I took a deadlift video from r/formcheck, fed it to a Python script, and got back prioritized coaching cues. All running locally on my laptop. No cloud APIs, no subscriptions. Just MediaPipe for pose estimation, OpenCV for frame extraction, and Qwen 3.5-9B running on llama.cpp for natural-language feedback. The Idea r/formcheck is a subreddit where lifters post videos of their sets and ask for feedback. You film your deadlift, upload it, and wait for someone (hopefully qualified) to tell you what to fix. The problem is that feedback is inconsistent, slow, and often contradictory. [read more]