Derp Slider

The Derp Slider is the pack's answer to a surprisingly common want: a real slider, not a number box, for the float values you keep tweaking - CFG scale, denoise, LoRA strength, sampler-ish knobs you drag rather than type. It's a configurable float/int slider whose output is broadcast wirelessly instead of being dragged across the canvas on a wire. Part of xcp_derp-UI (search "xcp_derp-UI" in ComfyUI Manager, by lordwedggie), under derpNodes/ControlDeck.

Why you'd want it

The KB's comfyui-node-plumbing.md makes the case that the plumbing layer of ComfyUI exists to fight repetition and illegibility - one value feeding five places, without five wires. The Derp Slider is that idea with a handle on it: set a slider once, and every receiver on the canvas gets the same value through the wireless registry, no spaghetti. If you've got three different nodes that all want the same denoise strength, this is one drag instead of three typed numbers.

How it works

The node is a pure virtual shell - the Python do_nothing returns None from its single value output (type FLOAT), and the real value lives in the pack's wireless signal registry. The slider is configurable through its UI: min, max, step, default, and decimals. The core slider logic clamps your input to [min, max], snaps to the step when snapping is on (round(raw / step) * step), and rounds to your decimal setting before broadcasting. So you can build a fine-grained 0–1 slider with 2 decimals for CFG, or a coarser 0–100 integer-ish slider for batch counts - same node, different config.

Because the output is wireless, receivers are the pack's other derp nodes or default ComfyUI nodes wearing a derp Wireless Extender - and as always in this pack, a derpRouter is what routes the signal. No Router, no signal, no value at the other end.

Install

cd ComfyUI/custom_nodes
git clone https://github.com/lordwedggie/xcp_derp-UI-Release

Restart ComfyUI. No pip requirements, no model downloads, no npm step - the pack vendors its JS. Manager users: search xcp_derp-UI.

Where people get burned

The pattern you'll see with every pure-virtual derp node: wire the value output into a stock ComfyUI node and expect the classic behavior - it won't work that way, because the value arrives via signal, not via that wire. The mental model to internalize: this pack's nodes talk to each other through the Router, and they talk to default nodes only if you attach a Wireless Extender to the default node via its right-click menu.

Second, snap surprises: if your slider is stepping through values you didn't expect, check the step - snapping to 0.05 on a 0–1 range gives you the classic "why won't it hit exactly 0.7" moment. Set decimals and step to match what you're tuning. And third, this is a young pack with thin third-party coverage; the bundled derp_docs/ docs and the changelog are the reference, and for a node this simple they're plenty.