# Authorization Application authorization - Package: @bijectionhq/authz - Category: Authentication - Status: Reference - License: Apache-2.0 - Bijection source (repository access required): https://github.com/bijectionhq/authz/tree/3bb0fa19b552139b9d82afc4a2e329b62787f076 - Upstream: https://github.com/dbjpanda/convex-authz/tree/0717b7fbc0c0a6760261f454ba8000124a670019 - Documentation: https://docs.bijection.com/components/using - Directory: https://bijection.com/components/authz ## Get the source Bijection repository access is required. Request access at https://bijection.com/contact. ```sh git clone https://github.com/bijectionhq/authz.git cd authz git checkout 3bb0fa19b552139b9d82afc4a2e329b62787f076 ``` ## Before using this component Read the package README at the recorded revision for setup, dependencies, and API examples. Upstream documentation describes the original package and may differ from the Bijection adaptation. This is a source candidate for evaluation. Catalog inclusion does not establish npm availability or runtime qualification. Check compatibility with your SDK and deployment before adoption. External providers run their own compute. ## Upstream package documentation Recorded 2026-10-23. This describes @djpanda/convex-authz; check the Bijection adaptation separately. A comprehensive authorization component that implements RBAC, ABAC, and ReBAC (relationship-based access control) with O(1) indexed permission lookups. Inspired by Google Zanzibar, it provides role assignments, attribute-based policies, and relationship graph traversal for complex permission scenarios. Pre-computes permissions into indexed tables for instant checks while supporting scoped permissions, expiring grants, and real-time updates through Convex reactivity. ### Use cases - Building multi-tenant SaaS applications where users need different roles (admin, editor, viewer) across different organizations or teams - Implementing document or project-based permissions where access depends on relationships like team membership or resource ownership - Creating complex authorization rules that combine user attributes, resource properties, and organizational hierarchies - Supporting temporary access grants with automatic expiration for contractors or time-limited collaborations - Scaling permission checks in high-traffic applications where authorization latency must remain constant regardless of system size ### How it works You define permissions and roles in a configuration file using `definePermissions()` and `defineRoles()`, then create an `Authz` client that connects to the component. The component supports role inheritance and composition through `inherits` and `includes` properties. The system pre-computes all effective permissions into indexed tables (`effectivePermissions`, `effectiveRoles`, `effectiveRelationships`) enabling O(1) lookups via `authz.can()` and `authz.require()`. You assign roles with `assignRole()` and create relationships with `createTuple()` for ReBAC scenarios. React integration works through an `AuthzProvider` that wraps your Convex queries, providing hooks like `useCanUser()` and components like `PermissionGate`. Permission checks support wildcard patterns (`documents:*`, `*:read`) and scoped contexts where roles apply to specific resources rather than globally. The component maintains audit logs and supports expiring grants by accepting expiration timestamps. All changes trigger Convex's reactive updates, automatically refreshing UI components when permissions change. ### Upstream README # @djpanda/convex-authz A comprehensive, production-ready authorization component for [Convex](https://convex.dev) featuring **RBAC**, **ABAC**, and **ReBAC** with **O(1) indexed lookups**, inspired by [Google Zanzibar](https://research.google/pubs/pub48190/). ## Features | Feature | Description | | ---------------------- | ------------------------------------------------------ | | **RBAC** | Role-Based Access Control with scoped roles | | **ABAC** | Attribute-Based Access Control with custom policies | | **ReBAC** | Relationship-Based Access Control with graph traversal | | **O(1) Lookups** | Pre-computed permissions for instant checks | | **Type Safety** | Full TypeScript support with type-safe permissions | | **Audit Logging** | Track all permission changes and checks | | **Scoped Permissions** | Resource-level access control | | **Expiring Grants** | Time-limited role assignments and permissions | | **Convex Native** | Built specifically for Convex, with real-time updates | ## Terminology | Term | Definition | | ----------------------- | -------------------------------------------------------------------------------------------------------------- | | **RBAC** | Role-Based Access Control - permissions assigned via roles (admin, editor, viewer) | | **ABAC** | Attribute-Based Access Control - permissions based on user/resource attributes (department=engineering) | | **ReBAC** | Relationship-Based Access Control - permissions derived from relationships (member of team that owns resource) | | **Zanzibar** | Google's global authorization system, inspiration for OpenFGA and this component | | **Tuple** | A relationship triple: `(subject, relation, object)` e.g., `(user:alice, member, team:sales)` | | **Scope** | Resource-level permission context, e.g., "admin of team:123" vs global "admin" | | **Traversal** | Following relationship chains to determine inherited access | | **O(1) Lookup** | Constant-time permission check via pre-computed indexes | | **Permission Override** | Direct grant/deny that bypasses role-based permissions | --- ## Installation ```bash npm install @djpanda/convex-authz ``` --- ## Quick Start ### 1. Register the Component ```typescript // convex/convex.config.ts import { defineApp } from "convex/server"; import authz from "@djpanda/convex-authz/convex.config"; const app = defineApp(); app.use(authz); export default app; ``` ### 2. Define Your Permissions and Roles ```typescript // convex/authz.ts import { Authz, definePermissions, defineRoles } from "@djpanda/convex-authz"; import { components } from "./_generated/api"; // Step 1: Define permissions const permissions = definePermissions({ documents: { create: true, read: true, update: true, delete: true, }, settings: { view: true, manage: true, }, }); // Step 2: Define roles const roles = defineRoles(permissions, { admin: { documents: ["create", "read", "update", "delete"], settings: ["view", "manage"], }, editor: { documents: ["create", "read", "update"], settings: ["view"], }, viewer: { documents: ["read"], }, }); // Step 3: Create the authz client export const authz = new Authz(components.authz, { permissions, roles, tenantId: "my-app" }); ``` #### Role inheritance and composition Roles can be defined in terms of other roles to avoid repeating permission lists: - `**inherits**` – one parent role; effective permissions = parent’s permissions ∪ this role’s direct permissions. - `**includes**` – multiple roles; effective permissions = union of all included roles’ permissions ∪ this role’s direct permissions. Example with inheritance (admin > editor > viewer): ```typescript const roles = defineRoles(permissions, { viewer: { documents: ["read"] }, editor: { inherits: "viewer", documents: ["create", "update"] }, admin: { inherits: "editor", documents: ["delete"], settings: ["manage"] }, }); ``` Example with composition (combine roles): ```typescript const roles = defineRoles(permissions, { editor: { documents: ["create", "read", "update"] }, billing_admin: { billing: ["view", "manage"] }, billing_manager: { includes: ["editor", "billing_admin"], settings: ["view"] }, }); ``` **Note:** `inherits` and `includes` are reserved keys in role definitions; do not use them as permission resource names. ### 3. Use in Your Functions ```typescript // convex/documents.ts import { mutation, query } from "./_generated/server"; import { v } from "convex/values"; import { authz } from "./authz"; import { getAuthUserId } from "@convex-dev/auth/server"; export const updateDocument = mutation({ args: { docId: v.id("documents"), content: v.string() }, handler: async (ctx, args) => { const userId = await getAuthUserId(ctx); // Check permission (throws if denied) await authz.require(ctx, userId, "documents:update"); // Or with scope await authz.require(ctx, userId, "documents:update", { type: "document", id: args.docId, }); // Proceed with update... }, }); ``` --- ## Unified Authz v2 v2 consolidates everything into a single `Authz` class. If you previously used `IndexedAuthz`, just rename it — the constructor signature is identical. ### What changed - **One class**: `Authz` replaces both the original `Authz` and `IndexedAuthz`. O(1) reads via pre-computed effective tables are now the default. - **ReBAC on `Authz`**: `hasRelation`, `addRelation`, and `removeRelation` are available directly on every `Authz` instance. - **ABAC policy types**: Policies accept a `type` field (`"static"` or `"deferred"`). In the current implementation, both types are evaluated at read-time when `can()` is called — Convex mutations cannot call queries, so write-time evaluation is not possible. The `type` field is reserved for future optimization but currently has no behavioral difference. - `**canWithContext()`**: Check deferred ABAC policies that need runtime context (e.g. IP address, time of day). - `**recomputeUser()**`: Rebuild a user's effective-permissions table on demand — useful after a schema change or post-deploy migration. - `**withTenant()**`: Get a scoped copy of the client bound to a different tenant for cross-tenant admin operations. ### ReBAC example ```typescript // Add a relationship await authz.addRelation(ctx, { type: "user", id: userId }, "member", { type: "team", id: teamId }); // Check a relationship const isMember = await authz.hasRelation(ctx, { type: "user", id: userId }, "member", { type: "team", id: teamId }); // Remove a relationship await authz.removeRelation(ctx, { type: "user", id: userId }, "member", { type: "team", id: teamId }); ``` ### ReBAC → Permission Bridge Use `defineRelationPermissions` to automatically grant permissions when relationships are created: ```typescript import { defineRelationPermissions } from "@djpanda/convex-authz"; const authz = new Authz(components.authz, { permissions, roles, tenantId: "my-app", relationPermissions: defineRelationPermissions({ "document:viewer": ["documents:read"], "document:editor": ["documents:read", "documents:update"], "document:owner": ["documents:read", "documents:update", "documents:delete"], }), }); // Adding a relation automatically grants scoped permissions await authz.addRelation(ctx, { type: "user", id: userId }, "editor", { type: "document", id: docId }); // can() now checks relation-derived permissions — no separate hasRelation() needed const canUpdate = await authz.can(ctx, userId, "documents:update", { type: "document", id: docId }); // true // Removing the relation revokes the permissions await authz.removeRelation(ctx, { type: "user", id: userId }, "editor", { type: "document", id: docId }); ``` ### ABAC example ```typescript // Policies are always evaluated at read-time when can() is called. // The optional type field ("static" | "deferred") is reserved for future use // and currently has no behavioral effect. const policies = definePolicies({ "documents:read": { condition: (ctx) => ctx.getAttribute("verified") === true, message: "Only verified users can read documents", }, "billing:export": { condition: (ctx) => { const hour = new Date().getUTCHours(); return hour >= 9 && hour <= 17; }, message: "Billing exports only during business hours", }, }); // Use canWithContext() when request context is available const allowed = await authz.canWithContext(ctx, userId, "documents:read", undefined, { ipAllowlisted: true, }); ``` ### Post-deploy rebuild ```typescript // Rebuild a single user's effective permissions after upgrading await authz.recomputeUser(ctx, userId); ``` ### Cross-tenant operations ```typescript const otherTenantAuthz = authz.withTenant("other-tenant-id"); const allowed = await otherTenantAuthz.can(ctx, userId, "documents:read"); ``` ### Migration guide: `IndexedAuthz` → `Authz` > **Note:** `IndexedAuthz` is no longer exported in v2. The import below will fail — just replace it with `Authz`. ```typescript // Before (v1) — this import no longer works in v2 // import { IndexedAuthz } from "@djpanda/convex-authz"; // const authz = new IndexedAuthz(components.authz, { permissions, roles, tenantId: "my-app" }); // After (v2) — same constructor, just rename the class import { Authz } from "@djpanda/convex-authz"; const authz = new Authz(components.authz, { permissions, roles, tenantId: "my-app" }); ``` After upgrading, run `recomputeUser()` for each existing user to backfill the effective-permissions table: ```typescript // one-time migration mutation export const backfillEffectivePermissions = mutation({ args: {}, handler: async (ctx) => { const users = await ctx.db.query("users").collect(); for (const user of users) { await authz.recomputeUser(ctx, String(user._id)); } }, }); ``` --- ## React integration The package provides React hooks and a `PermissionGate` component so your UI can check permissions and roles reactively. Your app must expose Convex queries that wrap the Authz component (e.g. `checkPermission`, `getUserRoles`). The hooks call those queries via Convex’s `useQuery`, so permission and role changes stay up to date without polling. ### 1. Expose Convex queries Define queries that delegate to your authz client, for example: ```typescript // convex/app.ts (or similar) import { query } from "./_generated/server"; import { v } from "convex/values"; import { authz } from "./authz"; export const checkPermission = query({ args: { userId: v.string(), permission: v.string(), scope: v.optional(v.object({ type: v.string(), id: v.string() })), }, handler: async (ctx, args) => { return authz.can(ctx, args.userId, args.permission, args.scope); }, }); export const getUserRoles = query({ args: { userId: v.string(), scope: v.optional(v.object({ type: v.string(), id: v.string() })), }, handler: async (ctx, args) => { return authz.getUserRoles(ctx, args.userId, args.scope); }, }); ``` ### 2. Wrap your app with AuthzProvider Pass your Convex query refs (and optionally a default user id) to the provider: ```tsx import { AuthzProvider } from "@djpanda/convex-authz/react"; import { api } from "./convex/_generated/api"; ``` ### 3. Use hooks and PermissionGate - **useCanUser(permission, options?)** — Returns `{ allowed, isLoading, error }`. Options: `{ userId?, scope? }`. Uses `defaultUserId` from the provider when `userId` is omitted. - **useUserRoles(options?)** — Returns `{ roles, isLoading, error }`. Options: `{ userId?, scope? }`. - **useRequirePermission(permission, options?)** — Throws when the user is not allowed (use an error boundary to show a denied state). - **PermissionGate** — Renders `children` when allowed, `fallback` when denied, and `loadingFallback` (optional) while loading. ```tsx import { useCanUser, useUserRoles, useRequirePermission, PermissionGate, } from "@djpanda/convex-authz/react"; function DocumentList() { const { allowed, isLoading } = useCanUser("documents:read"); if (isLoading) return ; if (!allowed) return

You cannot view documents.

