diff --git a/src/app.ts b/src/app.ts
index 32f1d92..21bfc92 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -1,11 +1,18 @@
 import Fastify from 'fastify'
-import prismaPlugin from './plugins/prisma'
+import cookie from '@fastify/cookie'
+import prismaPlugin from './plugins/prisma.js'
+import mailerPlugin from './plugins/mailer.js'
+import authRoutes from './routes/auth.js'
 import userRoutes from './routes/users.js'
 
 export default function buildApp() {
   const app = Fastify({ logger: true })
 
+  app.register(cookie)
   app.register(prismaPlugin)
+  app.register(mailerPlugin)
+  
+  app.register(authRoutes, { prefix: '/api' })
   app.register(userRoutes, { prefix: '/api' })
 
   app.get('/health', async () => ({ status: 'ok' }))
diff --git a/src/plugins/mailer.ts b/src/plugins/mailer.ts
new file mode 100644
index 0000000..d0388fb
--- /dev/null
+++ b/src/plugins/mailer.ts
@@ -0,0 +1,22 @@
+import fp from 'fastify-plugin'
+import { FastifyInstance } from 'fastify'
+import nodemailer, { Transporter } from 'nodemailer'
+
+declare module 'fastify' {
+  interface FastifyInstance {
+    mailer: Transporter
+  }
+}
+
+export default fp(async (fastify: FastifyInstance) => {
+  const transporter = nodemailer.createTransport({
+    host: process.env.SMTP_HOST,
+    port: Number(process.env.SMTP_PORT),
+    auth: {
+      user: process.env.SMTP_USER,
+      pass: process.env.SMTP_PASS,
+    },
+  })
+
+  fastify.decorate('mailer', transporter)
+})
\ No newline at end of file
diff --git a/src/routes/auth.ts b/src/routes/auth.ts
new file mode 100644
index 0000000..2b2b827
--- /dev/null
+++ b/src/routes/auth.ts
@@ -0,0 +1,41 @@
+import { FastifyInstance } from 'fastify'
+import { ZodError } from 'zod'
+import { RegisterSchema } from '../schemas/auth.schema.js'
+import { registerUser } from '../services/auth.service.js'
+
+export default async function authRoutes(fastify: FastifyInstance) {
+  fastify.post('/auth/register', async (request, reply) => {
+    // Validation Zod
+    let body
+    try {
+      body = RegisterSchema.parse(request.body)
+    } catch (err) {
+      if (err instanceof ZodError) {
+        return reply.status(400).send({ error: 'VALIDATION_ERROR', details: err.errors })
+      }
+      throw err
+    }
+
+    // Register
+    try {
+      const { user, authToken } = await registerUser(
+        fastify.prisma,
+        fastify.mailer,
+        body
+      )
+
+      reply.setCookie('authToken', authToken, {
+        httpOnly: true,
+        sameSite: 'strict',
+        maxAge: 60 * 60 * 24 * 7, // 7 jours en secondes
+      })
+
+      return reply.status(201).send({ user })
+    } catch (err: any) {
+      if (err.message === 'EMAIL_TAKEN') {
+        return reply.status(409).send({ error: 'EMAIL_TAKEN' })
+      }
+      throw err
+    }
+  })
+}
\ No newline at end of file
diff --git a/src/schemas/auth.schema.ts b/src/schemas/auth.schema.ts
new file mode 100644
index 0000000..47936a8
--- /dev/null
+++ b/src/schemas/auth.schema.ts
@@ -0,0 +1,9 @@
+import { z } from 'zod'
+
+export const RegisterSchema = z.object({
+  email: z.string().email(),
+  password: z.string().min(8),
+  displayName: z.string().min(2).max(50),
+})
+
+export type RegisterInput = z.infer<typeof RegisterSchema>
\ No newline at end of file
diff --git a/src/services/auth.service.ts b/src/services/auth.service.ts
new file mode 100644
index 0000000..d02bd02
--- /dev/null
+++ b/src/services/auth.service.ts
@@ -0,0 +1,70 @@
+import argon2 from 'argon2'
+import crypto from 'crypto'
+import { PrismaClient } from '../generated/prisma/client.js'
+import { Transporter } from 'nodemailer'
+import { RegisterInput } from '../schemas/auth.schema.js'
+import { generateToken, generateAuthTokenExpiry, generateActionTokenExpiry } from './token.service.js'
+import { sendConfirmationMail } from './mail.service.js'
+
+export async function registerUser(
+  prisma: PrismaClient,
+  mailer: Transporter,
+  input: RegisterInput
+) {
+  // 1. Vérif email unique
+  const existing = await prisma.user.findUnique({
+    where: { email: input.email },
+  })
+  if (existing) {
+    throw new Error('EMAIL_TAKEN')
+  }
+
+  // 2. Hash du mot de passe
+  const passwordHash = await argon2.hash(input.password)
+
+  // 3. Création de l'user
+  const user = await prisma.user.create({
+    data: {
+      id: crypto.randomUUID(),
+      email: input.email,
+      passwordHash,
+      displayName: input.displayName,
+      avatar: '',
+    },
+    select: {
+      id: true,
+      email: true,
+      displayName: true,
+      isConfirmed: true,
+      createdAt: true,
+    },
+  })
+
+  // 4. ActionToken pour confirmation mail
+  const confirmToken = generateToken()
+  await prisma.actionToken.create({
+    data: {
+      id: crypto.randomUUID(),
+      userId: user.id,
+      token: confirmToken,
+      type: 'email-confirm',
+      expiresAt: generateActionTokenExpiry(1440), // 24h
+    },
+  })
+
+  // 5. Envoi du mail
+  await sendConfirmationMail(mailer, user.email, confirmToken)
+
+  // 6. AuthToken pour la persistance
+  const authToken = generateToken()
+  await prisma.authToken.create({
+    data: {
+      id: crypto.randomUUID(),
+      userId: user.id,
+      token: authToken,
+      expiresAt: generateAuthTokenExpiry(),
+    },
+  })
+
+  return { user, authToken }
+}
\ No newline at end of file
diff --git a/src/services/mail.service.ts b/src/services/mail.service.ts
new file mode 100644
index 0000000..999edd9
--- /dev/null
+++ b/src/services/mail.service.ts
@@ -0,0 +1,20 @@
+import { Transporter } from 'nodemailer'
+
+export async function sendConfirmationMail(
+  mailer: Transporter,
+  email: string,
+  token: string
+): Promise<void> {
+  const url = `${process.env.APP_URL}/auth/confirm-email?token=${token}`
+
+  await mailer.sendMail({
+    from: process.env.MAIL_FROM,
+    to: email,
+    subject: 'Confirmez votre adresse mail',
+    html: `
+      <p>Merci de vous être inscrit !</p>
+      <p>Cliquez sur ce lien pour confirmer votre adresse mail (valable 24h) :</p>
+      <a href="${url}">${url}</a>
+    `,
+  })
+}
\ No newline at end of file
diff --git a/src/services/token.service.ts b/src/services/token.service.ts
new file mode 100644
index 0000000..c2c5034
--- /dev/null
+++ b/src/services/token.service.ts
@@ -0,0 +1,17 @@
+import crypto from 'crypto'
+
+export function generateToken(length = 32): string {
+  return crypto.randomBytes(length).toString('hex')
+}
+
+export function generateAuthTokenExpiry(): Date {
+  const date = new Date()
+  date.setDate(date.getDate() + 7)
+  return date
+}
+
+export function generateActionTokenExpiry(minutes = 1440): Date {
+  const date = new Date()
+  date.setMinutes(date.getMinutes() + minutes)
+  return date
+}
\ No newline at end of file