diff --git a/app/api/upload/check/route.ts b/app/api/upload/check/route.ts
new file mode 100644
index 0000000..2981911
--- /dev/null
+++ b/app/api/upload/check/route.ts
@@ -0,0 +1,50 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { validateUploadSecret } from '@/lib/auth'
+import { sanitizeFilename } from '@/lib/sanitize'
+import { VALID_DESTINATIONS } from '@/lib/constants'
+import { getRemoteFolder } from '@/lib/github'
+
+export const runtime = 'nodejs'
+export const dynamic = 'force-dynamic'
+
+/**
+ * GET /api/upload/check?destination=...&folderName=...
+ * Check if a folder already exists on the remote repo and return file SHAs.
+ */
+export async function GET(req: NextRequest) {
+  const authError = validateUploadSecret(req)
+  if (authError) return authError
+
+  const { searchParams } = new URL(req.url)
+  const destination = searchParams.get('destination')?.trim()
+  const folderName = searchParams.get('folderName')?.trim()
+
+  if (!destination || !folderName) {
+    return NextResponse.json({ success: false, error: 'Parametres manquants' }, { status: 400 })
+  }
+
+  if (!VALID_DESTINATIONS.has(destination as never)) {
+    return NextResponse.json({ success: false, error: 'Destination invalide' }, { status: 400 })
+  }
+
+  const safeFolderName = sanitizeFilename(folderName).replace(/[^a-zA-Z0-9-_]/g, '-')
+  const folderPath = `public/models/${destination}/${safeFolderName}`
+
+  try {
+    const { exists, files } = await getRemoteFolder(folderPath)
+
+    if (exists) {
+      return NextResponse.json({
+        success: true,
+        exists: true,
+        path: folderPath,
+        files,
+      })
+    }
+
+    return NextResponse.json({ success: true, exists: false })
+  } catch (err) {
+    const message = err instanceof Error ? err.message : 'Erreur inconnue'
+    return NextResponse.json({ success: false, error: message }, { status: 500 })
+  }
+}
diff --git a/app/api/upload/drive/route.ts b/app/api/upload/drive/route.ts
new file mode 100644
index 0000000..97676ba
--- /dev/null
+++ b/app/api/upload/drive/route.ts
@@ -0,0 +1,26 @@
+import { NextResponse } from 'next/server'
+
+export const runtime = 'nodejs'
+export const dynamic = 'force-dynamic'
+
+// ---------------------------------------------------------------------------
+// TODO: POST /api/upload/drive
+//
+// Upload files and push them to Google Drive.
+// This route will share the same auth (lib/auth.ts), parsing (lib/parse-upload.ts),
+// and Blender compression (lib/blender.ts) as the git route.
+//
+// Implementation steps:
+// 1. Add `googleapis` package: npm install googleapis
+// 2. Add env vars: GOOGLE_DRIVE_FOLDER_ID, GOOGLE_SERVICE_ACCOUNT_KEY (JSON)
+// 3. Authenticate with Google Drive API using service account
+// 4. Upload files to the target folder (create subfolders as needed)
+// 5. Return the Drive folder URL
+// ---------------------------------------------------------------------------
+
+export async function POST() {
+  return NextResponse.json(
+    { success: false, error: 'Google Drive upload not implemented yet' },
+    { status: 501 },
+  )
+}
diff --git a/app/api/upload/git/route.ts b/app/api/upload/git/route.ts
new file mode 100644
index 0000000..221d2ff
--- /dev/null
+++ b/app/api/upload/git/route.ts
@@ -0,0 +1,169 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { join } from 'path'
+import { mkdir, writeFile, readFile, unlink, rm } from 'fs/promises'
+import { existsSync } from 'fs'
+import { validateUploadSecret } from '@/lib/auth'
+import { parseMultiUpload } from '@/lib/parse-upload'
+import { compressWithBlender } from '@/lib/blender'
+import { computeGitBlobSha, getRemoteFolder, pushAllToGitHub } from '@/lib/github'
+import { buildCommitMessage } from '@/lib/commit-message'
+import { TMP_DIR } from '@/lib/constants'
+import type { FileChange } from '@/lib/types'
+
+export const runtime = 'nodejs'
+export const dynamic = 'force-dynamic'
+
+/**
+ * POST /api/upload/git
+ * Upload files, compress with Blender, and push to GitHub via Octokit.
+ */
+export async function POST(req: NextRequest) {
+  // --- Auth ---
+  const authError = validateUploadSecret(req)
+  if (authError) return authError
+
+  // --- Parse all files ---
+  let folderName: string
+  let destination: string
+  let parsedFiles: Awaited<ReturnType<typeof parseMultiUpload>>['files']
+
+  try {
+    const parsed = await parseMultiUpload(req)
+    folderName = parsed.folderName
+    destination = parsed.destination
+    parsedFiles = parsed.files
+  } catch (err) {
+    const message = err instanceof Error ? err.message : 'Erreur inconnue'
+    return NextResponse.json({ success: false, error: message }, { status: 400 })
+  }
+
+  // --- Process files (compress model if possible) ---
+  const filesToPush: { path: string; contentBase64: string }[] = []
+  let modelFilename = ''
+  let compressed = false
+  let compressionError: string | undefined
+  const textureNames: string[] = []
+
+  for (const pf of parsedFiles) {
+    let content = pf.buffer
+
+    if (pf.isModel) {
+      modelFilename = pf.filename
+
+      // Write to /tmp for Blender compression
+      const tmpFolder = join(TMP_DIR, folderName)
+      await mkdir(tmpFolder, { recursive: true })
+      const tmpFilePath = join(tmpFolder, pf.filename)
+      await writeFile(tmpFilePath, pf.buffer)
+
+      const stem = pf.filename.replace(/\.[^.]+$/, '')
+      const compressedPath = join(tmpFolder, `${stem}_compressed.glb`)
+
+      try {
+        const result = await compressWithBlender(tmpFilePath, compressedPath)
+
+        if (result.success && existsSync(compressedPath)) {
+          content = await readFile(compressedPath)
+          compressed = true
+          await unlink(compressedPath).catch(() => {})
+        } else {
+          compressionError = result.error
+        }
+      } finally {
+        // Always cleanup temp files
+        await unlink(tmpFilePath).catch(() => {})
+        await rm(tmpFolder, { recursive: true, force: true }).catch(() => {})
+      }
+    } else {
+      textureNames.push(pf.filename)
+    }
+
+    filesToPush.push({
+      path: `public/models/${destination}/${folderName}/${pf.filename}`,
+      contentBase64: content.toString('base64'),
+    })
+  }
+
+  // --- Detect existing files and compare SHA to classify changes ---
+  const folderPath = `public/models/${destination}/${folderName}`
+  let remoteFileMap: Map<string, string>
+
+  try {
+    const remote = await getRemoteFolder(folderPath)
+    remoteFileMap = new Map(remote.files.map((f) => [f.name.toLowerCase(), f.sha]))
+  } catch {
+    remoteFileMap = new Map()
+  }
+
+  const isReplace = remoteFileMap.size > 0
+
+  // Classify each file: changed, new, or unchanged
+  const fileChanges = new Map<string, FileChange>()
+  const changedFilesToPush: { path: string; contentBase64: string }[] = []
+
+  for (const f of filesToPush) {
+    const filename = f.path.split('/').pop() ?? ''
+    const localSha = computeGitBlobSha(Buffer.from(f.contentBase64, 'base64'))
+    const remoteSha = remoteFileMap.get(filename.toLowerCase())
+
+    if (!remoteSha) {
+      fileChanges.set(filename.toLowerCase(), 'new')
+      changedFilesToPush.push(f)
+    } else if (remoteSha !== localSha) {
+      fileChanges.set(filename.toLowerCase(), 'changed')
+      changedFilesToPush.push(f)
+    } else {
+      fileChanges.set(filename.toLowerCase(), 'unchanged')
+    }
+  }
+
+  // Files on remote not in the new upload → deleted (orphans)
+  const newFileNames = new Set(filesToPush.map((f) => (f.path.split('/').pop() ?? '').toLowerCase()))
+  const deletedFileNames: string[] = []
+  const deletePaths: string[] = []
+  for (const [name] of remoteFileMap) {
+    if (!newFileNames.has(name)) {
+      deletedFileNames.push(name)
+      deletePaths.push(`${folderPath}/${name}`)
+    }
+  }
+
+  // If nothing changed, don't create an empty commit
+  if (changedFilesToPush.length === 0 && deletePaths.length === 0) {
+    return NextResponse.json({
+      success: true,
+      folderName,
+      filesCount: 0,
+      compressed,
+      compressionError: compressionError || undefined,
+      message: 'Aucun fichier modifie — rien a envoyer.',
+    })
+  }
+
+  // --- Build commit message ---
+  const commitMessage = buildCommitMessage(
+    folderName, destination, modelFilename, textureNames,
+    compressed, isReplace, fileChanges, deletedFileNames,
+  )
+
+  // --- Push all in one commit ---
+  try {
+    const { commitUrl } = await pushAllToGitHub(changedFilesToPush, deletePaths, commitMessage)
+
+    return NextResponse.json({
+      success: true,
+      folderName,
+      filesCount: changedFilesToPush.length,
+      compressed,
+      compressionError: compressionError || undefined,
+      message: `${changedFilesToPush.length} fichier(s) modifie(s) envoye(s) sur GitHub en un seul commit.`,
+      commitUrl,
+    })
+  } catch (err) {
+    const message = err instanceof Error ? err.message : 'Erreur GitHub inconnue'
+    return NextResponse.json(
+      { success: false, error: `Push GitHub echoue: ${message}` },
+      { status: 500 },
+    )
+  }
+}
diff --git a/app/api/upload/route.ts b/app/api/upload/route.ts
deleted file mode 100644
index 13a2475..0000000
--- a/app/api/upload/route.ts
+++ /dev/null
@@ -1,552 +0,0 @@
-import { NextRequest, NextResponse } from 'next/server'
-import { Octokit } from '@octokit/rest'
-import { extname, basename, join } from 'path'
-import { mkdir, writeFile, readFile, unlink, rm } from 'fs/promises'
-import { existsSync } from 'fs'
-import { execFile } from 'child_process'
-import { promisify } from 'util'
-import { createHash } from 'crypto'
-
-const execFileAsync = promisify(execFile)
-
-export const runtime = 'nodejs'
-export const dynamic = 'force-dynamic'
-
-const MODEL_EXTENSIONS = new Set(['.glb', '.gltf'])
-const TEXTURE_EXTENSIONS = new Set(['.png', '.jpg', '.jpeg', '.webp'])
-const ALL_ALLOWED_EXTENSIONS = new Set([...MODEL_EXTENSIONS, ...TEXTURE_EXTENSIONS])
-const REQUIRED_TEXTURES = ['roughness', 'normal', 'metalness', 'color', 'displace']
