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05 / Full-stack engineer2026shipped

Mov to MP4.

A local-first .mov to .mp4 converter. Drop a QuickTime file in the browser, watch real progress, download the result — nothing leaves your machine that doesn't have to.

07 / mov→mp4

mov to mp4.

the work

Next.js 16 App Router app: drop one or many .mov files, the server route handler spawns ffmpeg/ffprobe, progress streams back to the browser over Server-Sent Events, and the converted MP4 downloads via a plain GET. Temp files live in os.tmpdir() and self-clean on download or after a 10-minute TTL. No accounts, no telemetry, no upload caps beyond the box's RAM.

highlights

  • 01

    Live ffmpeg progress streamed over Server-Sent Events, no polling

  • 02

    H.264 + AAC with the faststart flag so the output streams without a re-mux

  • 03

    Temp files auto-clean on download or after a 10-minute TTL — nothing lingers in /tmp