Transactional Email Templates by Postmark - Open source email templates for use in your SaaS app.
Liramail - Design your brand emails within minutes with Liramail Editor
Smart Templates by Sarbacane - Get customized email marketing templates from a URL 💌
EvaWarm - MAXIMIZE EMAIL DELIVERABILITY WITH A MANUAL WARMUP TO INCREASE YOUR OPEN RATE
MJML - The open source framework for responsive emails
HTMLEmail.io - Responsive HTML email templates for startups & developers