Stacks Plugins

Stacks Plugins and the Preload Chain

Stacks has no @stacksjs/plugins package. "Plugins" here means Bun's native plugin API plus the two modules bunfig.toml preloads before any Stacks code runs. If you are chasing "why is User undefined in this command" or "why did .env not decrypt", this is the skill.

Key Paths

• Preload declaration: bunfig.toml (preload, at the root and under [test])
• Env plugin: storage/framework/core/env/plugin.ts
• Framework preloader: storage/framework/defaults/resources/plugins/preloader.ts
• Static-serve plugin: bunfig.toml, [serve.static] plugins = ["bun-plugin-stx"]

The preload chain

bunfig.toml preloads two modules, in this order:

preload = [
  "./storage/framework/core/env/plugin.ts",
  "./storage/framework/defaults/resources/plugins/preloader.ts",
]

1. Env plugin loads .env and decrypts dotenvx-style encrypted values, so everything downstream reads plaintext from process.env.
2. Preloader loads env files for the resolved environment, then injects the framework's server auto-imports into globalThis.

Order is load-bearing: the preloader reads decrypted secrets, so it has to run second.

Tests preload a different pair - the env plugin and tests/setup.ts - so the suite gets production env semantics without the auto-import graph.

What the preloader does

1. Resolves the environment

Before loading any .env file it works out APP_ENV, because that decides which file gets decrypted:

• deploy staging and deploy --staging both resolve to staging. Both forms are handled; CI uses the flag form.
• cloud:remove, cloud:destroy, cloud:cleanup, undeploy force production.
• Bare deploy defaults to production.

2. Loads and decrypts env files

Gated on isRepl / isPostinstall only - never on the fast-command list below. Fast commands (migrate, build, seed, ...) genuinely need decrypted config; gating them here caused stacksjs/stacks#2048, where an encrypted .env.<env> silently never decrypted even with the key present.

Postinstall skips because @stacksjs/env may not be linked yet mid-install.

3. Injects auto-imports into globalThis

Loads ~24 framework packages plus everything in app/Jobs/ and resources/functions/, assigning every named export onto globalThis. That is why await User.find(1) and response.json(...) work in an action with no import statement. See stacks-auto-imports for the full manifest.

A protectedGlobals set guards the runtime: process, fetch, Promise, Bun, console and friends are never overwritten, whatever a package exports.

The fast-command skip (the usual gotcha)

Auto-import injection is skipped when the first CLI argument matches:

dev  build  test  lint  migrate  fresh  seed  generate  make
key:generate  scaffold:crud  version  help  --version  -v  --help  -h

Prefix matches count, so generate:migrations skips along with generate.

Two reasons: cold-start speed, and correctness. Codegen commands must not pull the router and ORM graph in before bun-query-builder can diff schemas - a broken @stacksjs/bun-router install used to make generate:migrations exit 1 with no output at all, because the preloader died loading @stacksjs/router.

Consequence: inside those commands, framework globals do not exist. Import what you need explicitly.

The REPL skips too (!process.argv[1]), as does anything running under npm_lifecycle_event === 'postinstall'.

Opting back in

The preloader exports loadAutoImports() so a server entrypoint can pull the graph in deliberately:

const { loadAutoImports } = await import('../../../defaults/resources/plugins/preloader.ts')
await loadAutoImports()

dev/api.ts does exactly this. Bun consumes --watch, so a directly-run server script sees an empty argv.slice(2) and would otherwise be indistinguishable from a bare invocation.

Writing a Bun plugin

Use Bun's native API directly - there is no framework wrapper to import:

import { plugin } from 'bun'

plugin({
  name: 'my-loader',
  setup(build) {
    build.onLoad({ filter: /\.custom$/ }, async (args) => {
      const contents = await Bun.file(args.path).text()
      return { contents: transform(contents), loader: 'ts' }
    })
  },
})

Register it by adding the module to preload in bunfig.toml. A plugin only affects the process that preloaded it.

Gotchas

• No @stacksjs/plugins package. Import plugin from bun.
• Preload order matters. Env decryption has to precede the preloader.
• Fast commands have no globals. If a make:* or generate:* command needs a framework symbol, import it - do not rely on auto-imports.
• bun-plugin-stx is a static-serve plugin, wired through [serve.static] plugins in bunfig.toml. The preloader's own import 'bun-plugin-stx' line is commented out; stx compilation in the dev server runs through the stx package, not that import.
• Preloader failures are silent per package. Each import sits in its own try {} catch {}, so a package that fails to build leaves its globals undefined instead of crashing the process. A mysteriously undefined global is usually an unbuilt package - check storage/framework/core/<pkg>/dist.
• Adding a global? Export it from a package already in the preloader's list, or from resources/functions/, then run buddy generate --types so the declarations match the runtime.