PatchBay

Connecting things to things, the way a studio patches its gear: sockets down one side for what you have, sockets down the other for where it goes, and a cable between each connected pair. For mapping an import's columns to fields, routing events to channels, inputs to outputs. Each source has a Select that says where it goes, and that's the real control; the cables draw what the Selects say, and with a pointer you can drag one from socket to socket.

Feel Plugging cables into a patch panel: they drop into place and sway once.

E-mail

Full name

Company

Phone no.

Or let the agent fetch it: get_component("patch-bay") on the Echo MCP server.

Installation

npx echo-ui-cli add patch-bay

First time? Run npx echo-ui-cli init once — it sets the project up, and add refuses to run before it.

At a glance

Version: 0.3.0
Weight: 2.7 KB · 76.6 KB with what it imports · 2.0 KB of CSS (minified and gzipped; React not counted)
Needs: select (Echo, brought with it), status-dot (Echo, brought with it)
Keyboard: Tab reaches each source's Select, which opens with Enter, Space or the arrow keys and chooses with Enter, like any Select.
Reduced motion: Cables appear hanging at rest, without dropping or swaying.
Sound: The select click when a cable connects, and a tap when one comes out, inside a SoundProvider.

Usage

tsx

import { PatchBay } from "@/echo/patch-bay";

<PatchBay label="Import columns" sources={[{ value: "e-mail", label: "E-mail" }]} targets={[{ value: "email", label: "Email" }]} />

Composition

PatchBay
  the sources: a name, a Select (where it goes) and a socket per row
  the targets: a socket and a name per row
  the cables

Examples

Map an import

The file's columns on the left, your fields on the right.

tsx

<PatchBay
  label="Import columns"
  sourcesLabel="In your file"
  targetsLabel="Fields"
  sources={[{ value: "e-mail", label: "E-mail" }, { value: "name", label: "Full name" }]}
  targets={[{ value: "email", label: "Email" }, { value: "first", label: "First name" }]}
  defaultValue={{ "e-mail": "email" }}
/>

Controlled

The mapping in your state.

tsx

<PatchBay label="Routing" sources={events} targets={channels} value={routes} onValueChange={setRoutes} />

Accessibility

A group named by label. Each source has a Select named "<source> goes to", which is the whole control: keys, screen readers and forms use it.
The target column and the cables are a picture of what the Selects say, hidden from assistive technology.
Dragging a cable is a pointer extra; on a narrow screen the cables go and the Selects stay.
name submits each connection as name[source] with a form.
Keyboard: Tab reaches each source's Select, which opens with Enter, Space or the arrow keys and chooses with Enter, like any Select.

Tested against WCAG 2.2 AA on every release:

axe — No axe violations, in the component's own gallery and on its page.
keyboard — Every action is reachable and operable from the keyboard alone.
focus-visible — Focus is visible on every focusable part, in normal and forced-colors mode.
forced-colors — State stays visible when the look's colours are replaced by the system's.
target-size — Every target's real hit area is at least 24×24px, at every density.
reflow — Content reflows into 320px and survives a doubled text size.

Not covered: screen-reader: not yet verified by a person. Everything above is a machine check; a person has not yet driven this component with a screen reader.

Motion & sound

Motion tokens: springs
Reduced motion: Cables appear hanging at rest, without dropping or swaying.
Sound: The select click when a cable connects, and a tap when one comes out, inside a SoundProvider.

Props

PatchBay props
Prop	Type	Default
`id`The element's id, so a <label for> or an aria-describedby can reach it.	`string`
`name`The field's name in a form submission, and the key react-hook-form registers.	`string`
`disabled`	`boolean`	`false`
`required`	`boolean`
`readOnly`	`boolean`
`autoFocus`Focus this control when it mounts. One per page, at most.	`boolean`
`onBlur`Fired on focus loss. react-hook-form validates onTouched and onBlur with it.	`function`
`onFocus`Fired when the control takes focus.	`function`
`onKeyDown`Keyboard handling you own — Enter to send, Escape to clear. Runs before Echo's.	`function`
`label` requiredWhat's being connected: the group's accessible name ("Import columns").	`string`
`sources` requiredWhat you have: the left column.	`object[]`
`targets` requiredWhere it can go: the right column.	`object[]`
`sourcesLabel`The heading over the sources.	`string`	`"From"`
`targetsLabel`The heading over the targets.	`string`	`"To"`
`value`Where each source goes: its target's value, or null for nowhere (controlled).	`Record<string, unknown>`
`defaultValue`	`Record<string, unknown>`
`onValueChange`Called with where every source goes.	`function`

