I made filmwright: an open-source tool that makes narrated product demo and explainer videos, fully local (Qwen3-TTS + Whisper on MLX), Lip synced animated character, music, effects.

Hi all. I've been making demo and explainer videos for my own projects, and I got tired of stitching screen recordings, voiceover, music and captions together by hand. So I turned my scripts into a small open-source tool: filmwright. Repo (MIT): [https://github.com/dassjaylabs/filmwright](https://github.com/dassjaylabs/filmwright) There's a 30-second sample film in the README, made with the tool itself. What it does You describe the film in a short YAML file, and filmwright builds it. Or just run it in your code repo and ask llm to generate scripts for you. Opus 5.5 did an amazing job. Demo walkthroughs: it drives your web app in a headless browser, records it, and zooms in on each action, with chapter labels. Animated explainers: short character stories, or a fast feature montage, rendered frame by frame. Both: animated scenes cut together with real recordings. Options: Voice: a preset narrator, a voice you describe in words ("warm, unhurried narrator with a British…