TREK/plugin-sdk

trek-plugin-sdk

The SDK for building TREK plugins.

The path is four commands: create → dev → status → publish. Everything else the CLI can do is a step one of those already does for you.

Scaffold a plugin

npx trek-plugin-sdk                        # no command? a guided menu of everything below
npx trek-plugin-sdk create                 # interactive wizard (id, type, icon, permissions, egress)
npx trek-plugin-sdk create my-plugin --type widget   # or non-interactive
cd my-plugin

The wizard asks for the id, type, icon (validated against lucide), permissions, egress hosts and required addons, and offers to initialize a git repo and install dependencies for you. In a non-interactive shell (CI, pipes) every command stays flag-driven with plain output — no prompts, and machine output (entry JSON, pack --json, PR URLs) stays on stdout.

What you get runs and packs immediately — but it is not publishable yet: the README is a template and there is no screenshot. That is deliberate. Writing those is your job, and status tells you exactly what is left.

Develop with a live reload loop

dev runs your plugin locally — no full TREK needed. It injects a ctx that enforces exactly the permissions your manifest grants (an ungranted call throws PERMISSION_DENIED, so you catch missing grants), backs db:own with a real SQLite file, serves your routes and your page/widget UI, and reloads on save.

npx trek-plugin-sdk dev        # http://localhost:4317 — dashboard, routes, UI

Open /preview to see a page/widget rendered in a real sandboxed frame with a theme/accent/appearance toggle (trek.invoke() is proxied to your routes). Hit a route as an unauthenticated request with ?_anon=1. Drop a dev-fixtures.json (trips, users, config) next to your manifest to feed ctx.trips / ctx.users.

Know where you are

npx trek-plugin-sdk status        # never fails — it's a map, not a gate

status runs every check the TREK-Plugins registry enforces that can be answered without a network — which is nearly all of them — and prints the whole journey as a checklist grouped by stage (Manifest, Code, Docs, Release, Repo): what passes, what does not, and the one command to run next. Run it whenever you are not sure what to do; it deliberately never exits non-zero.

validate is the same checks with an exit code. It is the form for scripts and CI; status is the form for humans. A plugin that passes validate will pass every registry gate that does not require the tag and the release to exist — those four run in preflight, which publish does for you.

Build a native UI (page / widget)

The UI is a sandboxed, opaque-origin iframe that can't load TREK's stylesheet — so the SDK ships it. Put one line in your client/index.html <head>:

<!-- trek:ui -->

dev and pack expand it into the inlined design kit: token-driven styles that follow the host's theme and accent (glass, cards, .trek-btn, .trek-input, .trek-chip, .trek-row, hover), plus a window.trek bridge:

trek.onContext((ctx) => { /* ctx.theme, ctx.tokens, ctx.appearance, ctx.user, ctx.tripId */ })
const data = await trek.invoke('/status')   // calls your own route, host-proxied
trek.notify('success', 'Saved')

Keep UI state for this browser tab

The opaque frame cannot use browser storage directly. The bridge provides host-managed, JSON-only session state instead. It survives an iframe remount and page reload in the same browser tab, but is not durable data. Do not use it to store secrets.

// Default: this user + this plugin + this browser tab.
await trek.session.set('dismissed-onboarding', true)
const dismissed = await trek.session.get('dismissed-onboarding')

// Explicitly partition state by the trip in view (fails without a trip context).
await trek.session.set('filters', ['flight', 'hotel'], { scope: 'trip' })

get() returns undefined for a missing key. set, get, remove, and clear accept { scope: 'plugin' | 'trip' }; plugin is the default. Use your plugin's own logical key (for example reservation:88:expanded) for any finer partitioning. Each plugin or individual trip scope is limited to 32 keys, 64 characters per key, and 1 KiB per JSON value.

The kit applies the theme, mirrors the appearance flags (reduced-motion, no-transparency) and auto-reports your height. It also upgrades any native <select> into a host-styled, keyboard-accessible dropdown that matches TREK — the OS-drawn popup never could. Write a plain <select> and it just works; add data-trek-native to opt a field out. See the Plugin Development wiki for the full component + token reference.

Write a plugin

const { definePlugin } = require('trek-plugin-sdk')

module.exports = definePlugin({
  async onLoad(ctx) {
    await ctx.db.migrate('001', 'CREATE TABLE cache (k TEXT PRIMARY KEY, v TEXT)')
  },
  routes: [
    { method: 'GET', path: '/status', auth: true, async handler(req, ctx) {
      return { status: 200, headers: { 'content-type': 'application/json' }, body: '{"ok":true}' }
    }},
  ],
})

Your plugin runs in an isolated child process. ctx is the only way to reach TREK, and it grants exactly the permissions your trek-plugin.json declares — an ungranted call throws PERMISSION_DENIED.

Test without a running TREK

import { createMockHost } from 'trek-plugin-sdk/testing'

const { ctx, broadcasts } = createMockHost({
  grants: ['db:read:trips', 'ws:broadcast:trip'],
  trips: { 1: { members: [42], data: { id: 1, name: 'Japan' } } },
})
// the mock enforces the SAME permission model, so you can prove your plugin
// degrades gracefully when a permission is missing.

Capture the screenshot

The registry requires a screenshot that resolves to a real image, and the store card shows it. shot boots the dev server, renders your plugin in the same themed frame TREK uses, and writes a 1600×900 docs/screenshot.png:

npm i -D playwright && npx playwright install chromium   # once
npx trek-plugin-sdk shot                                 # --dark for the dark theme

Playwright is deliberately not a dependency of this SDK — it ships a browser, and most authors never need one. An integration plugin has no UI to render, so shot cannot help; screenshot the TREK surface your plugin changes instead.

