I am looking for a backend engineer with strong experience in FFmpeg and video transcoding to fix our current upload system where MP4 uploads work but all non-MP4 formats fail. The goal is to ensure full support for MOV, M4V, MKV, AVI, WMV, FLV and other major formats, convert everything to MP4 using FFmpeg, fix iPhone MOV rotation metadata, resolve audio issues, and ensure the final videos play correctly on iPhone, Android, and desktop browsers. You will repair the upload-to-queue-to-worker pipeline, improve error logging, and provide basic testing documentation. Required experience includes FFmpeg, Node.js or Python, and queue systems such as Bull, Celery, or similar. The total budget is fixed at $200 and the work must be completed in 6–8 days. To apply, please answer the following: which video formats you have handled with FFmpeg; provide one real FFmpeg command you have used; describe a transcoding pipeline you previously built (2–3 sentences); explain how you handle iPhone MOV rotation metadata; list queue systems you have worked with; and share a link to any project where you implemented video uploading or transcoding. You must be able to start immediately.