Open source developer for MJML

Sinch is pioneering the way the world communicates. More than 150,000 businesses — including Google, Uber, Paypal, Visa, Tinder, and many others — rely on Sinch’s Customer Communications Cloud to power engaging customer experiences through mobile messaging, voice, and email.

Whether you need to verify users or craft omnichannel campaigns, Sinch makes it easy. Our AI-infused Super Network, APIs, and applications ensure you can connect with your customers reliably and securely, at every step of their journey.

At Sinch we “Dream Big”, “Win Together”, “Keep it simple”, and “Make it Happen”. These values are our foundation!

We’re looking for a skilled developer to take ownership of MJML (MailJet + htML) and lead its evolution. In this role, you’ll ensure the best email rendering across different inboxes while maintaining and improving our open-source front-end project, private API repository, and marketing site. You’ll represent Sinch in the MJML community, contributing to discussions on best practices and improvements. You’ll also play a key role in developing and enhancing MJML itself, ensuring it evolves to meet modern email development needs.

This is a fully remote role, based in France, reports to the Team Lead of Engineering, and offers a unique opportunity to lead email rendering efforts, contribute to open-source projects, and directly shape a widely used email framework.

Learn more about

Check out our open-source project:

• Develop and enhance MJML, shaping its evolution as a leading email templating framework.
• Improve email-building workflows by managing the open-source project and private API repository.
• Optimize and maintain the marketing website to align with branding and technical standards.
• Stay up to date with industry trends, and email client updates to continuously improve email rendering capabilities.
• Engage with the MJML community, contributing to discussions, and sharing insights.
• Implement best practices in email performance optimization, accessibility, and user experience.
• Ensure high email deliverability and responsiveness by understanding the nuances of different inbox rendering behaviors.

We believe you thrive in an independent role, taking initiative and solving challenges with confidence. As the go-to expert in this domain, you bring strong problem-solving skills and the ability to drive improvements proactively. Effective communication is essential, as you’ll engage with the MJML community and share insights on email rendering best practices. Versatility is key and you are comfortable working across frontend, backend, and APIs. A keen interest in email rendering trends and a commitment to staying ahead of industry developments will help you excel in this role.

• Expertise in MJML, HTML, and CSS, with a deep understanding of email rendering challenges across various inbox providers.
• Strong experience with Node.js (Express.js) and familiarity with Golang.
• Ability to optimize and troubleshoot email templates for different email clients (Gmail, Outlook, Apple Mail, etc.).
• Knowledge of email best practices, including accessibility, dark mode compatibility, and responsive design.

Our corporate language is English, please submit your application in English.

We are committed to ensuring a recruitment process that is fair, objective, consistent, and inclusive. Our approach includes structured, competency-based interviews designed to evaluate your skills, experience, and qualifications relevant to the role. At times, we may include a data-driven assessment to enhance our hiring success and identify candidates likely to excel.

We believe in a two-way process and encourage you to ask questions throughout the journey.  If this role isn't what you're looking for, please explore the other opportunities listed on our career page: No matter who you are, we hope you find an exciting path forward - hopefully with us!