Nodemailer v4+ is licensed under the MIT license.
Version 3 of Nodemailer was licensed under the European Union Public License 1.1 (EUPL), which is a copyleft license. For more details on the decision to use EUPL for Nodemailer v3, you can refer to the Nodemailer blog. However, after a two-month experiment, I decided to revert Nodemailer back to the MIT license and canceled all active subscriptions.
Using a restrictive license for a lower-level infrastructure module like Nodemailer proved to be more problematic than beneficial. Even I had to use older versions of Nodemailer to avoid licensing issues for client work. Additionally, there wasn’t a significant interest in paid subscriptions or services, and most users continued using the copyleft-licensed Nodemailer in their commercial projects, with little concern for the licensing terms. Without a feasible way to enforce the copyleft license, the decision was made to return to the more permissive MIT license.
If you appreciate Nodemailer or if your business profits from its use, I would greatly appreciate any support. You can donate via Bitcoin or PayPal, or become a sponsor on GitHub.
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