Publish — one command

Commit and push your plugin to its public GitHub repo, then:

npx trek-plugin-sdk publish --repo you/repo --tag v1.0.0

publish is the whole release, in five steps and in this order:

1. check — every registry gate that can be checked locally
2. pack — build plugin.zip
3. release — git tag, push, and cut the GitHub release with the artifact
4. preflight — the gates that need the tag and the release to exist
5. submit — open the PR against the TREK-Plugins registry

Step 1 comes first for a reason: a GitHub release is effectively immutable, because the registry pins its sha256. If a check fails, nothing is packed, tagged, pushed or released — so you can fix it and re-run against the same version. (--no-checks skips step 1; it is an escape hatch for a re-run, never right on a first publish.)

Needs git and an authenticated gh. It prints the PR URL at the end.

Updating a listed plugin: bump version in the manifest, commit, and run publish again with the new tag — it detects the existing entry and prepends the new version, newest-first.

Prefer to drive the steps yourself? They still exist individually — pack, release (pack → GitHub release → entry), preflight, submit (opens the PR), and entry (just prints the JSON).

Signing (recommended — publish offers it)

In a terminal, publish asks whether to sign, and creates the key for you if you have none — you don't have to know --sign or keygen exist. Scripts and CI are never prompted: pass --sign.

A signature proves the artifact came from you, not just that its bytes match what the registry saw. Signing is dependency-free Ed25519 over the artifact bytes.

It is a one-way door you may walk through late:

• Unsigned throughout is fine — the sha256 pin is the only guarantee, and TREK accepts it.
• Unsigned → signed later breaks nobody. Nothing is pinned until a signed version installs, so adding a key at v1.4.0 is a real option, not a lost cause.
• Signed → unsigned is refused forever, on every instance that already has the plugin. publish refuses that at step 1, before anything is tagged or released.

So back the key up (~/.trek-plugin/signing.key). Losing it means you cannot ship an update to your own plugin without a registry maintainer override.

npx trek-plugin-sdk publish --repo you/repo --tag v1.1.0 --sign   # or just answer the prompt

Exports

• definePlugin(def) + all the plugin types (PluginContext, PluginRoute, PluginJob, PhotoProvider, CalendarSource).
• PLUGIN_API_VERSION — embed as apiVersion in your manifest.
• validateManifest(json) — the manifest rules the server loader uses.
• createMockHost(opts) (from trek-plugin-sdk/testing).
• TREK_UI_CSS, TREK_THEME_JS, TREK_UI_MARKER, injectTrekUi(html) — the design kit, for authors who inline it themselves (a bundler, a custom build). Most plugins just use the <!-- trek:ui --> marker instead.

Commands

Run any of these with npx trek-plugin-sdk <command> (or the short trek-plugin bin if you install the package). trek-plugin help <command> — or trek-plugin <command> --help — prints a full page for any of them.

The path:

• create [name] [--type t] [--template blank|notification-channel] [--interactive] — scaffold a plugin; a wizard if you omit the name.
• dev [dir] [--port 4317] — run locally with a real request loop, SQLite db:own, and hot reload.
• status [dir] — where am I? what's left? Every offline registry gate as a checklist, plus the next command. Never fails.
• publish [dir] --repo o/n --tag vX [--sign [key]] [--no-checks] [--no-preflight] — the lot: check → pack → release → preflight → open the PR. In a terminal it offers to sign (and makes you a key); scripts pass --sign.

Also:

• validate [dir] — the gate: the same checks as status, but it exits non-zero.
• pack [dir] [--out plugin.zip] [--json] — build the artifact, print sha256 + size. Refuses a plugin that could not load; does not enforce the publish gates, because packing is how you sideload a plugin to try it.
• shot [dir] [--port 4317] [--out docs/screenshot.png] [--dark] [--no-serve] — capture docs/screenshot.png. Needs Playwright.
• keygen [--key file] — create an Ed25519 signing key.
• sign [zip] [--key file] — print a signature + public key for an artifact.
• entry --repo o/n --tag vX [--merge f] [--sign [key]] [--out f] — emit the registry entry JSON.
• preflight [dir] --repo o/n --tag vX [--entry f] [--all] — the registry checks that need the network: the tag resolves to the pinned commit, the released artifact downloads and hashes, the id is not bound to another owner, and an update does not drop or rotate a published signing key.
• submit [dir] --repo o/n --tag vX [--registry o/n] [--draft] — open the registry PR for you.
• release [dir] --repo o/n --tag vX [--sign [key]] [--merge f] — pack → GitHub release → entry, without opening the PR.

Update notice

Both CLIs (trek-plugin and create-trek-plugin) tell you when a newer SDK has been published. This matters more than the usual "you're on an old version" nag: the registry entry format, the manifest rules and the permission catalog all move with the TREK host, so a stale SDK can pack and submit an entry that today's registry CI rejects.

It is powered by update-notifier, the standard for npm CLIs:

• At most once every 24 hours, a detached background process asks registry.npmjs.org for this package's latest version and caches the answer under $XDG_CONFIG_HOME/configstore/ (or ~/.config/…).
• Your command never waits for it — the notice is printed from that cache, so a fresh install learns about an update on a later run.
• The notice goes to stderr, so pack --json and entry keep piping clean JSON.

The request is an unauthenticated GET for a public package — the same one npm install makes (npm's servers see your IP, as for any download). TREK has no telemetry, and this isn't any. To turn it off:

export NO_UPDATE_NOTIFIER=1

It is already silent in CI (any CI env var), under NODE_ENV=test, and whenever stdout isn't a terminal (i.e. when piped or redirected).

The SDK tooling in this repo is MIT. Your plugin is your own code under your own license.