-const VALID_DESTINATIONS = new Set(['farm', 'map', 'powergrid', 'workshop', 'general', 'environment'])
-
-const TMP_DIR = join('/tmp', 'assets')
-
-function sanitizeFilename(name: string): string {
-  return basename(name)
-    .replace(/[^a-zA-Z0-9._-]/g, '_')
-    .replace(/_{2,}/g, '_')
-    .toLowerCase()
-}
-
-function getOctokit(): Octokit {
-  const token = process.env.GITHUB_TOKEN
-  if (!token) throw new Error('GITHUB_TOKEN non configure')
-  return new Octokit({ auth: token })
-}
-
-function parseRepoUrl(): { owner: string; repo: string } {
-  const url = process.env.GIT_REPO_URL
-  if (!url) throw new Error('GIT_REPO_URL non configure')
-
-  const httpsMatch = url.match(/github\.com\/([^/]+)\/([^/.]+)/)
-  const sshMatch = url.match(/github\.com:([^/]+)\/([^/.]+)/)
-  const shortMatch = url.match(/^([^/]+)\/([^/]+)$/)
-
-  const match = httpsMatch || sshMatch || shortMatch
-  if (!match) throw new Error(`Format GIT_REPO_URL invalide: "${url}"`)
-
-  return { owner: match[1], repo: match[2] }
-}
-
-/** Compute the SHA that Git would assign to a blob with this content */
-function computeGitBlobSha(content: Buffer): string {
-  const header = `blob ${content.length}\0`
-  const store = Buffer.concat([Buffer.from(header), content])
-  return createHash('sha1').update(store).digest('hex')
-}
-
-// ---------------------------------------------------------------------------
-// Blender Draco compression
-// ---------------------------------------------------------------------------
-
-async function compressWithBlender(
-  inputPath: string,
-  outputPath: string
-): Promise<{ success: boolean; error?: string }> {
-  const blenderPath = process.env.BLENDER_PATH || 'blender'
-  const scriptPath = join(process.cwd(), 'scripts', 'compress.py')
-
-  if (!existsSync(scriptPath)) {
-    return { success: false, error: 'scripts/compress.py introuvable' }
-  }
-
-  try {
-    await execFileAsync(blenderPath, [
-      '--background',
-      '--python', scriptPath,
-      '--',
-      '-i', inputPath,
-      '-o', outputPath,
-      '--draco-level', '7',
-      '--texture-size', '512',
-      '-q',
-    ], { timeout: 120_000 })
-
-    if (!existsSync(outputPath)) {
-      return { success: false, error: 'Blender n\'a pas produit de fichier compresse' }
-    }
-
-    return { success: true }
-  } catch (err) {
-    const message = err instanceof Error ? err.message : String(err)
-    return { success: false, error: `Compression Blender echouee: ${message}` }
-  }
-}
-
-// ---------------------------------------------------------------------------
-// Build commit message with checklist
-// ---------------------------------------------------------------------------
-
-function buildCommitMessage(
-  folderName: string,
-  destination: string,
-  modelFilename: string,
-  textureNames: string[],
-  compressed: boolean,
-  isReplace: boolean,
-  fileChanges: Map<string, 'new' | 'changed' | 'unchanged'>,
-  deletedFileNames: string[],
-): string {
-  const title = isReplace
-    ? `update: upload-gltf update -> ${destination}/${folderName}`
-    : `update: upload-gltf add a new model -> ${destination}/${folderName}`
-
-  const lines: string[] = [title, '']
-
-  // Model section — only show if changed or new
-  const modelChange = fileChanges.get(modelFilename.toLowerCase())
-  if (modelChange === 'new') {
-    lines.push('📦 Model')
-    lines.push(`  ✅ ${modelFilename}${compressed ? ' (compressed)' : ''}`)
-  } else if (modelChange === 'changed') {
-    lines.push('📦 Model')
-    lines.push(`  🔄 ${modelFilename}${compressed ? ' (compressed)' : ''}`)
-  }
-  // unchanged → don't show model section at all
-
-  // Textures section — only show lines that have changes
-  const foundTextures = new Set(
-    textureNames.map(t => t.toLowerCase().replace(/\.[^.]+$/, ''))
-  )
-
-  const textureLines: string[] = []
-
-  // Changed or new textures
-  for (const tex of REQUIRED_TEXTURES) {
-    if (foundTextures.has(tex)) {
-      const actual = textureNames.find(t => t.toLowerCase().replace(/\.[^.]+$/, '') === tex)!
-      const change = fileChanges.get(actual.toLowerCase())
-      if (change === 'new') {
-        textureLines.push(`  ✅ ${actual}`)
-      } else if (change === 'changed') {
-        textureLines.push(`  🔄 ${actual}`)
-      }
-      // unchanged → skip
-    } else if (!isReplace) {
-      // Only show missing textures for new uploads
-      textureLines.push(`  ❌ ${tex} (manquant)`)
-    }
-  }
-
-  // Deleted files (orphans removed from remote)
-  for (const name of deletedFileNames) {
-    textureLines.push(`  ❌ ${name} (supprime)`)
-  }
-
-  if (textureLines.length > 0) {
-    lines.push('🎨 Textures')
-    lines.push(...textureLines)
-  }
-
-  return lines.join('\n')
-}
-
-// ---------------------------------------------------------------------------
-// Parse all files from a multi-file FormData
-// ---------------------------------------------------------------------------
-
-interface ParsedFile {
-  filename: string
-  buffer: Buffer
-  isModel: boolean
-  textureName?: string
-}
-
-async function parseMultiUpload(req: NextRequest): Promise<{
-  folderName: string
-  destination: string
-  files: ParsedFile[]
-}> {
-  const formData = await req.formData()
-  const folderName = (formData.get('folderName') as string | null)?.trim() || 'assets'
-  const safeFolderName = sanitizeFilename(folderName).replace(/[^a-zA-Z0-9-_]/g, '-')
-
-  const rawDestination = (formData.get('destination') as string | null)?.trim() || 'general'
-  if (!VALID_DESTINATIONS.has(rawDestination)) {
-    throw new Error(`Destination invalide: "${rawDestination}"`)
-  }
-  const destination = rawDestination
-
-  const fileEntries = formData.getAll('files') as File[]
-  const fileTypes = formData.getAll('fileTypes') as string[]
-  const textureNames = formData.getAll('textureNames') as string[]
-
-  if (fileEntries.length === 0) {
-    throw new Error('Aucun fichier recu')
-  }
-
-  const parsed: ParsedFile[] = []
-
-  for (let i = 0; i < fileEntries.length; i++) {
-    const file = fileEntries[i]
-    if (!file || file.size === 0) continue
-
-    const fileType = fileTypes[i] || 'model'
-    const texName = textureNames[i] || ''
-
-    const originalSafe = sanitizeFilename(file.name)
-    const ext = extname(originalSafe).toLowerCase()
-
-    if (!ALL_ALLOWED_EXTENSIONS.has(ext)) {
-      throw new Error(`Extension non autorisee: "${ext}"`)
-    }
-
-    let filename: string
-    if (fileType === 'texture' && texName) {
-      filename = sanitizeFilename(texName)
-    } else {
-      filename = originalSafe
-    }
-
-    const isModel = MODEL_EXTENSIONS.has(ext)
-    const buffer = Buffer.from(await file.arrayBuffer())
-
-    parsed.push({ filename, buffer, isModel, textureName: texName || undefined })
-  }
-
-  return { folderName: safeFolderName, destination, files: parsed }
-}
-
-// ---------------------------------------------------------------------------
-// Push all files in a single commit
-// ---------------------------------------------------------------------------
-
-async function pushAllToGitHub(
-  folderName: string,
-  files: { path: string; contentBase64: string }[],
-  deletePaths: string[],
-  commitMessage: string
-): Promise<{ commitUrl: string }> {
-  const octokit = getOctokit()
-  const { owner, repo } = parseRepoUrl()
-  const branch = process.env.GIT_BRANCH ?? 'main'
-
-  // 1. Get latest commit on branch
-  const { data: ref } = await octokit.git.getRef({
-    owner,
-    repo,
-    ref: `heads/${branch}`,
-  })
-  const latestCommitSha = ref.object.sha
-
-  // 2. Get that commit's tree
-  const { data: commit } = await octokit.git.getCommit({
-    owner,
-    repo,
-    commit_sha: latestCommitSha,
-  })
-
-  // 3. Create all blobs in parallel
-  const blobResults = await Promise.all(
-    files.map(f =>
-      octokit.git.createBlob({
-        owner,
-        repo,
-        content: f.contentBase64,
-        encoding: 'base64',
-      })
-    )
-  )
-
-  // 4. Create a single tree with all files (add new + delete orphans)
-  const newFilePaths = new Set(files.map(f => f.path))
-  const deleteEntries = deletePaths
-    .filter(p => !newFilePaths.has(p))
-    .map(p => ({
-      path: p,
-      mode: '100644' as const,
-      type: 'blob' as const,
-      sha: null,
-    }))
-
-  const { data: newTree } = await octokit.git.createTree({
-    owner,
-    repo,
-    base_tree: commit.tree.sha,
-    tree: [
-      ...files.map((f, i) => ({
-        path: f.path,
-        mode: '100644' as const,
-        type: 'blob' as const,
-        sha: blobResults[i].data.sha,
-      })),
-      ...deleteEntries,
-    ],
-  })
-
-  // 5. Create a single commit
-  const { data: newCommit } = await octokit.git.createCommit({
-    owner,
-    repo,
-    message: commitMessage,
-    tree: newTree.sha,
-    parents: [latestCommitSha],
-  })
-
-  // 6. Update branch ref
-  await octokit.git.updateRef({
-    owner,
-    repo,
-    ref: `heads/${branch}`,
-    sha: newCommit.sha,
-  })
-
-  return { commitUrl: newCommit.html_url }
-}
-
-// ---------------------------------------------------------------------------
-// GET handler — check if folder already exists on remote
-// ---------------------------------------------------------------------------
-
-export async function GET(req: NextRequest) {
-  const { searchParams } = new URL(req.url)
-  const destination = searchParams.get('destination')?.trim()
-  const folderName = searchParams.get('folderName')?.trim()
-  const secret = req.headers.get('x-upload-secret')
-  const expectedSecret = process.env.UPLOAD_SECRET_KEY
-
-  if (!expectedSecret || !secret || secret !== expectedSecret) {
-    return NextResponse.json({ success: false, error: 'Non autorise' }, { status: 401 })
-  }
-
-  if (!destination || !folderName) {
-    return NextResponse.json({ success: false, error: 'Parametres manquants' }, { status: 400 })
-  }
-
-  if (!VALID_DESTINATIONS.has(destination)) {
-    return NextResponse.json({ success: false, error: 'Destination invalide' }, { status: 400 })
-  }
-
-  const safeFolderName = sanitizeFilename(folderName).replace(/[^a-zA-Z0-9-_]/g, '-')
-  const folderPath = `public/models/${destination}/${safeFolderName}`
-
-  try {
-    const octokit = getOctokit()
-    const { owner, repo } = parseRepoUrl()
-    const branch = process.env.GIT_BRANCH ?? 'main'
-
-    const { data } = await octokit.repos.getContent({
-      owner,
-      repo,
-      path: folderPath,
-      ref: branch,
-    })
-
-    if (Array.isArray(data)) {
-      const existingFiles = data.map(f => ({ name: f.name, sha: f.sha }))
-      return NextResponse.json({
-        success: true,
-        exists: true,
-        path: folderPath,
-        files: existingFiles,
-      })
-    }
-
-    return NextResponse.json({ success: true, exists: false })
-  } catch (err: unknown) {
-    const status = (err as { status?: number })?.status
-    if (status === 404) {
-      return NextResponse.json({ success: true, exists: false })
-    }
-    const message = err instanceof Error ? err.message : 'Erreur inconnue'
-    return NextResponse.json({ success: false, error: message }, { status: 500 })
-  }
-}
-
-// ---------------------------------------------------------------------------
-// POST handler
-// ---------------------------------------------------------------------------
-
-export async function POST(req: NextRequest) {
-  // --- Auth ---
-  const secret = req.headers.get('x-upload-secret')
-  const expectedSecret = process.env.UPLOAD_SECRET_KEY
-
-  if (!expectedSecret) {
-    return NextResponse.json(
-      { success: false, error: 'Configuration serveur incomplete (UPLOAD_SECRET_KEY manquant)' },
-      { status: 500 }
-    )
-  }
-
-  if (!secret || secret !== expectedSecret) {
-    return NextResponse.json(
-      { success: false, error: "Cle d'authentification invalide" },
-      { status: 401 }
-    )
-  }
-
-  // --- Parse all files ---
-  let folderName: string
-  let destination: string
-  let parsedFiles: ParsedFile[]
-
-  try {
-    ;({ folderName, destination, files: parsedFiles } = await parseMultiUpload(req))
