Windows
Always call curl.exe in Windows PowerShell. The curl alias is Invoke-WebRequest.
PowerShell
Always curl.exe. Details and the native Invoke-WebRequest form: Running → PowerShell.
curl.exe -fsSL https://runny.sh/r/{slug} | pwshcmd.exe
curl.exe -fsSL https://runny.sh/r/{slug} | bashcmd.exe’s curl.exe is real curl. You still need a runtime on the PATH (bash from Git for Windows, pwsh, python, or node).