// Plugin development

manifest reference

the full manifest.json schema as a reference.

manifest reference

a .kern file is a zip archive containing manifest.json (required), an optional dist/index.js esm ui bundle, an optional dist/index.css, and any other assets the bundle references.

the manifest declares metadata, a dynamic config form, lifecycle commands, starter files, and ui tabs.

full example

jsonc
{
  "id": "web_api",
  "displayName": "Web API Server",
  "version": "1.0.0",
  "author": "ellipog",
  "description": "Run a Node.js/Express web API with env-based config, health checks, and pm2 or nodemon for hot reload.",
  "uiEntry": "dist/index.js",

  "configSchema": [
    { "key": "port", "label": "Port", "type": "text", "default": "3000" },
    { "key": "log_level", "label": "Log Level", "type": "select",
      "options": ["debug","info","warn","error"], "default": "info" }
  ],

  "lifecycle": {
    "start": { "command": "node", "args": ["{{userOverrides.entry}}"] },
    "start.nodemon": { "command": "nodemon", "args": ["{{userOverrides.entry}}"], "useShell": true }
  },

  "scaffold": {
    "env": { "path": ".env", "content": "PORT={{userOverrides.port}}\nLOG_LEVEL={{userOverrides.log_level}}\n" },
    "readme": { "path": "README.md", "content": "Web API ({{userOverrides.port}})…" }
  },

  "tabs": [ { "id": "setup", "label": "Setup" }, { "id": "logs", "label": "Logs" } ]
}

field reference

field	type	required	notes
`id`	string	yes	unique, lowercase, underscores. the registry key.
`displayName`	string	yes	human name.
`version`	string	yes	semver.
`author`	string	yes	a github handle. the official plugins are published by `ellipog`.
`description`	string	yes	one-liner for cards/detail.
`uiEntry`	path	no	`dist/index.js` — the esm bundle exposing `mount(hostApi)`.
`configSchema`	field[]	no	the dynamic config form (see `config-schema`).
`lifecycle`	object	no	named lifecycle steps (see `lifecycle`).
`scaffold`	object	no	starter files written into a fresh instance (see `scaffold`).
`tabs`	tab[]	no	declarative tabs the plugin registers in the detail view.

// warn

id must be lowercase with underscores only. web_api is valid; Web-API is not.

← prevgetting starteddownload kern, register a folder, start an instance.next →lifecyclestart, stop, restart, install — commands and templating.

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