This is quite easy, maile has a simple API endpoint at POST /api/send that allows sending simple transactional emails (think welcome emails, order notifications, etc) to any subscriber.
{
"subject": "Welcome to the show {{ user.name }}!",
"to": "[email protected]",
"from": "[email protected]",
"template": {
"id": "new-products-notification",
"data": {
"user": {
"name": "Gavin Belson",
"email": "[email protected]"
},
"products": [
{
"title": "Gilfoyle old servers",
"price": 99.00
},
{
"title": "Erlich old pants",
"price": 199.00
},
{
"title": "Jian-Yang hotdog or not application",
"price": 1000.00
}
]
}
},
"tracking": {
"opens": true,
"clicks": true
}
}