Multi-SNS Creator Upload Platform

We're building a creator-friendly hub where users drop their images or videos once and see them appear automatically on Facebook, Instagram, YouTube and TikTok. Accompanying each post , a hash of the file plus its metadata should be written to the blockchain—Ethereum or, if you feel it’s more cost-effective, Polygon—so the publication record is public, immutable and easy to verify.

Here’s the flow I have in mind: the creator uploads an image or video, chooses the networks, adds captions or tags, and hits publish. Your code then calls the relevant APIs (Facebook & Instagram Graph, YouTube Data, TikTok) and reports back successful links. Immediately after, a smart contract stores the content hash, timestamp and the list of networks where the post now lives. The dashboard should show status, on-chain transaction ID and basic analytics, plus leave room to add other networks or even text-only formats later.

Deliverables
• Front-end uploader and dashboard (web or cross-platform mobile)
• Back-end service that queues and posts to all four networks, handles retries and rate limits
• Solidity (or comparable) smart contract, with a simple interface for recording the post hash and retrieving proofs
• Documentation and demo showing one end-to-end publish cycle

I’m happy to discuss the exact tech stack, but seamless multi-SNS posting and engagement tracking are the two must-haves. Let me know how you’d approach the API integrations and which chain—Ethereum or Polygon—you’d lean toward for keeping gas reasonable.
Quite some parts are done , need to pick up and wrap up