"How to Send Bulk Emails With Spring Boot and Twilio" summary:` Sending bulk emails with Spring Boot and Twilio is a powerful way to reach and engage a wide audience. This tutorial demonstrated three approaches to sending bulk emails using the Twilio SendGrid Email API in Java, including sending single emails many times, sending multiple emails in parallel, and sending a single email to multiple recipients through personalization. Each approach has its own set of challenges and limitations, but they can be used to implement efficient email sending solutions for various use cases. By leveraging Spring Boot's robust framework and Twilio's SendGrid Email API, developers can create scalable and reliable APIs to send bulk emails in a matter of lines of code.