Lettre by lettre
a mailer library for Rust
About Lettre
From the project's README at github.com/lettre/lettre. Lightly cleaned for readability; for the full source see the upstream repo.
Multiple transport methods Unicode support (for email content and addresses) Secure delivery with SMTP using encryption and authentication Easy email builders Async support
Lettre supports all Rust versions released in the last 6 months. At the time of writing the minimum supported Rust version is 1.74, but this could change at any time either from one of our dependencies bumping their MSRV or by a new patch release of lettre. Example
Health score breakdown
6-dimension composite. See methodology for formula and weights.
Adoption signals
Real-world usage data, pulled from each registry. The bigger the numbers, the more battle-tested the project.
| Signal | Value | Source |
|---|---|---|
| GitHub stars | 2.2k | github.com/lettre/lettre |
| GitHub forks | 222 | github.com/lettre/lettre |
| CRATES downloads (last month) | 2740k | lettre |
Release & maintenance
Is this project actively maintained, or about to die? Check the recency of last commit and last release.
| Project age | 12.3 years | since Feb 2014 |
| Last commit | 13 days ago | Apr 24, 2026 |
| Releases shipped | 29 | last: 1 months ago |
| Security policy | SECURITY.md | declared by maintainers |
| Funding links | 1 | declared by maintainers |
Self-hosting cost across providers
Detected requirements: 4GB RAM, 40GB disk minimum. Cheapest plan per provider that meets the requirement.
| Provider | Plan | Specs | Monthly | |
|---|---|---|---|---|
| hetzner | CAX11 | 2c · 4GB · 40GB | $4.13 USD | Deploy → |
| vultr | VC2 | 1c · 1GB · 25GB | $5 USD | Deploy → |
| linode | Nanode 1GB | 1c · 1GB · 25GB | $5.12 USD | Deploy → |
| digitalocean | Basic Regular 1GB | 1c · 1GB · 25GB | $6 USD | Deploy → |
Security advisories
GHSA-vc2p-r46x-m3vx. What people say on Hacker News
Ready to self-host Lettre?
Spin up a hetzner CAX11 (4GB RAM, 40GB disk) for $4.13/mo and follow the project's official install docs.
Data last refreshed May 7, 2026.
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