Files
bflatastic 01bc5a9dac M11: plugin installs saved at once; directory and library requests off the UI thread
- **Installed plugins survive a crash.** Importing, installing, updating or removing a plugin, and a
  plugin changing its settings, now sets `Runtime::unsaved`; at the end of each frame the app hands
  the preferences to a new `Services::save_prefs`, and the desktop app writes `state.json` at once
  (temporary file + rename, the same atomic write the quit path uses, now shared). Nothing waits for
  quit any more.
- **The UI never waits on the network.** New `Session::start_background(id, params)`: the command
  runs as usual until it makes a server request; the request goes out on the link's own thread
  (`LiveLink::background`, implemented by the desktop `NetLink` with one short-lived thread per
  request) and the command stops; when the answer arrives (`Event::Net`, taken by `live_poll`, which
  the network's waker already triggers) the command runs again from the start on the file it
  started on, answered from the answers so far, until it needs no new request. All server requests
  go through one funnel (`Session::net`), so `plugin.directory.*`, `library.publishToServer`,
  `library.add` (links), `library.usage` and library fetches work this way without being split.
  A re-run of `library.publishToServer` caches the library it actually sent (a fresh copy differs
  in its time and, on a first publish, its id). One job per command; `cancel_background` drops a
  late answer.
- **UI:** `FigApp::run_background(ctx, id, params, done)` with a boxed completion. Manage plugins >
  Browse shows "Fetching from the server..." with Cancel instead of Browse; the install confirmation
  shows "Installing..." with Cancel and stays open until the download is in (an error leaves it open
  to retry); row buttons wait during an install; closing the window cancels. Assets > Libraries:
  Publish to server shows "Publishing..." + Cancel, Show usage and pasting a team library link show
  "Fetching from the server..." + Cancel. No polling repaints: the window draws again when the
  answer's waker fires; pending state is a scan of a short Vec, no per-frame allocation.
- **Programmatic callers are unchanged:** MCP, CLI, control channel and scripts still run the same
  commands synchronously (and the browser link, which has no background requests, too).
- New string "Installing..." (en/es); docs: plugins.md (immediate saves, Browse/Install never wait),
  server.md (team library requests never wait).
2026-10-12 06:15:00 +07:00

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FigCraft plugins

A FigCraft plugin is a WebAssembly module with a small JSON manifest. It acts on the document only through FigCraft's commands, the same ones the menus, the CLI, the control channel and the MCP server run (figcraft-cli commands lists them), so a plugin can do what a script can do, within the permissions its manifest asks for, and nothing more.

  • Sandboxed. Plugins run in wasmi, a pure-Rust WebAssembly interpreter (no JIT), in the desktop app and in the browser build alike. There is no WASI: no file system, network, clock or randomness. A run has an instruction budget (fuel) and a memory cap, so an endless loop or a runaway allocation fails that run, not the app.
  • One undo step. Everything a run does is one step in the undo history, named after the plugin; so is everything one callback from its panel does. When a run or a callback fails (the plugin returns an error, traps, panics or runs out of fuel or memory), the document, selection and page are put back as they were.
  • Panels and settings (API 2). A plugin can show a small panel of its own while it runs: FigCraft draws its fields and buttons with its own widgets and calls the plugin back when one is used. A plugin can also keep settings from one run to the next.
  • Widgets (API 3). A plugin can put a layer of its own on the canvas: it describes the layer (frames with auto layout, text, shapes, images), FigCraft builds it, and a click on one of its parts calls the plugin back to redraw it from its state, which is kept in the document.
  • Permissions. The manifest says whether the plugin only reads the document or may edit it, and can narrow the commands it may call. FigCraft enforces both.
  • Distribution. A team's own figcraft-server can keep a plugin directory: plugins are published to it with the server's key, browsed and installed from Plugins ▸ Manage plugins, and updated when a newer version is published (see Plugin directories). No third-party service is involved.

