my app keeps losing uploaded files after redeploying

That usually means your uploaded files are being stored somewhere ephemeral inside the app container or VM, and redeploying replaces that storage.

Common causes

1. Files saved inside the app’s local filesystem

   • Example: uploading to ./uploads, /tmp, /var/www/uploads, etc.
   • On redeploy, container rebuild, restart, or new instance creation, those files may disappear.

2. Running in containers without a persistent volume

   • Docker/Kubernetes/Heroku/Render/Fly/etc. often give you ephemeral disk unless you explicitly mount persistent storage.

3. Multiple instances/load balancing

   • Upload goes to one instance, but after redeploy or scaling, requests hit another instance that doesn’t have the file.

4. Build/deploy process overwrites the directory

   • If your uploads directory is inside the project folder that gets replaced during deployment, uploaded files get wiped.

Best practice

Store uploaded files in persistent external storage, such as:

• Amazon S3
• Google Cloud Storage
• Azure Blob Storage
• Cloudinary (for images/media)
• A mounted persistent disk/volume
• A dedicated file server/NAS

Then store only the file URL/path in your database.

If you want to keep local storage

Make sure uploads go to a path that is:

• outside the deployed code directory, and
• mounted as a persistent volume/disk.

Examples

• Docker: mount a volume like /data/uploads
• Kubernetes: use a PersistentVolumeClaim
• Render/Fly/Heroku: use their persistent disk options, or switch to object storage
• AWS EC2: use EBS or another mounted persistent disk

Quick check

Look at your upload code and ask:

• Is it saving to a folder inside the app repo?
• Is that folder included in the deployment artifact?
• Is there any persistent volume mounted there?

If you want, paste:

• your deployment platform,
• your upload code,
• and where files are being saved,

and I can tell you exactly what’s causing it and how to fix it.