; return
{/* list */}
; } function AdminPanel() { useRequirePermission("settings:manage"); // throws if denied; wrap in error boundary return
Admin content
; } function EditButton({ docId }: { docId: string }) { return ( No access} loadingFallback={Checking…} > ); } ``` Convex’s reactivity ensures that when permissions or roles change on the backend, the hooks and `PermissionGate` re-run and the UI updates automatically. --- ## Architecture ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ @djpanda/convex-authz │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ ┌──────────────────┐ ┌──────────────────┐ ┌──────────────────────────┐ │ │ │ RBAC │ │ ABAC │ │ ReBAC │ │ │ │ Role-Based │ │ Attribute-Based │ │ Relationship-Based │ │ │ │ Access Control │ │ Access Control │ │ Access Control │ │ │ │ │ │ │ │ │ │ │ │ • Roles │ │ • User attrs │ │ • Tuples (S, R, O) │ │ │ │ • Permissions │ │ • Policies │ │ • Graph traversal │ │ │ │ • Scopes │ │ • Conditions │ │ • Inheritance │ │ │ └──────────────────┘ └──────────────────┘ └──────────────────────────┘ │ │ │ │ │ │ │ ▼ ▼ ▼ │ │ ┌──────────────────────────────────────────────────────────────────────┐ │ │ │ O(1) Indexed Permission Cache │ │ │ │ │ │ │ │ effectivePermissions │ effectiveRoles │ effectiveRelationships │ │ │ │ [user, perm, scope] │ [user, role] │ [subject, rel, object] │ │ │ └──────────────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` --- ## RBAC (Role-Based Access Control) ### Assigning Roles ```typescript // Global role await authz.assignRole(ctx, userId, "admin"); // Scoped role (e.g., admin of a specific team) await authz.assignRole(ctx, userId, "admin", { type: "team", id: "team_123", }); // With expiration (24 hours) await authz.assignRole(ctx, userId, "admin", undefined, Date.now() + 86400000); ``` ### Revoking Roles ```typescript await authz.revokeRole(ctx, userId, "admin"); // Scoped await authz.revokeRole(ctx, userId, "admin", { type: "team", id: "team_123" }); ``` ### Checking Permissions ```typescript // Boolean check const canEdit = await authz.can(ctx, userId, "documents:update"); // Throws if denied await authz.require(ctx, userId, "documents:update"); // With scope const canEditTeamDocs = await authz.can(ctx, userId, "documents:update", { type: "team", id: "team_123", }); ``` ### Checking Roles ```typescript const isAdmin = await authz.hasRole(ctx, userId, "admin"); // Scoped const isTeamAdmin = await authz.hasRole(ctx, userId, "admin", { type: "team", id: "team_123", }); ``` ### Wildcard and pattern-matching permissions Permission checks and overrides support **wildcard patterns** so you can grant or deny whole families of permissions in one go. **Pattern format:** `resource:action`. Either `resource` or `action` (or both) may be `*`: | Pattern | Meaning | Example matches | | ------------- | ----------------------------- | ------------------------------------ | | `*` | All permissions | `documents:read`, `settings:manage` | | `documents:`* | All actions on `documents` | `documents:read`, `documents:update` | | `*:read` | Read on any resource | `documents:read`, `settings:read` | | `*:*` | All permissions (same as `*`) | any `resource:action` | **Checking:** When you call `can(ctx, userId, "documents:read")` or `require(ctx, userId, "documents:read")`, the backend treats any stored role or override that *matches* that permission as granting it. So if the user has a role with `documents:`* or an override `*:read`, they are allowed for `documents:read`. **Allocation:** You can pass a pattern into `grantPermission` and `denyPermission`: ```typescript // Grant all document actions await authz.grantPermission(ctx, userId, "documents:*", undefined, "Full document access"); // Deny read on any resource await authz.denyPermission(ctx, userId, "*:read", undefined, "Read access revoked"); ``` **Role definitions:** When the component evaluates permissions, it matches the requested permission against each role’s permission list using the same pattern rules. So if a role’s permissions include `"documents:*"` (in the flattened role–permission map), then `can(ctx, userId, "documents:read")` is allowed. With `defineRoles` you typically list concrete actions per resource (e.g. `documents: ["read", "update"]`); to use patterns in roles you would supply a role-permission map that includes pattern strings for that role. **Client-side helper:** To test whether a pattern matches a permission without calling the backend, use the exported helper: ```typescript import { matchesPermissionPattern } from "@djpanda/convex-authz"; matchesPermissionPattern("documents:read", "documents:*"); // true matchesPermissionPattern("documents:read", "*:read"); // true matchesPermissionPattern("settings:read", "documents:*"); // false ``` The same wildcard behavior applies to all permission checks. ### Getting User Roles ```typescript const roles = await authz.getUserRoles(ctx, userId); // Returns: [{ role: "admin", scopeKey: "global" }, { role: "editor", scopeKey: "team:123", scope: { type: "team", id: "123" } }] ``` --- ## Bulk operations and offboarding For large-scale or enterprise workflows, the API supports bulk permission checks (up to 100 permissions) and role updates (up to 20 roles) in a single call. ### Bulk permission check (canAny) Check whether the user has **any** of the given permissions in one round-trip: ```typescript const allowed = await authz.canAny(ctx, userId, [ "documents:read", "documents:update", "documents:delete", ], scope); // true if the user has at least one of these permissions ``` ### Bulk role assign and revoke Assign or revoke multiple roles for one user in a **single transaction**: ```typescript // Assign multiple roles at once (max 20 per call) const { assigned, assignmentIds } = await authz.assignRoles(ctx, userId, [ { role: "admin" }, { role: "editor", scope: { type: "team", id: "team_1" } }, { role: "viewer", scope: { type: "org", id: "org_1" }, expiresAt: Date.now() + 86400000 }, ], actorId); // Revoke multiple roles at once (max 20 per call) const { revoked } = await authz.revokeRoles(ctx, userId, [ { role: "editor", scope: { type: "team", id: "team_1" } }, { role: "viewer" }, ], actorId); ``` ### Revoke all roles Revoke every role for a user (optionally only in a given scope): ```typescript const count = await authz.revokeAllRoles(ctx, userId); const countScoped = await