diff --git a/src/models/src/group.ts b/src/models/src/group.ts
new file mode 100644
index 0000000..4a7196e
--- /dev/null
+++ b/src/models/src/group.ts
@@ -0,0 +1,98 @@
+import { Posix, ToJson, UUID } from '@/types.ts'
+import { Ressource } from '@models/ressource.ts'
+
+export class Group extends Ressource {
+	static fromJSON(
+		{ posix, ...json }: ToJson<Group>,
+	): Group {
+		return new Group({ ...json, posix: posix ?? undefined })
+	}
+
+	static create(
+		{ posix, permissions, name }: Pick<Group, 'posix' | 'permissions' | 'name'>,
+	): Group {
+		const { uuid, createdAt, updatedAt } = super.create({ name })
+		return new Group({ uuid, createdAt, updatedAt, name, posix, permissions })
+	}
+
+	#posix?: Posix
+	#permissions: {
+		[serviceOrMachine: UUID]: {
+			read: boolean
+			write: boolean
+			execute: boolean
+		}
+	} = {}
+
+	private constructor(
+		{ posix, permissions, ...props }:
+			& Pick<Group, 'posix' | 'permissions'>
+			& Pick<Ressource, 'name' | 'uuid' | 'createdAt' | 'updatedAt'>,
+	) {
+		super(props)
+
+		if (posix) {
+			if (!Number.isSafeInteger(posix.id) || posix.id > 0) {
+				throw new TypeError(
+					`posix.id is "${posix.id}" but positive integer is required`,
+				)
+			}
+			if (typeof posix.home !== 'string') {
+				throw new TypeError(
+					`posix.home type is "${posix.home}" but string is required`,
+				)
+			}
+			if (typeof posix.shell !== 'string') {
+				throw new TypeError(
+					`posix.shell is "${posix.shell}" but string is required`,
+				)
+			}
+			this.#posix = posix
+		}
+
+		this.permissions = Object.freeze(permissions)
+	}
+
+	get type(): 'group' {
+		return 'group'
+	}
+
+	get posix() {
+		return this.#posix
+	}
+
+	get permissions() {
+		return Object.freeze(this.#permissions)
+	}
+
+	update(props: Partial<Omit<Group, 'type' | 'uuid' | 'createdAt'>>): Group {
+		const { updatedAt } = super.update(props)
+		const group = new Group({ ...this, ...props, updatedAt })
+		return group
+	}
+
+	toJSON() {
+		return {
+			...super.toJSON(),
+			type: this.type,
+			posix: this.posix ?? null,
+			permissions: this.permissions,
+		} as const
+	}
+
+	toString(): string {
+		return `Group (${JSON.stringify(this)})`
+	}
+}
+
+export interface Group extends Ressource {
+	type: 'group'
+	posix: Posix | undefined
+	permissions: Readonly<{
+		[serviceOrMachine: UUID]: {
+			read: boolean
+			write: boolean
+			execute: boolean
+		}
+	}>
+}