-  } catch (err) {
-    const message = err instanceof Error ? err.message : 'Erreur inconnue'
-    return NextResponse.json({ success: false, error: message }, { status: 400 })
-  }
-
-  // --- Process files (compress model if possible) ---
-  const filesToPush: { path: string; contentBase64: string }[] = []
-  let modelFilename = ''
-  let compressed = false
-  let compressionError: string | undefined
-  const textureNames: string[] = []
-
-  for (const pf of parsedFiles) {
-    let content = pf.buffer
-
-    if (pf.isModel) {
-      modelFilename = pf.filename
-
-      // Write to /tmp for Blender compression
-      const tmpFolder = join(TMP_DIR, folderName)
-      await mkdir(tmpFolder, { recursive: true })
-      const tmpFilePath = join(tmpFolder, pf.filename)
-      await writeFile(tmpFilePath, pf.buffer)
-
-      const stem = pf.filename.replace(/\.[^.]+$/, '')
-      const compressedPath = join(tmpFolder, `${stem}_compressed.glb`)
-
-      const result = await compressWithBlender(tmpFilePath, compressedPath)
-
-      if (result.success && existsSync(compressedPath)) {
-        content = await readFile(compressedPath)
-        compressed = true
-        await unlink(compressedPath).catch(() => {})
-      } else {
-        compressionError = result.error
-      }
-
-      await unlink(tmpFilePath).catch(() => {})
-      await rm(tmpFolder, { recursive: true, force: true }).catch(() => {})
-    } else {
-      textureNames.push(pf.filename)
-    }
-
-    filesToPush.push({
-      path: `public/models/${destination}/${folderName}/${pf.filename}`,
-      contentBase64: content.toString('base64'),
-    })
-  }
-
-  // --- Detect existing files and compare SHA to classify changes ---
-  const folderPath = `public/models/${destination}/${folderName}`
-  const remoteFileMap = new Map<string, string>() // name -> sha
-
-  try {
-    const octokit = getOctokit()
-    const { owner, repo } = parseRepoUrl()
-    const branch = process.env.GIT_BRANCH ?? 'main'
-
-    const { data } = await octokit.repos.getContent({
-      owner,
-      repo,
-      path: folderPath,
-      ref: branch,
-    })
-
-    if (Array.isArray(data)) {
-      for (const f of data) {
-        remoteFileMap.set(f.name.toLowerCase(), f.sha)
-      }
-    }
-  } catch {
-    // 404 = folder doesn't exist yet
-  }
-
-  const isReplace = remoteFileMap.size > 0
-
-  // Classify each file: changed, new, or unchanged
-  type FileChange = 'new' | 'changed' | 'unchanged'
-  const fileChanges = new Map<string, FileChange>()
-  const changedFilesToPush: { path: string; contentBase64: string }[] = []
-
-  for (const f of filesToPush) {
-    const filename = f.path.split('/').pop()!
-    const localSha = computeGitBlobSha(Buffer.from(f.contentBase64, 'base64'))
-    const remoteSha = remoteFileMap.get(filename.toLowerCase())
-
-    if (!remoteSha) {
-      fileChanges.set(filename.toLowerCase(), 'new')
-      changedFilesToPush.push(f)
-    } else if (remoteSha !== localSha) {
-      fileChanges.set(filename.toLowerCase(), 'changed')
-      changedFilesToPush.push(f)
-    } else {
-      fileChanges.set(filename.toLowerCase(), 'unchanged')
-      // skip — don't push unchanged files
-    }
-  }
-
-  // Files on remote that are not in the new upload → will be deleted (orphans)
-  const newFileNames = new Set(filesToPush.map(f => f.path.split('/').pop()!.toLowerCase()))
-  const deletedFileNames: string[] = []
-  const deletePaths: string[] = []
-  for (const [name] of remoteFileMap) {
-    if (!newFileNames.has(name)) {
-      deletedFileNames.push(name)
-      deletePaths.push(`${folderPath}/${name}`)
-    }
-  }
-
-  // If nothing changed at all, don't create an empty commit
-  if (changedFilesToPush.length === 0 && deletePaths.length === 0) {
-    return NextResponse.json({
-      success: true,
-      folderName,
-      filesCount: 0,
-      compressed,
-      compressionError: compressionError || undefined,
-      message: 'Aucun fichier modifie — rien a envoyer.',
-    })
-  }
-
-  // --- Build commit message ---
-  const commitMessage = buildCommitMessage(
-    folderName, destination, modelFilename, textureNames,
-    compressed, isReplace, fileChanges, deletedFileNames,
-  )
-
-  // --- Push all in one commit ---
-  try {
-    const { commitUrl } = await pushAllToGitHub(folderName, changedFilesToPush, deletePaths, commitMessage)
-
-    return NextResponse.json({
-      success: true,
-      folderName,
-      filesCount: changedFilesToPush.length,
-      compressed,
-      compressionError: compressionError || undefined,
-      message: `${changedFilesToPush.length} fichier(s) modifie(s) envoye(s) sur GitHub en un seul commit.`,
-      commitUrl,
-    })
-  } catch (err) {
-    const message = err instanceof Error ? err.message : 'Erreur GitHub inconnue'
-    return NextResponse.json(
-      { success: false, error: `Push GitHub echoue: ${message}` },
-      { status: 500 }
-    )
-  }
-}
diff --git a/components/UploadZone.tsx b/components/UploadZone.tsx
index 480f371..98fe6f0 100644
--- a/components/UploadZone.tsx
+++ b/components/UploadZone.tsx
@@ -118,7 +118,7 @@ async function checkFolderDiffs(
 ): Promise<CheckResult> {
   try {
     const params = new URLSearchParams({ folderName: folder.folderName, destination })
-    const res = await fetch(`/api/upload?${params}`, {
+    const res = await fetch(`/api/upload/check?${params}`, {
       headers: { 'x-upload-secret': secret.trim() },
     })
     const data = await res.json()
@@ -195,7 +195,7 @@ async function uploadFolder(
   onProgress(10)
 
   try {
-    const res = await fetch('/api/upload', {
+    const res = await fetch('/api/upload/git', {
       method: 'POST',
       headers: { 'x-upload-secret': secret.trim() },
       body: formData,
diff --git a/lib/auth.ts b/lib/auth.ts
new file mode 100644
index 0000000..1d883bd
--- /dev/null
+++ b/lib/auth.ts
@@ -0,0 +1,39 @@
+import { timingSafeEqual } from 'crypto'
+import { NextRequest, NextResponse } from 'next/server'
+
+/**
+ * Validate the upload secret from request headers.