authz.revokeAllRoles(ctx, userId, { type: "team", id: "team_1" }, actorId); ``` ### Full user offboarding Remove all roles, permission overrides, attributes, and optionally ReBAC relationships for a user in one call (optionally scoped). Also clears indexed `effectiveRoles`, `effectivePermissions`, and `effectiveRelationships` when present: ```typescript const result = await authz.offboardUser(ctx, userId, { scope: { type: "org", id: "org_1" }, // optional: only remove data in this scope actorId: "system", removeAttributes: true, // default true removeOverrides: true, // default true removeRelationships: true, // default true when no scope (full offboard) }); // result: { rolesRevoked, overridesRemoved, attributesRemoved, relationshipsRemoved, effectiveRolesRemoved, effectivePermissionsRemoved, effectiveRelationshipsRemoved } ``` When **scope is omitted**, the call performs a full deprovision: all roles, overrides, attributes, and all ReBAC relationships where the user is the subject are removed. When scope is provided, only data in that scope is removed and relationships are left unchanged. ### User deprovisioning (full wipe) For security incident response, enterprise offboarding, or single-button deactivation, use **deprovisionUser** to atomically wipe all roles, attributes, relationships, and permission overrides for a user (no scope, no options): ```typescript const result = await authz.deprovisionUser(ctx, userId, { actorId: "security-team", enableAudit: true, }); // result: { rolesRevoked, overridesRemoved, attributesRemoved, relationshipsRemoved, effectiveRolesRemoved, effectivePermissionsRemoved, effectiveRelationshipsRemoved } ``` Bulk arrays are limited per call: permissions in `canAny` up to **100 items**, roles in `assignRoles` / `revokeRoles` up to **20 items**. The client and component validate and throw a clear error if exceeded. --- ## ABAC (Attribute-Based Access Control) ### Setting User Attributes ```typescript await authz.setAttribute(ctx, userId, "department", "engineering"); await authz.setAttribute(ctx, userId, "clearanceLevel", 5); await authz.setAttribute(ctx, userId, "location", { country: "US", state: "CA" }); ``` ### Getting Attributes ```typescript const attributes = await authz.getUserAttributes(ctx, userId); // Returns: [{ key: "department", value: "engineering" }, { key: "clearanceLevel", value: 5 }] ``` ### Defining Policies The `condition` function may return either a `boolean` or a `Promise`, so you can use async logic (e.g. querying the database or calling external APIs). ```typescript import { definePolicies, evaluatePolicyCondition } from "@djpanda/convex-authz"; const policies = definePolicies({ "documents:update": { // User can update if they own the document (sync) condition: (ctx) => ctx.resource?.ownerId === ctx.subject.userId, message: "Only document owners can update", }, "reports:view": { // Only engineering department with clearance >= 3 (sync) condition: (ctx) => ctx.subject.attributes.department === "engineering" && (ctx.subject.attributes.clearanceLevel as number) >= 3, message: "Requires engineering department with clearance level 3+", }, "documents:delete": { // Async: e.g. check external service or fetch extra data condition: async (ctx) => { const doc = await getDocument(ctx.resource?.id); return doc != null && doc.ownerId === ctx.subject.userId; }, message: "Only document owners can delete", }, }); const authz = new Authz(components.authz, { permissions, roles, policies, tenantId: "my-app" }); ``` When you **evaluate** a policy (e.g. after RBAC allows), always **await** the condition so both sync and async policies work. Use `evaluatePolicyCondition` to normalize to a Promise: ```typescript const policy = policies["documents:update"]; if (policy) { const allowed = await evaluatePolicyCondition(policy.condition, policyCtx); if (!allowed) throw new Error(policy.message ?? "Permission denied"); } ``` ### Policy Context Policies receive a context object with: ```typescript interface PolicyContext { subject: { userId: string; roles: string[]; attributes: Record; }; resource?: { type: string; id: string; [key: string]: unknown; // Resource data }; action: string; // The permission being checked environment?: { timestamp: number; ip?: string; }; hasRole: (role: string) => boolean; hasAttribute: (key: string) => boolean; getAttribute: (key: string, defaultValue?: T) => T | undefined; } ``` **API note:** Existing sync conditions remain valid. There is no breaking change; only the return type is widened to allow `Promise` for async policies. --- ## ReBAC (Relationship-Based Access Control) ReBAC enables access control based on relationships between entities, perfect for hierarchical systems like CRMs, document sharing, and organizational structures. ### Relationship Model Relationships are stored as tuples: `(subject, relation, object)` ``` user:alice ──member──► team:sales team:sales ──owner──► account:acme account:acme ──parent──► deal:big_deal ``` ### Adding Relationships ```typescript // Use the Authz client — NOT direct component calls // User is member of team await authz.addRelation(ctx, { type: "user", id: "alice" }, "member", { type: "team", id: "sales" }); // Team owns account await authz.addRelation(ctx, { type: "team", id: "sales" }, "owner", { type: "account", id: "acme" }); ``` ### Checking Direct Relationships ```typescript // Use the Authz client — NOT direct component calls const isMember = await authz.hasRelation(ctx, { type: "user", id: "alice" }, "member", { type: "team", id: "sales" }); // Returns: true // To remove a relationship await authz.removeRelation(ctx, { type: "user", id: "alice" }, "member", { type: "team", id: "sales" }); ``` ### Relationship Traversal (Inherited Access) The real power of ReBAC is checking access through relationship chains: ```typescript // Define how permissions flow through relationships const traversalRules = { // A deal viewer is anyone who can view the parent account "deal:viewer": [ { through: "account", via: "parent", inherit: "viewer" } ], // An account viewer is any member of the owning team "account:viewer": [ { through: "team", via: "owner", inherit: "member" } ], }; // Graph traversal is available via the component query directly // Check: Can alice view big_deal? const result = await ctx.runQuery(components.authz.rebac.checkRelationWithTraversal, { subjectType: "user", subjectId: "alice", relation: "viewer", objectType: "deal", objectId: "big_deal", traversalRules, maxDepth: 5, }); // Returns: // { // allowed: true, // path: [ // "account:acme -[parent]-> deal:big_deal", // "team:sales -[owner]-> account:acme", // "user:alice -[member]-> team:sales" // ], // reason: "Access via relationship chain" // } ``` Traversal uses a **maxDepth** limit (default 5) and tracks visited `(objectType, objectId, relation)` nodes so that circular relationships do not cause infinite loops. ### CRM Example ```typescript // Setup CRM hierarchy using the Authz client const setupCRM = async (ctx) => { // Sales rep Alice is on sales team await authz.addRelation(ctx, { type: "user", id: "alice" }, "member", { type: "team", id: "sales" }); // Sales team owns Acme Corp account await authz.addRelation(ctx, { type: "team", id: "sales" }, "owner", { type: "account", id: "acme_corp" }); // Acme Corp has a big deal await authz.addRelation(ctx, { type: "account", id: "acme_corp" }, "parent", { type: "deal", id: "big_deal" }); // Now Alice can access the deal through the relationship chain! }; ``` --- ## O(1) Indexed Lookups For high-performance production use, the indexed system pre-computes permissions for instant lookups. ### Using the Indexed API ```typescript import { Authz } from "@djpanda/convex-authz"; import { components } from "./_generated/api"; const authz = new Authz(components.authz, { permissions, roles, tenantId: "my-app" }); // O(1) permission check - single index lookup const canEdit = await authz.can(ctx, userId, "documents:update"); // O(1) role check const isAdmin = await authz.hasRole(ctx, userId, "admin"); // O(1) relationship check const isMember = await authz.hasRelation(ctx, { type: "user", id: userId }, "member", { type: "team", id: "sales" }); ``` ### How It Works ``` Traditional (O(n)): Indexed (O(1)): ┌──────┐ ┌──────┐ │ User │ │ User │ └──┬───┘ └──┬───┘ │ │ ▼ ▼ ┌──────────┐ ┌─────────────────────────────┐ │ Get Roles│ ◄── Query │ Index Lookup: │ └──┬───────┘ │ effectivePermissions │ │ │ [userId, permission, scope] │ ▼ └─────────────────────────────┘ ┌───────────────┐ │ │ Expand Perms │ ◄── Loop ▼ └──┬────────────┘ true/false │ ▼ ┌──────────────┐ │ Check Each │ ◄── Loop │ Permission │ └──┬───────────┘ │ ▼ true/false ``` ### Trade-offs | Operation | Traditional | Indexed | | ---------------- | ---------------- | --------------------- | | Permission Check | O(roles × perms) | **O(1)** | | Role Assignment | O(1) | O(permissions) | | Permission Grant | O(1) | O(1) | | Memory Usage | Lower | Higher (denormalized) | **Use Indexed for production workloads with many permission checks.** --- ## Audit Logging All authorization changes are logged for compliance and debugging. ### Automatic Logging The following actions are automatically logged: - `role_assigned` - When a role is assigned - `role_revoked` - When a role is revoked - `permission_granted` - When a direct permission is granted - `permission_denied` - When a permission is explicitly denied - `attribute_set` - When a user attribute is set - `attribute_removed` - When a user attribute is removed - `permission_check` - (Optional) When permissions are checked ### Querying the Audit Log Without pagination options, `getAuditLog` returns a simple array (optional `limit`, default 100): ```typescript // Get all logs for a user const logs = await authz.getAuditLog(ctx, { userId: "user_123", limit: 50, }); // Get logs by action type const roleChanges = await authz.getAuditLog(ctx, { action: "role_assigned", limit: 100, }); ``` For scalable browsing, use **cursor-based pagination** by passing `numItems` (and optionally `cursor` for the next page). The return value is then `{ page, isDone, continueCursor }`: ```typescript // First page const result = await authz.getAuditLog(ctx, { numItems: 50 }); if (!Array.isArray(result)) { console.log(result.page); if (!result.isDone) { // Next page const next = await authz.getAuditLog(ctx, { numItems: 50, cursor: result.continueCursor, }); } } ``` ### Log Entry Structure ```typescript { _id: "...", timestamp: 1704672000000, actorId: "admin_user", // Who made the change action: "role_assigned", userId: "target_user", // Who was affected details: { role: "editor", scope: { type: "team", id: "team_123" }, }, } ``` --- ## Permission Overrides Grant or deny specific permissions that override role-based assignments. ### Granting Permissions ```typescript // Grant a permission directly (bypasses role checks) await authz.grantPermission(ctx, userId, "documents:delete", undefined, "Temporary access for migration"); // With scope await authz.grantPermission(ctx, userId, "documents:delete", { type: "team", id: "team_123" }); // With expiration await authz.grantPermission(ctx, userId, "documents:delete", undefined, "Temporary", Date.now() + 3600000); ``` ### Denying Permissions ```typescript // Deny a permission (even if user has it via role) await authz.denyPermission(ctx, userId, "documents:delete", undefined, "Access restricted"); ``` --- ## Schema Reference ### Tables | Table | Purpose | | ------------------------ | --------------------------------- | | `roleAssignments` | User role assignments | | `userAttributes` | User attributes for ABAC | | `permissionOverrides` | Direct permission grants/denials | | `relationships` | ReBAC relationship tuples | | `effectivePermissions` | Pre-computed permissions (O(1)) | | `effectiveRoles` | Pre-computed roles (O(1)) | | `effectiveRelationships` | Pre-computed relationships (O(1)) | | `auditLog` | Authorization audit trail | ### Indexes All tables have optimized indexes for common query patterns: ```typescript // roleAssignments .index("by_user", ["userId"]) .index("by_role", ["role"]) .index("by_user_and_role", ["userId", "role"]) // effectivePermissions (O(1) lookup) .index("by_user_permission_scope", ["userId", "permission", "scopeKey"]) // relationships .index("by_subject_relation_object", ["subjectType", "subjectId", "relation", "objectType", "objectId"]) ``` --- ## API Reference ### Authz Client ```typescript class Authz { // Permission checks can(ctx, userId, permission, scope?): Promise canAny(ctx, userId, permissions: string[], scope?): Promise // bulk: any of N permissions (max 100) require(ctx, userId, permission, scope?): Promise // Role management hasRole(ctx, userId, role, scope?): Promise