Letstri Permix Permix

Permix — getting started

Docs: https://permix.letstri.dev/docs/quick-start

Upgrading from v3? Use action tuples, not { action, dataType } — https://permix.letstri.dev/docs/migration-v3-to-v4

Install

pnpm add permix
# or npm install permix / yarn add permix

1. Define the permission schema (once)

Create a shared module (e.g. lib/permix.ts). The generic on createPermix<D>() is the source of truth for all paths and rules.

Nested resources (most common):

import { createPermix } from 'permix'

export const permix = createPermix<{
  post: ['create', 'read', 'update', 'delete']
  comment: ['create', 'read']
}>()

Flat list (single resource):

export const permix = createPermix<['read', 'write']>()

Deep tree (orgs, workspaces, etc.):

export const permix = createPermix<{
  workspace: {
    billing: ['view', 'update']
    member: ['invite', 'remove']
  }
}>()

Every action you declare in D must appear in every setup() call (use false to deny).

2. Assign rules with setup

permix.setup({
  post: {
    create: true,
    read: true,
    update: false,
    delete: false,
  },
  comment: {
    create: true,
    read: true,
  },
})

• Static leaf: boolean
• Depends on resource at check time: (data) => boolean (see permix-check skill)
• Call setup after login, on route change, or when the active user/tenant changes — it replaces previous rules.

3. Optional: initial rules at construction

Skip a separate bootstrap step when rules are known upfront:

export const permix = createPermix<{
  post: ['read']
}>({
  post: { read: true },
})

permix.isReady() // true immediately

4. Reusable role presets — template

const admin = permix.template({
  post: { create: true, read: true, update: true, delete: true },
})

const member = permix.template({
  post: { create: false, read: true, update: true, delete: false },
})

// After resolving the user's role:
permix.setup(admin())

Dynamic template (parameters):

const forUser = permix.template((user: User) => ({
  post: {
    update: post => post.authorId === user.id,
  },
}))

permix.setup(forUser(currentUser))

5. Typed rules factory — createRules

Use when rules live in another file but must stay type-safe:

import { createPermix, createRules } from 'permix'

const rules = createRules<{
  post: ['create']
}>({
  post: { create: true },
})

permix.setup(rules)

6. First check

permix.check('post.read') // boolean

Before setup, check throws PermixNotReadyError. Unknown paths throw PermixRuleNotDefinedError.

7. React to permission changes (optional)

permix.hook('setup', () => {
  // re-run when rules change (e.g. refresh UI cache)
})

permix.hookOnce('ready', () => {
  // first successful setup only
})

Docs: https://permix.letstri.dev/docs/guide/events

Checklist for new apps

• Single exported permix instance (same reference everywhere)
• Schema covers every permission the app uses
• setup runs when auth/session is known
• UI waits for isReady or handles not-ready (React: permix-frontend skill)
• Server routes use middleware (permix-server skill) — never rely on client checks alone

Source: letstri/permix — distributed by TomeVault.