rspad
Offline First • Single Binary

The instant scratchpad for Rust snippets.

Like RunJS, but for Rust. A lightweight background daemon written in Axum that mounts a Monaco editor on localhost, compiles locally with your native rustc, and streams terminal execution output in milliseconds.

http://localhost:7878 main.rs
fn main() {
  let primes = vec![2, 3, 5, 7, 11];
  println!("Primes: {:?}", primes);
}
// Finished in 0.08s Primes: [2, 3, 5, 7, 11]
Quickstart Setup
01 Ensure Rust & Cargo are installed
If you haven't installed Rust yet, grab the official toolchain installer via rustup:
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
02 Install rspad via Cargo
Compile and install the lightweight daemon directly to your local system path:
cargo install rspad
03 Launch the scratchpad
Spins up the Axum server on port 7878 and automatically opens your browser:
rspad
Design Principles
No Databases, Zero State
Source files are compiled inside ephemeral memory-backed tempdirs and cleaned up via RAII as soon as execution terminates.
Embedded Frontend
All UI assets and Monaco completion maps are compiled directly into the binary using rust-embed.
Execution Guard
Child processes are spawned with isolated pipes and a 10-second ceiling to prevent runaway loop {} execution.
Auto Port Fallback
If 7878 is occupied by another process, rspad automatically finds and binds the next consecutive open port.