npm
If you have a folder with subfolders, and you want to access each subfolder at the project root directory, you can use the built-in --prefix.
For example:
"scripts": {
"client": "npm start --prefix client",
"server": "npm start --prefix server",
}
You'll need different terminals to keep the apps running though: npm run client in one terminal and npm run server in another terminal.
You can also use concurrently.
"scripts": {
"client": "cd client && npm start",
"server": "cd server && npm start",
"assets": "cd assets && ionic serve",
"start": "concurrently \"npm run client\" \"npm run server\" \"npm run assets\" ",
},
...
"devDependencies": {
"concurrently": "^1.0.0"
}