired up.
• New users often hunt for an output that doesn't exist. There is none. That's the point - read it back downstream instead.

Beta pack, author's disclaimer included. For tucking three values onto the route for later, 3x0 is the cleanest way to do it.