+ * Returns null if valid, or a NextResponse error if invalid.
+ */
+export function validateUploadSecret(req: NextRequest): NextResponse | null {
+  const secret = req.headers.get('x-upload-secret')
+  const expectedSecret = process.env.UPLOAD_SECRET_KEY
+
+  if (!expectedSecret) {
+    return NextResponse.json(
+      { success: false, error: 'Configuration serveur incomplete (UPLOAD_SECRET_KEY manquant)' },
+      { status: 500 },
+    )
+  }
+
+  if (!secret) {
+    return NextResponse.json(
+      { success: false, error: "Cle d'authentification manquante" },
+      { status: 401 },
+    )
+  }
+
+  // Timing-safe comparison to prevent timing attacks
+  const a = Buffer.from(secret)
+  const b = Buffer.from(expectedSecret)
+  const isValid = a.length === b.length && timingSafeEqual(a, b)
+
+  if (!isValid) {
+    return NextResponse.json(
+      { success: false, error: "Cle d'authentification invalide" },
+      { status: 401 },
+    )
+  }
+
+  return null
+}
diff --git a/lib/blender.ts b/lib/blender.ts
new file mode 100644
index 0000000..6a035e6
--- /dev/null
+++ b/lib/blender.ts
@@ -0,0 +1,49 @@
+import { join } from 'path'
+import { existsSync } from 'fs'
+import { execFile } from 'child_process'
+import { promisify } from 'util'
+
+const execFileAsync = promisify(execFile)
+
+/**
+ * Compress a GLTF/GLB model using Blender's Draco compression.
+ * Returns { success: true } on success, or { success: false, error } on failure.
+ * Callers should fall back to the original file on failure.
+ */
+export async function compressWithBlender(
+  inputPath: string,
+  outputPath: string,
+): Promise<{ success: boolean; error?: string }> {
+  const blenderPath = process.env.BLENDER_PATH || 'blender'
+  const scriptPath = join(process.cwd(), 'scripts', 'compress.py')
+
+  if (!existsSync(scriptPath)) {
+    return { success: false, error: 'scripts/compress.py introuvable' }
+  }
+
+  try {
+    await execFileAsync(
+      blenderPath,
+      [
+        '--background',
+        '--python', scriptPath,
+        '--',
+        '-i', inputPath,
+        '-o', outputPath,
+        '--draco-level', '7',
+        '--texture-size', '512',
+        '-q',
+      ],
+      { timeout: 120_000 },
+    )
+
+    if (!existsSync(outputPath)) {
+      return { success: false, error: "Blender n'a pas produit de fichier compresse" }
+    }
+
+    return { success: true }
+  } catch (err) {
+    const message = err instanceof Error ? err.message : String(err)
+    return { success: false, error: `Compression Blender echouee: ${message}` }
+  }
+}
diff --git a/lib/commit-message.ts b/lib/commit-message.ts
new file mode 100644
index 0000000..2dca9a4
--- /dev/null
+++ b/lib/commit-message.ts
@@ -0,0 +1,72 @@
+import { REQUIRED_TEXTURES } from './constants'
+import type { FileChange } from './types'
+
+/**
+ * Build a formatted commit message based on the upload context.
+ *
+ * Symbols:
+ * - ✅ = new file
+ * - 🔄 = modified file
+ * - ❌ = missing texture (new upload) or deleted file (update)
+ * - Unchanged files are omitted entirely
+ */
+export function buildCommitMessage(
+  folderName: string,
+  destination: string,
+  modelFilename: string,
+  textureNames: string[],
+  compressed: boolean,
+  isReplace: boolean,
+  fileChanges: Map<string, FileChange>,
+  deletedFileNames: string[],
+): string {
+  const title = isReplace
+    ? `update: upload-gltf update -> ${destination}/${folderName}`
+    : `update: upload-gltf add a new model -> ${destination}/${folderName}`
+
+  const lines: string[] = [title, '']
+
+  // Model section — only show if changed or new
+  const modelChange = fileChanges.get(modelFilename.toLowerCase())
+  if (modelChange === 'new') {
+    lines.push('📦 Model')
+    lines.push(`  ✅ ${modelFilename}${compressed ? ' (compressed)' : ''}`)
+  } else if (modelChange === 'changed') {
+    lines.push('📦 Model')
+    lines.push(`  🔄 ${modelFilename}${compressed ? ' (compressed)' : ''}`)
+  }
+
+  // Textures section — only show lines that have changes
+  const foundTextures = new Set(
+    textureNames.map((t) => t.toLowerCase().replace(/\.[^.]+$/, '')),
+  )
+
+  const textureLines: string[] = []
+
+  for (const tex of REQUIRED_TEXTURES) {
+    if (foundTextures.has(tex)) {
+      const actual = textureNames.find(
+        (t) => t.toLowerCase().replace(/\.[^.]+$/, '') === tex,
+      )!