Using plugins

  • Plugins ▸ Development ▸ Import plugin from manifest… picks a figcraft-plugin.json. The plugin is kept in the preferences and its module is read again on every run, so a rebuilt development plugin runs its new code without importing it again.
  • The desktop app saves the preferences the moment a plugin is imported, installed, updated or removed, or changes its settings (a temporary file renamed over the old one), so a crash or a killed app never loses them; it doesn't wait until it quits.
  • The installed plugins head the Plugins menu: a plugin with one command is an item, one with several a submenu. A command with parameters (an ellipsis after its name) first opens a small form with a field per parameter, drawn with FigCraft's own widgets; Run runs it.
  • Plugins ▸ Run last plugin (⌥⌘P on macOS, Ctrl+Alt+Shift+P on Windows and Linux, where Ctrl+Alt+P is Pixel preview) runs the last plugin command again with the same parameters.
  • Plugins ▸ Manage plugins… has two tabs. Installed lists the installed plugins (version, access, where each comes from: its manifest path or the server it was installed from) with a Remove button for each, and an Import button. Browse shows a server's plugin directory, with Install, Update and Remove (see Plugin directories).
  • Plugins ▸ Widgets lists the installed widget plugins; picking one puts its widget in the middle of the view.

A message the plugin shows (notify) appears as a toast; so does a text result.

Plugin panels. A plugin written for API 2 can show a panel while it runs: a floating window, first placed beside the properties panel (drag its title bar to move it), with the plugin's notes, fields (text, number, checkbox, menu, list, colour) and buttons, drawn with FigCraft's own widgets and named for screen readers. A colour field's swatch opens FigCraft's colour picker (the plugin hears of the colour when a drag in the picker ends); its hex can also be typed. Pressing a button or changing a field calls the plugin back with every field's value; what that callback does is one undo step (none when it changes nothing), and the plugin can update the panel or close it. The module stays loaded while its panel is open, so the plugin keeps its state between callbacks. Closing the window ends the plugin's session. Each plugin has at most one panel, and the panels of different plugins open side by side (leftwards from the first, three to a row); running a plugin again replaces its own panel. An open panel costs nothing while nobody uses it (no frames are drawn).

Widgets. A widget is a frame on the canvas that belongs to its plugin. It moves, copies, deletes, exports and undoes like any layer, as one layer: the layers inside it are locked. Clicking one of its parts that the plugin made clickable (with the Move tool; the pointer turns into a hand over them) calls the plugin back, which redraws the widget; that click is one undo step. Dragging moves the widget instead, and Shift- or Cmd-clicks only select. Each widget keeps its plugin's id and its state (a small JSON object) in its own layer data, so a saved file, a copy, an undo step or a live session carries the widget as it is, and a copy is a widget of its own. A widget whose plugin isn't installed stays as it was drawn; clicking it says the plugin is missing.

In a presented prototype (the presenter or the preview pane) clicks on a widget's clickable parts call its plugin back the same way, with the same limits, but on the prototype's own copy of the file: the widget changes in the prototype only, the file and its undo history stay as they are, and restarting the prototype starts the widget over. An interaction on the clicked layer wins over the widget.

If a callback fails, it is rolled back and its message shown; a plugin that returned an error keeps its panel, one that crashed or ran out of fuel or memory loses it.

From scripts, the CLI and MCP the same commands apply, panels included:

{"command": "plugin.import", "params": {"path": "plugins/tidy-names"}}
{"command": "select.all", "params": {}}
{"command": "plugin.run", "params": {"id": "org.figcraft.examples.tidy-names", "command": "tidy", "params": {"case": "Title Case"}}}
{"command": "plugin.import", "params": {"path": "target/plugins/dist/swatch-grid"}}
{"command": "plugin.run", "params": {"id": "org.figcraft.examples.swatch-grid", "command": "panel"}}
{"command": "plugin.event", "params": {"id": "org.figcraft.examples.swatch-grid", "control": "palette", "value": "Ocean"}}
{"command": "plugin.event", "params": {"id": "org.figcraft.examples.swatch-grid", "control": "generate"}}
{"command": "plugin.close", "params": {"id": "org.figcraft.examples.swatch-grid"}}
{"command": "plugin.import", "params": {"path": "target/plugins/dist/counter"}}
{"command": "widget.insert", "params": {"plugin": "org.figcraft.examples.counter", "x": 0, "y": 0}}
{"command": "widget.list", "params": {}}
{"command": "widget.click", "params": {"id": 12, "target": "increment"}}

