Code Execution with dev

Execute code directly using the Bash tool. No wrapper, no persistent files, no cleanup needed beyond what the code itself creates.

Run code inline

JavaScript / TypeScript

bun -e "const fs = require('fs'); console.log(fs.readdirSync('.'))" bun -e "import { readFileSync } from 'fs'; console.log(readFileSync('package.json', 'utf-8'))"

Run a file

bun run script.ts node script.js

Python

python -c "import json; print(json.dumps({'ok': True}))"

Shell

bash -c "ls -la && cat package.json"

File operations (inline, no temp files)

Read

bun -e "console.log(require('fs').readFileSync('path/to/file', 'utf-8'))"

Write

bun -e "require('fs').writeFileSync('out.json', JSON.stringify({x:1}, null, 2))"

Stat / exists

bun -e "const fs=require('fs'); console.log(fs.existsSync('file.txt'), fs.statSync?.('.')?.size)"

Rules

• Each run under 15 seconds

• Pack every related hypothesis into one run — never one idea per run

• No persistent temp files; if a temp file is needed, delete it in the same command

• No spawn/exec/fork inside executed code

• Use bun over node when available