Which stack for weekly summary emails (i.e. Google Alerts)?

Think something like shown on the screenshot: Indeed.com's "Be the first to see new software engineer jobs in New York, NY" or Google Alerts.

Not sure if this classifies as transactional E-Mail, but I'm definitely not asking about marketing emails / newsletters.

Instinctively I would go for a custom setup where I create one serverless function per search alert (defined as a combination of search query and user) for aggregating the search result data and then use something like SendGrid, SES or Mailchimp to send the actual E-Mail.

Ideally I would like to abstract the first part (serverless function) away even further, to minimize development overhead.

Do you use or know of any SaaS tools that could help with this?