+      const change = fileChanges.get(actual.toLowerCase())
+      if (change === 'new') {
+        textureLines.push(`  ✅ ${actual}`)
+      } else if (change === 'changed') {
+        textureLines.push(`  🔄 ${actual}`)
+      }
+    } else if (!isReplace) {
+      textureLines.push(`  ❌ ${tex} (manquant)`)
+    }
+  }
+
+  for (const name of deletedFileNames) {
+    textureLines.push(`  ❌ ${name} (supprime)`)
+  }
+
+  if (textureLines.length > 0) {
+    lines.push('🎨 Textures')
+    lines.push(...textureLines)
+  }
+
+  return lines.join('\n')
+}
diff --git a/lib/constants.ts b/lib/constants.ts
new file mode 100644
index 0000000..5607b67
--- /dev/null
+++ b/lib/constants.ts
@@ -0,0 +1,29 @@
+// ---------------------------------------------------------------------------
+// Shared constants — used by both client and server
+// ---------------------------------------------------------------------------
+
+export const MODEL_EXTENSIONS = new Set(['.glb', '.gltf'])
+export const TEXTURE_EXTENSIONS = new Set(['.png', '.jpg', '.jpeg', '.webp'])
+export const ALL_ALLOWED_EXTENSIONS = new Set([...MODEL_EXTENSIONS, ...TEXTURE_EXTENSIONS])
+
+export const REQUIRED_TEXTURES = ['roughness', 'normal', 'metalness', 'color', 'displace'] as const
+
+export const VALID_DESTINATIONS = new Set([
+  'farm', 'map', 'powergrid', 'workshop', 'general', 'environment',
+] as const)
+
+export const DESTINATIONS = [
+  { value: 'farm', label: 'Farm' },
+  { value: 'map', label: 'Map' },
+  { value: 'powergrid', label: 'Powergrid' },
+  { value: 'workshop', label: 'Workshop' },
+  { value: 'general', label: 'General' },
+  { value: 'environment', label: 'Environment' },
+] as const
+
+export type Destination = typeof DESTINATIONS[number]['value']
+
+export const TMP_DIR = '/tmp/assets'
+
+/** Maximum file size in bytes (100 MB) */
+export const MAX_FILE_SIZE = 100 * 1024 * 1024
diff --git a/lib/github.ts b/lib/github.ts
new file mode 100644
index 0000000..39ecc36
--- /dev/null
+++ b/lib/github.ts
@@ -0,0 +1,156 @@
+import { Octokit } from '@octokit/rest'
+import { createHash } from 'crypto'
+import type { RemoteFile } from './types'
+
+// ---------------------------------------------------------------------------
+// Octokit helpers
+// ---------------------------------------------------------------------------
+
+export function getOctokit(): Octokit {
+  const token = process.env.GITHUB_TOKEN
+  if (!token) throw new Error('GITHUB_TOKEN non configure')
+  return new Octokit({ auth: token })
+}
+
+export function parseRepoUrl(): { owner: string; repo: string } {
+  const url = process.env.GIT_REPO_URL
+  if (!url) throw new Error('GIT_REPO_URL non configure')
+
+  const httpsMatch = url.match(/github\.com\/([^/]+)\/([^/.]+)/)
+  const sshMatch = url.match(/github\.com:([^/]+)\/([^/.]+)/)
+  const shortMatch = url.match(/^([^/]+)\/([^/]+)$/)
+
+  const match = httpsMatch || sshMatch || shortMatch
+  if (!match) throw new Error(`Format GIT_REPO_URL invalide: "${url}"`)
+
+  return { owner: match[1], repo: match[2] }
+}
+
+/** Compute the SHA that Git would assign to a blob with this content */
+export function computeGitBlobSha(content: Buffer): string {
+  const header = `blob ${content.length}\0`
+  const store = Buffer.concat([Buffer.from(header), content])
+  return createHash('sha1').update(store).digest('hex')
+}
+
+// ---------------------------------------------------------------------------
+// Read remote folder contents (with SHA per file)
+// ---------------------------------------------------------------------------
+
+export async function getRemoteFolder(
+  folderPath: string,
+): Promise<{ exists: boolean; files: RemoteFile[] }> {
+  const octokit = getOctokit()
+  const { owner, repo } = parseRepoUrl()
+  const branch = process.env.GIT_BRANCH ?? 'main'
+
+  try {
+    const { data } = await octokit.repos.getContent({
+      owner,
+      repo,
+      path: folderPath,
+      ref: branch,
+    })
+
+    if (Array.isArray(data)) {
+      return {
+        exists: true,
+        files: data.map((f) => ({ name: f.name, sha: f.sha })),
+      }
+    }
+
+    return { exists: false, files: [] }
+  } catch (err: unknown) {
+    const status = (err as { status?: number })?.status
+    if (status === 404) {
+      return { exists: false, files: [] }
+    }
+    throw err
+  }
+}
+
+// ---------------------------------------------------------------------------
+// Push all files in a single commit (with optional deletions)
+// ---------------------------------------------------------------------------
+
+export async function pushAllToGitHub(
+  files: { path: string; contentBase64: string }[],
+  deletePaths: string[],
+  commitMessage: string,
+): Promise<{ commitUrl: string }> {
+  const octokit = getOctokit()
+  const { owner, repo } = parseRepoUrl()
+  const branch = process.env.GIT_BRANCH ?? 'main'
+
+  // 1. Get latest commit on branch
+  const { data: ref } = await octokit.git.getRef({
+    owner,
+    repo,
+    ref: `heads/${branch}`,
+  })
+  const latestCommitSha = ref.object.sha
+
+  // 2. Get that commit's tree
+  const { data: commit } = await octokit.git.getCommit({
+    owner,
+    repo,
+    commit_sha: latestCommitSha,
+  })
+
+  // 3. Create all blobs in parallel
+  const blobResults = await Promise.all(
+    files.map((f) =>
+      octokit.git.createBlob({
+        owner,
+        repo,
+        content: f.contentBase64,
+        encoding: 'base64',
+      }),
+    ),
+  )
+
+  // 4. Build tree entries: new/changed files + deletions
+  const newFilePaths = new Set(files.map((f) => f.path))
+  const deleteEntries = deletePaths
+    .filter((p) => !newFilePaths.has(p))
+    .map((p) => ({
+      path: p,
+      mode: '100644' as const,
+      type: 'blob' as const,
+      sha: null,
+    }))
+
+  const { data: newTree } = await octokit.git.createTree({
+    owner,
+    repo,
+    base_tree: commit.tree.sha,
+    tree: [
+      ...files.map((f, i) => ({
+        path: f.path,
+        mode: '100644' as const,
+        type: 'blob' as const,
+        sha: blobResults[i].data.sha,
+      })),
+      ...deleteEntries,
+    ],
+  })
+
+  // 5. Create a single commit
+  const { data: newCommit } = await octokit.git.createCommit({
+    owner,
+    repo,
+    message: commitMessage,
+    tree: newTree.sha,
+    parents: [latestCommitSha],
+  })
+
+  // 6. Update branch ref
+  await octokit.git.updateRef({
+    owner,
+    repo,
+    ref: `heads/${branch}`,
+    sha: newCommit.sha,
+  })
+
+  return { commitUrl: newCommit.html_url }
+}
diff --git a/lib/parse-upload.ts b/lib/parse-upload.ts
new file mode 100644
index 0000000..a3d623c
--- /dev/null
+++ b/lib/parse-upload.ts
@@ -0,0 +1,80 @@
+import { extname } from 'path'
+import { NextRequest } from 'next/server'
+import { sanitizeFilename } from './sanitize'
+import { ALL_ALLOWED_EXTENSIONS, MODEL_EXTENSIONS, VALID_DESTINATIONS, MAX_FILE_SIZE } from './constants'
+import type { ParsedFile } from './types'
+
+/**
+ * Parse a multi-file FormData upload request.
