The most battletested way is via bindings to other languages. Ex. mlua with luau sandboxing Or Javascript via v8 or deno_core

There are also a few languages implemented in rust like rhai

There is also the option of compiling the user code to wasm and using wasmtime to run it

Standard forgejo shoutout. It is a fork of gitea with more features following the foss philosophy. It is codeberg’s backend https://forgejo.org/2024-02-monthly-update/

Primary code editor: helix

Graphical debugger and certain IDE features: vscodium

Lots of open source language servers: clangd, rust-analyzer, perl-navigator, …

Makefile to compile-comands.json: bear

TUI file manager: yazi

Better Grep:ripgrep

Debugger: gdb(gnu debugger)

Same as I use it on discord. Either to justify a block/mute or to remind me why I should block/mute someone the next time it bothers me