figcraft-cli run script.jsonl --in design.figcraft --out tidy.figcraft runs that headless; over MCP, run_command takes the same ids. A session started by the CLI or the MCP server starts with no plugins: import them in the script.

Command Params Does
plugin.list {} {plugins: [{id, name, version, description, main, api, permissions, commands, path, loaded}], last: {id, command}}
plugin.import {path} or {manifest, wasm} path is a figcraft-plugin.json or its folder. Without files (the browser, tests), pass the manifest (an object or JSON text) and the module as base64 wasm; such a plugin lasts for the session only. A plugin with the same id is replaced. The module is checked first.
plugin.remove {id} Uninstalls it.
plugin.run {id, command?, params?, fuel?} Runs a command (default: the first) with its parameters checked against the manifest and the missing ones filled with their defaults; fuel lowers the instruction budget (for the panel's callbacks too). Returns {plugin, command, output, logs, calls, fuel, panel}; output is the plugin's result, parsed as JSON when it is JSON; panel is the plugin's open panel (as plugin.ui returns it) or null.
plugin.ui {id?} Plugin id's open panel: {plugin, command, title, controls, values} (values: every field's current value by name), or null. Without id, the panel opened last.
plugin.event {id, control, value?} Uses a control of plugin id's open panel, as a click would: a button (no value), or a field set to value (checked like a parameter: a number is clamped, a list or menu value must be one of its options, a colour must be hex). The plugin is called back; returns like plugin.run.
plugin.close {id} Closes plugin id's panel and ends its session. {closed} says whether one was open.
plugins.runLast {} Runs the last plugin command again.
plugins.manage {} Opens the Plugins window; returns the list like plugin.list.
widget.insert {plugin, x?, y?, fuel?} Puts widget plugin plugin's widget on the current page, its top-left at x, y (default: centred in the view), and selects it; the plugin draws it. One undo step. Returns {id, plugin, state, targets, output, logs, calls, fuel}: targets are the names of its clickable parts.
widget.click {id, target, fuel?} Clicks part target of widget id (or of the widget a layer id is in), as a click on the canvas would: the plugin is called back and redraws it. One undo step; returns like widget.insert.
widget.list {} {widgets: [{id, plugin, name, page, state, targets}]}: every widget in the file.
plugin.directory.list {server?, query?} The plugin directory at server (ws://host:port/; default: the one browsed last): {server, plugins: [{id, name, version, description, author, api, access, commands, widget, bytes, sha256, published, versions, installed, update}]}, the latest version of each plugin whose id, name, description or author contains query. installed is the installed version (or null), update whether the listed one is newer.
plugin.directory.install {id, version?, confirm, server?, sha256?} Downloads version version (default: the latest) and installs it, or updates the installed one. confirm must be true (installing runs the plugin's code: show its permissions first); without it nothing is downloaded. The download must match the SHA-256 the directory lists (and sha256, the one shown, when given). Returns {installed, name, version, permissions, sha256, path, source, replaced}.
plugin.directory.publish {path | plugin, server} Publishes a plugin folder (or its figcraft-plugin.json), or an installed plugin, as a new version. server carries the server's key: ws://host:port/?key=…. Returns {published, server}.
plugin.directory.unpublish {id, version?, server} Removes one version (default: every version) from the directory; needs the key. Returns {id, removed}.

Plugin directories

A figcraft-server (server.md) can keep a directory of plugins for a team. Anyone who can reach the server may browse it and install from it; only whoever has the server's key may publish to it or unpublish from it. There are no accounts: the server's operator decides who gets the key and moderates what's there.

