All you need to do is paste a link to a YouTube playlist (or to a video that’s part of a playlist) and it will be converted into a course. You can also convert it directly from YouTube by changing “youtube” in the URL to “withadept”.
All progress is stored locally and registration is optional (an account lets you sync progress across devices). The browser can reject the request to enable persistent storage, and in that case app shows message with suggestion to sign in (you can just dismiss it), but otherwise I tried to avoid pushing that option.
There is no tracking, no 3rd-party cookies (there is youtube-nocookie.com embed on playlist page that I can't avoid), no marketing emails if you do sign up.
For those curious about the tech-stack: it’s a Vue/Nuxt app leaning heavily on Cloudflare (Workers, D1, R2, Email Service). I also use OpenRouter to access models that clean up video titles (doing it in code wasn’t reliable because titles often have inconsistent format, and doing it with an LLM is actually very cheap - ~$0.0003 for 40 video playlist).
[1] As it’s 2026 “I built” means “me and Claude Code built”. It was AI-assisted (not vibecoded). I leaned heavily on Claude Code for designing the UI (which hopefully isn’t too obvious), but the logic and architecture were either written manually or AI-assisted and reviewed.