+ * Validates destination, file extensions, file sizes, and returns parsed files.
+ */
+export async function parseMultiUpload(req: NextRequest): Promise<{
+  folderName: string
+  destination: string
+  files: ParsedFile[]
+}> {
+  const formData = await req.formData()
+  const folderName = (formData.get('folderName') as string | null)?.trim() || 'assets'
+  const safeFolderName = sanitizeFilename(folderName).replace(/[^a-zA-Z0-9-_]/g, '-')
+
+  const rawDestination = (formData.get('destination') as string | null)?.trim() || 'general'
+  if (!VALID_DESTINATIONS.has(rawDestination as never)) {
+    throw new Error(`Destination invalide: "${rawDestination}"`)
+  }
+  const destination = rawDestination
+
+  const rawFiles = formData.getAll('files')
+  const fileTypes = formData.getAll('fileTypes') as string[]
+  const textureNames = formData.getAll('textureNames') as string[]
+
+  // Runtime validation: ensure entries are actual File objects
+  const fileEntries: File[] = []
+  for (const entry of rawFiles) {
+    if (!(entry instanceof File)) {
+      throw new Error('Donnees de fichier invalides')
+    }
+    fileEntries.push(entry)
+  }
+
+  if (fileEntries.length === 0) {
+    throw new Error('Aucun fichier recu')
+  }
+
+  const parsed: ParsedFile[] = []
+
+  for (let i = 0; i < fileEntries.length; i++) {
+    const file = fileEntries[i]
+    if (!file || file.size === 0) continue
+
+    // File size limit
+    if (file.size > MAX_FILE_SIZE) {
+      throw new Error(
+        `Fichier "${file.name}" trop volumineux (${(file.size / 1024 / 1024).toFixed(1)} MB). Maximum: ${MAX_FILE_SIZE / 1024 / 1024} MB.`,
+      )
+    }
+
+    const fileType = fileTypes[i] || 'model'
+    const texName = textureNames[i] || ''
+
+    const originalSafe = sanitizeFilename(file.name)
+    const ext = extname(originalSafe).toLowerCase()
+
+    if (!ALL_ALLOWED_EXTENSIONS.has(ext)) {
+      throw new Error(`Extension non autorisee: "${ext}"`)
+    }
+
+    let filename: string
+    if (fileType === 'texture' && texName) {
+      filename = sanitizeFilename(texName)
+    } else {
+      filename = originalSafe
+    }
+
+    const isModel = MODEL_EXTENSIONS.has(ext)
+    const buffer = Buffer.from(await file.arrayBuffer())
+
+    parsed.push({ filename, buffer, isModel, textureName: texName || undefined })
+  }
+
+  return { folderName: safeFolderName, destination, files: parsed }
+}
diff --git a/lib/sanitize.ts b/lib/sanitize.ts
new file mode 100644
index 0000000..2f6d09a
--- /dev/null
+++ b/lib/sanitize.ts
@@ -0,0 +1,12 @@
+import { basename } from 'path'
+
+/**
+ * Sanitize a filename: strip path components, replace special chars,
+ * collapse underscores, lowercase.
+ */
+export function sanitizeFilename(name: string): string {
+  return basename(name)
+    .replace(/[^a-zA-Z0-9._-]/g, '_')
+    .replace(/_{2,}/g, '_')
+    .toLowerCase()
+}
diff --git a/lib/types.ts b/lib/types.ts
new file mode 100644
index 0000000..6cba74a
--- /dev/null
+++ b/lib/types.ts
@@ -0,0 +1,37 @@
+// ---------------------------------------------------------------------------
+// Shared types
+// ---------------------------------------------------------------------------
+
+export interface ParsedFile {
+  filename: string
+  buffer: Buffer
+  isModel: boolean
+  textureName?: string
+}
+
+export type FileChange = 'new' | 'changed' | 'unchanged'
+
+export interface FileDiff {
+  name: string
+  status: 'changed' | 'new' | 'deleted'
+}
+
+export interface RemoteFile {
+  name: string
+  sha: string
+}
+
+export type UploadResponse =
+  | {
+      success: true
+      folderName: string
+      filesCount: number
+      compressed: boolean
+      compressionError?: string
+      message: string
+      commitUrl?: string
+    }
+  | {
+      success: false
+      error: string
+    }