Anti-patterns

Never use a PatchBay for a list with one obvious answer each: a column of Selects is plainer.
Never make the cables the only way to connect: they draw the Selects; the Selects are the control.

Changelog

v0.3.0 · 2026-10-12 · AddedThe drawn device (echo-ui-core, echo-ui-cli, every component that draws its own material). A seed's new render setting is molded (Echo as it has always been: plastic lit by one key light) or drawn: the same parts drawn in the ink, the way a spec sheet draws a key. Every part is outlined at one weight (--echo-line, --echo-line-width), hollow on the body; a raised part stands on a hard ink edge as deep as it rises and travels down it when pressed; a recess is an outline drawn inside; something floating stands on a deeper edge. There's no light, so no gloss, no soft shadow and no glow: what a molded device lights (an LED, the rail, a readout, the focus ring, a fader's knob, a radio's pip) is solid ink, and a low-emphasis action is its label underlined. In black and white (the accent the ink) "on" is solid ink and what's drawn on it inverts: a switch's thumb turns paper, a fader's knob is knocked out with a paper ring. The primary key is the paper key that stands highest, on an ink edge twice as deep as a neutral one's, the way a spec sheet draws its CTA. The accent stays the seed's own colour as a flat fill for what's on (a chosen segment, a checked box, a slider's travel, a switch that's on), so an acid highlighter is acid, not the olive a molded device holds it to; what's drawn on it is the ink, or the body when the accent is too deep for the ink. Pressing, travel, sound, what each material is for and every contrast guarantee are unchanged. npx echo-ui-cli style set render drawn turns it on; a style sets it in its seed; the published style and config schemas describe it, and DESIGN.md says how a drawn device builds. A molded device renders exactly as before: every line is 0px wide there, and each drawn value a component reads (--echo-drawn-fill, -on-fill, -ink, -rule, -glass, -hollow, -decoration) is initial, so it falls back to what the component always drew. HardwareButton's bed is the one new hand-tuned shadow: a drawn key stands on its own edge instead of being drawn in a recess.
v0.3.0 · 2026-10-12 · ChangedEvery item needs echo-ui-core 0.3.0 (all components). The drawn device, readability past AA and the design tests live in core, and the components that use them are built against it, so each item now declares echo-ui-core >=0.3.0 <0.4.0. Update core with the items: npm install echo-ui-core@^0.3.0 (or your package manager's), then npx echo-ui-cli update. An item whose files didn't change is the same code under a new version; the 0.2.0 files stay published.
v0.2.0 · 2026-10-04 · AddedThe light device (echo-ui-core, echo-ui-cli). Echo can be light: a pale chassis makes a device molded in light plastic, like a white calculator or a cream radio, and a dark one makes the device Echo has always been. There's no setting and no mode to switch; the chassis decides (devicePolarity, and values.polarity on the theme). On a light device the page is light: its ground, the well, is the body barely set in. Caps get their own ladder, a step lighter than the body with a lit rim that stops short of white, so they keep their bevel; undersides and seams are shaded darker; dim text moves toward the ground by the same step as on a dark device, and reads about 6:1 on it. Screens are paper glass printed in ink, because a glow on a pale body is a smudge. What's lit (an LED, the current rail) is still the accent, held to 3:1 on every ground, so on is brighter than off; the text it prints (a readout, a count, a current tab) and the focus ring are the accent's ink, a step deeper and held to AA, in the new accent-ink role. The primary cap is the same cap as a dark device's, the accent with a light label: its label is the new primary-cap-ink role, and progress cells, loader dots and a meter's fill, the same plastic, read 3:1 on the page. A neutral cap or a slider that fills with it under its own dark label fills with the new pour-* roles, the accent's pale stops. Shadows are drawn at half their weight, in a deep colour of the body's own hue (--echo-cast-ink) instead of black. Every guarantee holds as it does on a dark device, and the contrast sweep now runs on light bodies too. A dark seed makes exactly the theme it did before, and the new roles equal the ones they stand for there. The components that mixed a recess toward black, painted paper in the text colour or lit a pillow of light with it read the theme's new --echo-shade-ink, --echo-paper-stock and --echo-paper-ink instead, with the old value as the fallback, and a reflective screen reads --echo-screen-*; the components that print a lit label read --echo-primary-cap-ink and --echo-accent-ink the same way; every rail is drawn in the glow, and every focus ring, the ring recipes included, in the ink. style use wears a light style now, and style check says which device a style makes. A dark screen tint on a light body is still refused: one text colour can't serve both, and the theme says so.
v0.2.0 · 2026-10-04 · AddedPatchBay: connecting things to things. Sockets down each side and a cable between every connected pair, for mapping an import's columns to fields or routing events to channels. Each source has a Select that says where it goes, and that's the control; the cables draw what the Selects say, drop into place and sway once, and can be dragged from socket to socket. On a narrow screen only the Selects stay.
v0.2.0 · 2026-10-04 · ChangedComments only, no behaviour change. Comments in the component source used to cite documents, milestones and ticket numbers from Echo's own planning, none of which exist in your project. The citations are gone and the sentences around them stay. Where a comment was only a citation, it now says what it meant. Three development warnings (HardwareButton's engraved/caption checks and StatusDot's missing-label check) also dropped the ticket code at the end of the message. echo-ui diff will show changes in most items; none of them are to code.
v0.2.0 · 2026-10-04 · ChangedAn item's version is now a function of declared data, not of how the changelog is formatted. The version an item ships under is published once and never rewritten, and it used to be inferred from prose: a regex for a bolded "Breaking" run across the whole unreleased section, and attribution by "does a bullet mention this name in backticks". One breaking entry therefore moved every item that changed that cycle, and an entry explaining that "Menu and Sheet are unchanged here" filed itself as a change to Menu and Sheet — which it really had.
v0.2.0 · 2026-10-04 · ChangedThe agent brief says Echo has not shipped. llms.txt and the MCP server's instructions led with npx echo-ui-cli init, and that name on npm is a reserved stub with no executable — so a model following the brief wrote an install step that fails with npx's own error. The brief now opens with the caveat, and the docs carry it on every surface that shows a command. One switch (CLI_RELEASED) silences all of them at launch, and a test refuses to let one move without the others. Affects all components only in what the brief says about installing them; no item's props, CSS or rendered semantics change.
v0.2.0 · 2026-10-04 · ChangedEcho's home is echo-ui.com. The registry, the docs and the packages all move to it from echo.nawwara.studio. Nothing was published under the old host, so no echo.json anywhere points at it and there is nothing to migrate — this is the last release where that is true.
v0.2.0 · 2026-10-04 · ChangedWeights, line heights, letter-spacing, z-index, border widths and icon sizes come from the theme scales in all components, with the old value as a fallback, so components keep working with echo-ui-core@0.0.1. Strays moved to the nearest step: most by under a pixel; HardwareButton icons are 14/16/20px (were 15/17/19).
v0.2.0 · 2026-10-04 · FixedContent now reflows into a 320px screen (400% zoom) and survives a doubled browser text size (WCAG 1.4.10, 1.4.4), across all components. Select's 180px floor, NumberField's readout, Segmented and Steps as flex items, EmptyState's grid columns, and Avatar's fixed-pixel disc all gave way; Panel counts its padding inside a width you set (box-sizing: border-box), so a <Panel style={{ width: 220 }}> is now 220px wide overall rather than 260px.

Preview