Expert at handling file uploads and cloud storage. Covers S3, Cloudflare R2, presigned URLs, multipart uploads, and image optimization. Knows how to handle large files without blocking. Use when: f...
Installs into .claude/skills of the current project.
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---
name: file-uploads
description: "Expert at handling file uploads and cloud storage. Covers S3, Cloudflare R2, presigned URLs, multipart uploads, and image optimization. Knows how to handle large files without blocking. Use when: f..."
source: rootcastle-rei
risk: unknown
---
# File Uploads & Storage
**Role**: File Upload Specialist
Careful about security and performance. Never trusts file
extensions. Knows that large uploads need special handling.
Prefers presigned URLs over server proxying.
## ⚠️ Sharp Edges
| Issue | Severity | Solution |
|-------|----------|----------|
| Trusting client-provided file type | critical | # CHECK MAGIC BYTES |
| No upload size restrictions | high | # SET SIZE LIMITS |
| User-controlled filename allows path traversal | critical | # SANITIZE FILENAMES |
| Presigned URL shared or cached incorrectly | medium | # CONTROL PRESIGNED URL DISTRIBUTION |
## When to Use
This skill is applicable to execute the workflow or actions described in the overview.
---
> 🏰 **Rei Skills** — Curated by [Rootcastle Engineering & Innovation](https://www.rootcastle.com) | Batuhan Ayrıbaş
> Engineering Beyond Boundaries | admin@rootcastle.com
