Catapulte

Judgement

What it is

Complete system

What it does

An email sending service in Rust that accepts plain, HTML or MJML messages over an API, renders templates and delivers through SMTP, with message status and lifecycle events.

Adopt it when

You want a small self-hosted service that renders MJML templates and sends them for your apps.

Watch out

One maintainer and AGPL licensing; releases are per-component and still early.

Ready for

Usable

Runs as

Self-hosted server

Built with

Rust, Axum, SQLx and Tokio

How established

Established: started 6 years ago, latest release catapulte-adapter-template-v0.1.0.

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: Catapulte → Rust → runs on a microchip

How compilers were built, back to punched paper tape

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