Web
Praxis Codicis
Browser-only coding practice — playground, problems, and HTML preview. No remote code execution.
Praxis Codicis is a coding practice site that runs user code only in the visitor’s browser. Open a playground language, solve short problems with client-side tests, or preview HTML/CSS/JS in a sandbox iframe.
Features
Supported languages for free play and judged problems: JavaScript, TypeScript, Python, SQL, and Lua. C/C++ is experimental via Wasmer Clang. Progress, drafts, and bookmarks stay in localStorage on your device. There is no account wall.
Safety model
The site does not send your code to a remote judge or compile server. Static hosting on Cloudflare Pages only. That keeps the product on a free-tier path and avoids hosting arbitrary code on POL infrastructure.
How to use it
Open https://phaseoutlimit-coding.pages.dev/ , start at Playground or Problems, and use Progress to export a JSON backup if you want. For feedback, email [email protected] with “Praxis Codicis” in the subject.