Installing. In Plugins ▸ Manage plugins… ▸ Browse, type the server's address (ws://host:47900/, or wss://… behind TLS) and press Browse: nothing is fetched before that. The list shows each plugin's latest version, author (as the publisher typed it), size and the access it asks for; the search filters it. Install opens a confirmation that lists what the plugin asks permission to do (read or edit the document, the commands it may call, whether it draws a widget), the server it comes from and its SHA-256; only its Install button downloads and installs it. The app never waits for the server: while the listing or the download is on its way, Browse shows "Fetching from the server…" and the confirmation "Installing…", each with Cancel, and the rest of the app keeps working (closing the window cancels too). The window is drawn again only when the answer arrives. Scripts, the CLI, the control channel and the MCP server get their answer from the same commands as before, waiting for it. The download must match the SHA-256 the directory lists, and the bundle is then checked like an imported plugin (manifest, plugin API version, the module compiled but not run, asset names) before anything is written. A plugin installed this way runs in the same sandbox, with the same limits and its manifest's permissions, as any other.

The desktop app keeps such plugins per user, beside its settings (Plugins/ in FigCraft's settings folder: %APPDATA%\FigCraft on Windows, ~/Library/Application Support/FigCraft on macOS, ~/.config/FigCraft elsewhere), each in a folder of its own named by a hash of its id, with its module and its assets. The CLI and the MCP server install for the session only.

Updating. When the directory has a newer version than the one installed, the plugin's row offers Update, with the same confirmation (the permissions may have changed). Browsing again is the update check; nothing checks in the background. Remove uninstalls it and deletes its folder.

Publishing. A plugin folder holds figcraft-plugin.json, the module its main names and, if you like, an assets/ folder of up to 32 plain files (an icon, a licence) that are installed with it. Publish it with the server's key:

FIGCRAFT_SERVER_KEY=<key> figcraft-cli plugin publish target/plugins/dist/counter --server ws://host:47900/

(the key may also be in the address, ?key=…, but the environment keeps it out of your shell history), or plugin.directory.publish {path, server} from a script or MCP. The server checks the whole bundle before keeping it, refuses a version that isn't newer than the one it has, and lists the new version at once. plugin.directory.unpublish (or the operator's figcraft-server plugins remove) takes a version, or the whole plugin, down; installed copies keep working.

In the browser the directory isn't available yet: the browser build's network link has no plugin directory requests (plugin.directory.* says so). Import plugins with plugin.import {manifest, wasm} there.

The manifest: figcraft-plugin.json

{
  "id": "org.figcraft.examples.swatch-grid",
  "name": "Swatch grid",
  "version": "1.0.0",
  "description": "Makes a grid of colour swatches from a palette of hex colours.",
  "main": "swatch_grid.wasm",
  "api": 1,
  "permissions": {
    "access": "write",
    "commands": ["view.get", "shape.rectangle", "text.create", "select.set"]
  },
  "commands": [
    {
      "id": "grid",
      "label": "Swatch grid…",
      "params": [
        { "name": "palette", "label": "Palette", "type": "text", "default": "#FF5A5F, #00A699" },
        { "name": "columns", "label": "Columns", "type": "number", "default": 3, "min": 1, "max": 24 },
        { "name": "labels", "label": "Label each swatch", "type": "boolean", "default": true }
      ]
    }
  ]
}
Field
id Required. 1–128 letters, digits, ., -, _; a reverse domain name is a good choice.
name Required. Shown in the Plugins menu (64 characters at most).
version, description Optional text. A plugin published to a directory needs a version of one to four numbers (1.2.0), each version newer than the last.
author Optional: who made it, as you type it (64 characters at most); plugin directories show it.
main Required. The module, a .wasm path relative to the manifest, inside its folder.
api The plugin API version the plugin was written for: 1 (the default), 2 (panels and settings) or 3 (widgets). A manifest asking for a newer one than FigCraft runs is refused, so a plugin that needs panels or widgets fails clearly on an older FigCraft.
widget API 3: true when the plugin draws a widget (it's listed in Plugins ▸ Widgets).
permissions.access read (the default): commands that leave the document as it is; such plugins also run from Dev Mode's Inspect tab. write: edits too.
permissions.commands Optional allowlist: exact command ids or prefixes ending in * (node.*). Empty: any command the access allows.
commands The menu commands, each {id, label, params?}. Without any, the plugin has one, run, unless it's a widget (a widget needs no command).
params[] {name, label?, type, default?, options?, min?, max?}; type is text, number (clamped to min/max), boolean, select (one of options, a menu), list (one of options, shown as a list) or color (hex, #RRGGBB or #RRGGBBAA). A default that doesn't fit is dropped.

