Offload R2 Asset

Host media on https://remotion.media/, update every in-scope source reference to the public object, and remove the repository-local copy after verification.

Workflow

1. Find the main worktree with git worktree list --porcelain. Prefer the worktree on refs/heads/main, normally /Users/jonathanburger/remotion.

2. Choose a stable, descriptive object key. Use a feature-specific directory prefix when it prevents collisions, for example studio-close-ups/demo.mp4. When replacing an asset, prefer a new versioned key so browser and Studio caches cannot serve the previous bytes.

3. Load credentials from the main worktree without printing them:

   --env-file=/Users/jonathanburger/remotion/packages/remotion-media/.env
   

   The required variables are AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY.