Runner is a program to run multiple executables in parallel. I mostly use it to run a server program while also rebuilding a frontend in the background. The configuration for it is through a kdl file in the directory it is invoked from. Here's an example config file:
run "frontend" {
path "frontend"
command "npm"
args "run" "dev"
}
run "backend" {
path "backend"
command "cargo"
args "run" "--color=always"
}
This builds a frontend through npm and a cargo server to actually run the backend server. It takes paths to run the commands in as their working directory, arguments are optional if not needed.