What a plugin can't do

Whatever its manifest says, FigCraft refuses these calls (the plugin gets the refusal as an error it can handle):

  • files and the app: file.*, app.*, pref.*, help.*, library.add, libraries.*, image.place with a path (pass the image as base64 data instead), view.theme*;
  • other documents and the version history: doc.* and version.* (except doc.list and version.list);
  • the undo history and nesting: edit.undo, edit.redo, edit.repeat, command.batch (a run is already one undo step), plugin.* / plugins.* (no plugin runs another) and widget.*;
  • writing layer data whose key starts with figcraft.widget (a widget's own data: no plugin can forge a widget or change another one's state);
  • commands that open a dialog or panel (for example object.rename without a name, which would start renaming in the layers panel): the call is undone and refused;
  • for a read plugin, any command that changes the document (checked before the call for commands that make an undo step, and after it for the rest: a change is undone and refused).

Limits per run, and again per panel callback: 1,000,000,000 fuel (about a second or two of plain WebAssembly in a debug build, far less in a release build), 64 MB of memory, 100,000 host calls (each also costs 10,000 fuel), 16 MB per string either way, 1,000 log lines, and modules up to 16 MB. A panel spec is at most 64 KB with 64 controls; settings are at most 64 KB per plugin (keys and JSON values), keys 1–128 characters. A widget callback gets the same limits; its description is at most 4 MB with 256 layers nested 16 deep, its state at most 16 KB (keys 1–128 characters), and its images 1 MB each, 2 MB together and 4096 pixels on a side.

ABI (version 3)

Version 2 adds panels and settings to version 1, and version 3 adds widgets; a version 1 or 2 module runs unchanged and gets the input it always got. Strings are UTF-8 (ptr, len) pairs in the plugin's linear memory; all values are i32.

The module exports memory and figcraft_run(input_len) -> status. When figcraft_run starts, the reply buffer holds the input JSON, input_len bytes:

{"api": 1, "command": "grid", "params": {"palette": "#FF5A5F", "columns": 3, "labels": true}, "selection": [12, 15]}

api is the manifest's. When the plugin's panel calls it back, figcraft_run runs again in the same instance (its memory as the last call left it) with the event and every field's value added:

{"api": 2, "command": "panel", "params": {}, "selection": [], "event": {"control": "generate", "value": null}, "values": {"palette": "Ocean", "columns": 3, "labels": true}}

When its widget is inserted or clicked, figcraft_run runs in a fresh instance (nothing is kept from one call to the next: a widget's state is all it remembers, so the same state and click always give the same widget) with widget added: the widget's layer id, its state (an empty object for a new widget) and what was clicked (event is null when it's inserted):

{"api": 3, "command": "widget", "params": {}, "selection": [], "widget": {"id": 12, "state": {"count": 2}, "event": {"target": "increment"}}}

It returns 0 for success; anything else fails the run (and rolls it back), with the text passed to set_output as the error message.

