Senlo

Judgement

What it is

Complete system

What it does

Self-hosted infrastructure for building, managing and sending transactional and lifecycle emails through providers like SES, Mailgun and Postmark, with an MJML template editor.

Adopt it when

A product team wants its email templates and sending logic in its own system rather than in a vendor's dashboard.

Watch out

Ten months old, no releases, and AGPL licensed.

Ready for

Experimental

Runs as

Self-hosted server

Built with

TypeScript and MJML

How established

Young: started 10 months ago, no tagged release yet.

What the license allows

Use inside your business is unrestricted. If you change it and let customers use it over the internet, you must publish your changes.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Senlo → TypeScript → Go → runs on a microchip

How compilers were built, back to punched paper tape

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