A real code editor and a real execution backend, not a toy. Pick a language, write something, hit Run — actual compilers and interpreters do the work, via a self-hosted Judge0 sandbox. No installs, no account, no tracking.
Every run goes to Judge0 — an open-source sandboxed execution engine. Actual compilers and interpreters, real exit codes, real timing and memory numbers.
Monaco — the same editor engine behind VS Code — with per-language syntax highlighting and autocomplete snippets, not a plain textarea.
Feed your program input, see compile errors and stderr clearly, and runaway loops get stopped by Judge0's own resource limits.
The execution backend is self-hostable via Docker — your code doesn't have to leave infrastructure you control.
Testing a snippet, checking how a language handles something, or following along with a tutorial shouldn't require installing a toolchain first. This is a small, honest tool for that: open a tab, write code, run it, see real output — nothing else in the way.