The module may import these functions from the module figcraft (anything else, WASI included, is refused when the plugin is imported):

Import Signature Does
call (cmd_ptr, cmd_len, params_ptr, params_len) -> status Runs a command with JSON params (empty: {}). 0: done, the reply holds its result JSON. 1: refused or failed, the reply holds the message.
selection () -> len The reply becomes the selected layer ids, a JSON array.
reply_len () -> len The reply's length in bytes.
reply_read (ptr, len) -> copied Copies up to len bytes of the reply to ptr.
log (ptr, len) A line of the run's log (returned in logs, and written to FigCraft's log).
notify (ptr, len) A short message for the user (a toast in the app).
set_output (ptr, len) The run's result (JSON or text), or its error message when it fails.
ui_show (ptr, len) -> status API 2. Shows the plugin's panel, or replaces the one showing (the panel spec below, as JSON). 1: the spec is invalid, the reply says why.
ui_close () API 2. Closes the panel when the call returns.
setting_get (key_ptr, key_len) -> status API 2. 0: the reply holds the setting's JSON. 1: there is none.
setting_set (key_ptr, key_len, value_ptr, value_len) -> status API 2. Stores JSON under the key, for this plugin only, kept with the preferences. 1: refused (not JSON, a bad key, over 64 KB), the reply says why.
setting_delete (key_ptr, key_len) API 2. Forgets a setting.
widget_render (ptr, len) -> status API 3. Draws the widget being inserted or clicked (the widget description below, as JSON). 1: the description is invalid, the reply says why. A widget call that doesn't draw keeps the widget as it was (inserting one must draw it).

A pointer or length outside the plugin's memory traps, which fails the run. Host functions can only be called while figcraft_run runs (not from a start function). Settings are forgotten when the plugin is removed.

Panel spec

{"title": "Swatch grid", "controls": [
  {"type": "list", "name": "palette", "label": "Palette", "options": ["Sunset", "Ocean"], "value": "Ocean"},
  {"type": "note", "label": "#0A2463, #1E5AA8, #3E92CC"},
  {"type": "number", "name": "columns", "label": "Columns", "min": 1, "max": 24, "value": 3},
  {"type": "boolean", "name": "labels", "label": "Label each swatch", "value": true},
  {"type": "color", "name": "accent", "label": "Accent", "value": "#FF5A5F"},
  {"type": "button", "name": "generate", "label": "Generate"},
  {"type": "button", "name": "close", "label": "Close"}
]}

title defaults to the plugin's name. Controls are the manifest's parameter types (text, number, boolean, select, list, color) plus button and note (text in label, up to 1,000 characters, no name needed), in order, each name unique. A field shows its value; a field without one keeps what the user entered before the panel was updated, so a plugin can update a note without resetting the other fields. Buttons next to each other share a row; the first button is the primary one. FigCraft checks the whole spec (sizes, kinds, options, bounds) and drops values that don't fit their field.

Widget description

{"state": {"count": 2}, "root": {"type": "frame", "layout": "horizontal", "gap": 12, "padding": 12, "radius": 12, "fill": "#FFFFFF", "stroke": "#D9D9D9", "children": [
  {"type": "frame", "target": "decrement", "layout": "horizontal", "justify": "center", "width": 32, "height": 32, "radius": 8, "fill": "#F0F0F0",
   "children": [{"type": "text", "text": "−", "size": 16, "bold": true}]},
  {"type": "text", "name": "Count", "text": "2", "size": 24, "bold": true, "color": "#1E1E1E"},
  {"type": "image", "data": "iVBORw0KGgo…", "width": 24, "height": 24}
]}}

state is the widget's new state, a JSON object (left out: it keeps the one it has). root is the widget itself, a frame; FigCraft replaces everything inside it with the layers described and keeps the widget where it is (and its size, unless the description gives one). Every layer has a type (frame, text, rectangle, ellipse, image) and may have a name, a target (clicking it calls the plugin back with that name: letters, digits, ., -, _), x and y (in its frame, ignored in auto layout), width and height, fill and stroke (hex colours), strokeWeight, radius (frames, rectangles, images) and opacity. A frame may have layout (horizontal or vertical), gap, padding, justify and align (min, center, max: along and across the layout) and children; with auto layout it hugs its contents on an axis without a size. A text has text, size, color and bold (with a width it wraps). An image has data, the image's bytes (PNG, JPEG…) as base64, usually carried in the module itself; without a size it takes the image's. FigCraft checks the whole description (kinds, sizes, numbers, colours, lengths, counts, depth, image sizes) and refuses it if anything is off.

Writing a plugin in Rust

plugins/ in the repository is a workspace of its own: plugins/sdk (the crate figcraft-plugin-sdk, no_std with alloc) wraps the ABI with serde_json, and plugins/examples has three plugins:

  • Tidy names (tidy-names): cleans up the selected layers' names (extra spaces, the "copy" left by duplicating) and optionally their letter case, inside the selection too. Two commands: one with a form (case, include layers inside), and a quick one without.
  • Swatch grid (swatch-grid, API 2): a grid of colour swatches, centred in the view, named after their colours and optionally labelled. Palettes… opens a panel with a list of built-in palettes (picking one shows its colours), columns, labels and their colour, and a Generate button; the palette picked last is remembered as a setting for next time. From hex colours… takes a palette of hex colours in the parameters form.
  • Counter (counter, API 3): a widget, a count between − and + buttons; each click changes the count kept in the widget's state. It only reads the document.

cargo xtask plugins (part of cargo xtask wasm and cargo xtask ci; it needs the wasm32-unknown-unknown target: rustup target add wasm32-unknown-unknown) checks, tests and builds them, and leaves each example's manifest and module side by side in target/plugins/dist/<example>/, ready to import.

A plugin of your own:

# Cargo.toml
[package]
name = "my-plugin"
version = "0.1.0"
edition = "2024"

[lib]
crate-type = ["cdylib"]

[dependencies]
figcraft-plugin-sdk = { path = "../figcraft/plugins/sdk" }

[profile.release]
opt-level = "z"
lto = true
panic = "abort"
strip = true
// src/lib.rs
use figcraft_plugin_sdk::{Input, Result, Value, call, entry, json, notify};

fn run(input: Input) -> Result<Value> {
    if input.selection.is_empty() {
        return Err("Select some layers first".into());
    }
    for id in &input.selection {
        let layer = call("node.get", &json!({"id": id}))?;
        let name = layer["name"].as_str().unwrap_or_default().to_uppercase();
        call("object.rename", &json!({"ids": [id], "name": name}))?;
    }
    notify(&format!("Renamed {} layers", input.selection.len()));
    Ok(json!({"renamed": input.selection.len()}))
}

entry!(run);

Build it with cargo build --release --target wasm32-unknown-unknown, put target/wasm32-unknown-unknown/release/my_plugin.wasm next to a figcraft-plugin.json whose main names it, and import the manifest. The SDK gives call, selection, log, notify and the Input (command, params with str/f64/bool helpers, selection, and event when the panel calls back: control, value and every field's values); returning Err fails the run and rolls it back. With "api": 2 in the manifest: show_ui(&json!({...})) and close_ui() for the panel, setting(key), set_setting(key, &value) and delete_setting(key) for settings. With "api": 3 and "widget": true: input.widget (id, state, target) when the widget is inserted or clicked, and render_widget(&json!({"state": ..., "root": ...})) to draw it. Outside WebAssembly every host call fails, so the plugin's own logic can be unit-tested with cargo test.

Any language that compiles to WebAssembly works the same way: export memory and figcraft_run, import what you need from figcraft.

Not yet

  • Distribution: directories live on your own figcraft-server; there is no public catalogue, no publisher accounts or signatures (the server's key is the publisher), no ratings, reviews or install counts, and updates are found when you browse, not in the background. The browser build can't use a directory yet.
  • Plugins written for other apps (JavaScript plugins) don't run.
  • Widgets: clicks are their only events (no text input, hover, property menu or timers), they can't open a panel, and their layers are frames, text, rectangles, ellipses and images only (no vectors, components or variables).
  • Panels: no images, sliders or free layout inside a panel.
  • Data in the document: plugins keep data on layers (pages included) with node.set {props: {pluginData: {key: value}}}; there is no separate per-document store.