Hello Codeforces,
A few friends and I (with the help of saarang, vishesh312, nishuz, and ritul_kr_singh) hacked together an open-source version of OIChecklist in the past week. It's available here! Check out the GitHub repository here. The web app pulls the problem data from this file, further instructions on how to edit and contribute are mentioned in the repository. All feedback, issues (and accompanying PRs :p) are welcome – we would love to hear how to improve this further.
PS: We also released a (similar) checklist for technical interview preparation, check that out too if you're interested!