assignRole(ctx, userId, role, scope?, expiresAt?, actorId?): Promise assignRoles(ctx, userId, roles: RoleAssignItem[], actorId?): Promise<{ assigned: number; assignmentIds: string[] }> // bulk, max 20 revokeRole(ctx, userId, role, scope?, actorId?): Promise revokeRoles(ctx, userId, roles: RoleScopeItem[], actorId?): Promise<{ revoked: number }> // bulk, max 20 revokeAllRoles(ctx, userId, scope?, actorId?): Promise getUserRoles(ctx, userId, scope?): Promise getUserPermissions(ctx, userId, scope?): Promise // Offboarding offboardUser(ctx, userId, options?: { scope?, actorId?, removeAttributes?, removeOverrides?, removeRelationships? }): Promise deprovisionUser(ctx, userId, options?: { actorId?, enableAudit? }): Promise // full wipe: roles, overrides, attributes, relationships // Attribute management setAttribute(ctx, userId, key, value, actorId?): Promise removeAttribute(ctx, userId, key, actorId?): Promise getUserAttributes(ctx, userId): Promise // Permission overrides grantPermission(ctx, userId, permission, scope?, reason?, expiresAt?, actorId?): Promise denyPermission(ctx, userId, permission, scope?, reason?, expiresAt?, actorId?): Promise // Audit getAuditLog(ctx, options?): Promise } ``` ### Argument validation All public methods on `Authz` validate their arguments before calling the component. Invalid inputs throw an `Error` with a clear message so you can fail fast and fix call sites. | Argument | Rule | Example error | | ------------------------------------- | ------------------------------------------------------------------------------------------ | --------------------------------------------------------------------- | | `userId` | Non-empty string, max 512 characters | `"userId must be a non-empty string"` | | `permission` | Must be `resource:action` (e.g. `documents:read`) | `"Invalid permission format: \"read\". Expected \"resource:action\""` | | `scope` | When provided, `type` and `id` must be non-empty strings | `"scope must have non-empty type when provided"` | | `role` | Non-empty string; must be one of the roles passed at construction | `"Unknown role: \"superadmin\""` | | `expiresAt` | When provided, must be a finite number (timestamp) | `"expiresAt must be a finite number"` | | Attribute `key` | Non-empty string | `"Attribute key must be a non-empty string"` | | `getAuditLog` `limit` | When provided, positive integer 1–1000 | `"limit must be a positive integer when provided"` | | `getAuditLog` `numItems` | When provided (pagination), positive integer 1–1000 | same as `limit` | | Relation args | `subjectType`, `subjectId`, `relation`, `objectType`, `objectId` must be non-empty strings | `"subjectType must be a non-empty string"` | | `canAny` `permissions` | Non-empty array, each element valid `resource:action`, length ≤ 100 | `"permissions must not exceed 100 items"` | | `assignRoles` / `revokeRoles` `roles` | Non-empty array, each role valid, length ≤ 20 | `"roles must not exceed 20 items"` | Optional parameters are only validated when present (e.g. omitting `scope` is valid; passing `scope: { type: "", id: "x" }` throws). --- ## Inspired by Google Zanzibar This component implements concepts from [Google Zanzibar](https://research.google/pubs/pub48190/), Google's global authorization system that powers Google Drive, YouTube, Cloud, and more. ### Zanzibar Concepts Implemented | Zanzibar Concept | Our Implementation | Description | | ---------------------- | ---------------------------- | ---------------------------------- | | **Relation Tuples** | `relationships` table | `(user:alice, member, team:sales)` | | **Usersets** | Traversal rules | Groups defined by relationships | | **Check API** | `checkPermissionFast` | O(1) "can user X do Y on Z?" | | **Expand API** | `checkRelationWithTraversal` | Find all paths granting access | | **Read API** | `getSubjectRelations` | List all relationships | | **Watch API** | Convex reactivity | Real-time permission updates | | **Computed Relations** | `effectivePermissions` | Pre-computed for O(1) lookup | ### How Zanzibar Works ``` ┌─────────────────────────────────────────────────────────────────────────────┐ │ Google Zanzibar Model │ ├─────────────────────────────────────────────────────────────────────────────┤ │ │ │ Relation Tuples (stored): │ │ ┌────────────────────────────────────────────────────────────────────┐ │ │ │ (user:alice, member, team:sales) │ │ │ │ (team:sales, owner, account:acme) │ │ │ │ (account:acme, parent, deal:big_deal) │ │ │ └────────────────────────────────────────────────────────────────────┘ │ │ │ │ Authorization Model (defines inheritance): │ │ ┌────────────────────────────────────────────────────────────────────┐ │ │ │ type deal │ │ │ │ relations │ │ │ │ define parent: [account] │ │ │ │ define viewer: viewer from parent ← Computed relation │ │ │ └────────────────────────────────────────────────────────────────────┘ │ │ │ │ Check: "Can alice view deal:big_deal?" │ │ ┌────────────────────────────────────────────────────────────────────┐ │ │ │ 1. deal:big_deal.viewer = viewer from parent │ │ │ │ 2. parent = account:acme │ │ │ │ 3. account:acme.viewer = member from owner │ │ │ │ 4. owner = team:sales │ │ │ │ 5. team:sales.member includes user:alice ✓ │ │ │ │ → ALLOWED │ │ │ └────────────────────────────────────────────────────────────────────┘ │ │ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` ### Key Zanzibar Benefits We Provide 1. **Consistency at Scale** - Pre-computed permissions ensure fast, consistent checks - No permission drift between reads 2. **Flexible Permission Model** - Combine RBAC, ABAC, and ReBAC as needed - Support complex hierarchies (org → team → project → resource) 3. **Auditability** - Full audit log of all permission changes - Path tracing shows WHY access was granted 4. **Real-time Updates** - Convex reactivity means UI updates instantly when permissions change - No polling required (better than Zanzibar!) --- ## Comparison with Other Solutions | Feature | @djpanda/convex-authz | OpenFGA | Oso | Cerbos | | ------------- | --------------------- | ---------- | ------- | ------- | | RBAC | ✅ | ✅ | ✅ | ✅ | | ABAC | ✅ | ⚠️ Limited | ✅ | ✅ | | ReBAC | ✅ | ✅ Native | ✅ | ⚠️ | | O(1) Lookups | ✅ | ✅ | ✅ | ✅ | | Convex Native | ✅ | ❌ | ❌ | ❌ | | Type Safety | ✅ TypeScript | DSL | Polar | YAML | | Real-time | ✅ Convex queries | Polling | Polling | Polling | | Self-hosted | ✅ | ✅ | ✅ | ✅ | --- ## Testing ### Running Package Tests ```bash cd packages/authz npm test ``` ### Using with convex-test ```typescript import { convexTest } from "convex-test"; import { describe, expect, it } from "vitest"; import schema from "./component/schema.js"; import { api } from "./component/_generated/api.js"; describe("authorization", () => { it("should assign and check roles", async () => { const t = convexTest(schema, modules); await t.mutation(api.mutations.assignRole, { userId: "user_123", role: "admin", }); const hasRole = await t.query(api.queries.hasRole, { userId: "user_123", role: "admin", }); expect(hasRole).toBe(true); }); }); ``` --- ## Multi-Tenant Data Isolation Every table in the authz component includes a required `tenantId` field as the leading column in every database index. This provides database-level data isolation between tenants — queries for one tenant can never return data from another. ### tenantId vs scope | | `tenantId` | `scope` | | --------------- | ----------------------------- | ------------------------------------- | | **Purpose** | Data isolation boundary | Resource-level grouping | | **Enforcement** | Database-level (index prefix) | Application-level (query filter) | | **Required** | Always | Optional | | **Example** | `"acme-corp"` | `{ type: "project", id: "proj-123" }` | - **tenantId** answers: "whose data is this?" — the organization/customer boundary - **scope** answers: "within this tenant, what resource does this apply to?" — e.g. admin of a specific project ### Configuration ```typescript // Single-tenant apps — pass any constant string const authz = new Authz(components.authz, { permissions, roles, tenantId: "my-app", }); // Multi-tenant apps — pass the current organization/tenant ID const authz = new Authz(components.authz, { permissions, roles, tenantId: currentOrgId, }); ``` ### Cross-tenant operations For rare admin operations that need to access a different tenant's data, use the `withTenant()` method: ```typescript // Returns a new Authz instance scoped to a different tenant const otherTenant = authz.withTenant("other-org-id"); await otherTenant.getUserRoles(ctx, userId); ``` ### Compliance The `tenantId`-first index design satisfies SOC2 and HIPAA data isolation requirements: - All queries are partitioned by tenant at the database index level - Cross-tenant data access is structurally impossible through the standard API - `tenantId` is required in the constructor — it cannot be accidentally omitted --- ## Best Practices ### 1. Use Scoped Roles for Multi-tenancy ```typescript // Don't: Global admin await authz.assignRole(ctx, userId, "admin"); // Do: Scoped admin await authz.assignRole(ctx, userId, "admin", { type: "org", id: orgId }); ``` ### 2. Use the Authz Client for Production ```typescript // Authz uses O(1) indexed lookups by default — no separate class needed const authz = new Authz(components.authz, { permissions, roles, tenantId: "my-app" }); ``` ### 3. Use ReBAC for Complex Hierarchies ```typescript // CRM, document sharing, org charts → ReBAC // Simple role assignments → RBAC ``` ### 4. Set Expiration for Temporary Access ```typescript await authz.assignRole(ctx, userId, "contractor", undefined, Date.now() + 30 * 24 * 60 * 60 * 1000 // 30 days ); ``` ### 5. Always Use Audit Logging The audit log is invaluable for: - Compliance (SOC2, GDPR) - Debugging access issues - Security incident investigation ### 6. Cleanup of Expired Data (Scheduled via Component) Expired role assignments and permission overrides (and their indexed rows) are purged by a **scheduled cleanup job** that you enable once—no need to add `convex/crons.ts` yourself. The component embeds [@convex-dev/crons](https://www.convex.dev/components/crons); run this **once** after installing the component to register the daily job: ```bash npx convex run authz/cronSetup:ensureCleanupCronRegistered ``` Or from an init script that runs on deploy (e.g. `convex/init.ts` invoked via `convex dev --run init`): ```typescript await ctx.runMutation(components.authz.cronSetup.ensureCleanupCronRegistered, {}); ``` The job runs every 24 hours and cleans `roleAssignments`, `permissionOverrides`, `effectiveRoles`, and `effectivePermissions`. Optional: you can instead define the cleanup in your app's `convex/crons.ts` or run `components.authz.mutations.runScheduledCleanup` manually. ### 6.1. Audit log retention To avoid unbounded growth of the audit log (compliance and cost), the same cron registration also schedules a **daily audit retention job**. Configure it with Convex environment variables (Dashboard or CLI): | Variable | Description | | ----------------------------- | ------------------------------------------------------------------------------------------------------------------- | | `AUDIT_RETENTION_DAYS` | Delete entries older than this many days (e.g. `90`). Omit or `0` = do not prune by age. | | `AUDIT_RETENTION_MAX_ENTRIES` | Cap total entries by deleting oldest until count ≤ this value (e.g. `100000`). Omit or `0` = do not prune by count. | Set at least one to enable retention. The job runs every 24 hours (same `ensureCleanupCronRegistered` flow). You can also run `components.authz.mutations.runAuditRetentionCleanup` manually with optional args `{ maxAgeDays?, maxEntries? }` to override env for that run. ### 7. Use Authz as a Global Singleton Authz is a **global component** — install it once and share a single client instance across your entire app. Do not create multiple `Authz` instances per app. ``` convex/ convex.config.ts ← app.use(authz) — registered once authz.ts ← definePermissions, defineRoles, export authz client documents.ts ← import { authz } from "./authz" billing.ts ← import { authz } from "./authz" settings.ts ← import { authz } from "./authz" ``` ```typescript // convex/authz.ts — single source of truth import { Authz, definePermissions, defineRoles } from "@djpanda/convex-authz"; import { components } from "./_generated/api"; const permissions = definePermissions({ documents: { create: true, read: true, update: true, delete: true }, billing: { view: true, manage: true }, settings: { view: true, manage: true }, }); const roles = defineRoles(permissions, { admin: { documents: ["create", "read", "update", "delete"], billing: ["view", "manage"], settings: ["view", "manage"], }, viewer: { documents: ["read"], settings: ["view"], }, }); // Export the single authz client — import this everywhere export const authz = new Authz(components.authz, { permissions, roles, tenantId: "my-app" }); ``` ```typescript // convex/documents.ts — uses the shared client import { mutation } from "./_generated/server"; import { authz } from "./authz"; export const deleteDocument = mutation({ args: { docId: v.id("documents") }, handler: async (ctx, args) => { await authz.require(ctx, userId, "documents:delete"); // ... }, }); ``` ### 7. Organize Permissions by Domain In larger apps, split permission and role definitions by domain and merge them into a single authz client using `definePermissions` and `defineRoles`: ```typescript // convex/permissions/documents.ts export const documentPermissions = { documents: { create: true, read: true, update: true, delete: true }, }; export const documentRoles = { editor: { documents: ["create", "read", "update"] as const }, viewer: { documents: ["read"] as const }, }; // convex/permissions/billing.ts export const billingPermissions = { billing: { view: true, manage: true }, }; export const billingRoles = { billing_admin: { billing: ["view", "manage"] as const }, }; ``` ```typescript // convex/authz.ts — merge all domains import { Authz, definePermissions, defineRoles } from "@djpanda/convex-authz"; import { components } from "./_generated/api"; import { documentPermissions, documentRoles } from "./permissions/documents"; import { billingPermissions, billingRoles } from "./permissions/billing"; const permissions = definePermissions(documentPermissions, billingPermissions); const roles = defineRoles(permissions, documentRoles, billingRoles); export const authz = new Authz(components.authz, { permissions, roles, tenantId: "my-app" }); ``` This keeps each domain self-contained while producing a single, type-safe authz client. ### 8. Integrating with Other Convex Components When other Convex components (e.g., `@djpanda/convex-tenants`) need authorization, they share the **same global authz instance**. The pattern: 1. Register both components independently in `convex.config.ts` 2. The other component exports its required permissions and roles 3. Merge them with your app's own definitions 4. Pass the authz client to the other component's API factory ```mermaid graph LR subgraph app ["Your App (convex.config.ts)"] AuthzComp["authz component"] TenantsComp["tenants component"] end subgraph authzSetup ["convex/authz.ts"] AppPerms["App permissions"] TenantPerms["Tenant permissions"] Merge["definePermissions + defineRoles"] Client["authz client (singleton)"] AppPerms --> Merge TenantPerms --> Merge Merge --> Client end Client -->|"import { authz }"| Docs["convex/documents.ts"] Client -->|"import { authz }"| Billing["convex/billing.ts"] Client -->|"passed to makeTenantsAPI"| TenantsAPI["convex/tenants.ts"] ``` ```typescript // convex/convex.config.ts — register both components import { defineApp } from "convex/server"; import authz from "@djpanda/convex-authz/convex.config"; import tenants from "@djpanda/convex-tenants/convex.config"; const app = defineApp(); app.use(authz); app.use(tenants); export default app; ``` ```typescript // convex/authz.ts — merge app + component permissions import { Authz, definePermissions, defineRoles } from "@djpanda/convex-authz"; import { TENANTS_PERMISSIONS, TENANTS_ROLES } from "@djpanda/convex-tenants"; import { components } from "./_generated/api"; // Your app's own permissions const appPermissions = { documents: { create: true, read: true, update: true, delete: true }, }; const appRoles = { editor: { documents: ["create", "read", "update"] as const }, }; // Merge with tenant component's permissions const permissions = definePermissions(appPermissions, TENANTS_PERMISSIONS); const roles = defineRoles(permissions, appRoles, TENANTS_ROLES); export const authz = new Authz(components.authz, { permissions, roles, tenantId: "my-app" }); ``` ```typescript // convex/tenants.ts — pass the shared authz client import { makeTenantsAPI } from "@djpanda/convex-tenants"; import { components } from "./_generated/api"; import { authz } from "./authz"; export const { createOrg, inviteMember, removeMember, // ... } = makeTenantsAPI(components.tenants, { authz, creatorRole: "owner", auth: async (ctx) => { // return the current user ID }, }); ``` This way every part of your app — your own functions and third-party components — shares a single, consistent authorization layer. --- ## Using with AI Coding Agents `@djpanda/convex-authz` is available as an [agent skill](https://vercel.com/docs/agent-resources/skills) that gives AI coding agents deep knowledge of this library's API, patterns, and best practices. ### Install the skill ```bash npx skills add dbjpanda/convex-authz ``` This works with **18+ AI agents** including Claude Code, Cursor, GitHub Copilot, Cline, Windsurf, and others. Once installed, your agent will automatically know how to: - Set up the component and define permissions/roles - Use RBAC, ABAC, and ReBAC patterns correctly - Write O(1) permission checks - Configure multi-tenant isolation - Follow Convex conventions ### Browse more skills ```bash npx skills find convex ``` Or visit [skills.sh](https://skills.sh) to discover community skills. --- ## Development ```bash # Install dependencies npm install # Run development mode npm run dev # Run tests npm test # Build for production npm run build # Type check npm run typecheck ``` --- ## File Structure ``` packages/authz/ ├── package.json # Package configuration ├── README.md # This documentation ├── src/ │ ├── client/ │ │ ├── index.ts # Main exports (Authz, helpers) │ │ └── index.test.ts # Client tests │ ├── component/ │ │ ├── convex.config.ts # Component registration │ │ ├── schema.ts # Database tables and indexes │ │ ├── helpers.ts # Shared utilities │ │ ├── queries.ts # Query functions │ │ ├── mutations.ts # Mutation functions │ │ ├── rebac.ts # ReBAC relationship functions │ │ ├── indexed.ts # O(1) indexed functions │ │ ├── authz.test.ts # RBAC/ABAC tests │ │ ├── rebac.test.ts # ReBAC tests │ │ ├── indexed.test.ts # O(1) indexed tests │ │ └── _generated/ # Auto-generated types │ └── test.ts # Test helpers └── example/ # Example app ``` --- ## License MIT --- ## Contributing Contributions are welcome! Please read our [CONTRIBUTING.md](CONTRIBUTING.md) before submitting a PR.