Cuttlefish
Open-source transactional email server with a web UI.
Cuttlefish is a self-hosted transactional email server with SMTP delivery, bounce handling, open and click tracking, real-time analytics, a web UI, and an API. It runs on top of Postfix and is explicitly positioned as free and open source software.
At an early stage the deciding factors are what the free tier actually covers, what the first paid invoice looks like, and how much of a founding engineer's week the setup costs. Feature depth that only matters at a million sends a month is noise until it is not.
Against a waitlist, a launch announcement, onboarding email, and the first transactional sends, Cuttlefish covers developer experience, and does not cover scheduling, SDK breadth, and webhook coverage. Whether that gap matters depends on how central those are to the build.
- Free tier: Free self-hosted, open source
- Best published rate per 1,000: Tiers not published in comparable form
- Starts at: Free self-hosted
- DX score: 6/10
- Deliverability: Self-hosted deliverability depends on Postfix configuration, IP reputation, DNS authentication, bounce processing, and list hygiene. Cuttlefish adds bounce suppression and analytics around SMTP delivery.
- Operating since: Not published
- Scheduling: No
- SDKs: None
- Webhooks: No
Self-hosted deliverability depends on Postfix configuration, IP reputation, DNS authentication, bounce processing, and list hygiene. Cuttlefish adds bounce suppression and analytics around SMTP delivery.
Teams that want a self-hosted transactional email dashboard in front of Postfix.
Teams that need managed deliverability, inbound parsing, or template tooling.
- › Open-source transactional email with a useful web UI
- › SMTP integration works with any framework or language
- › Bounce handling, open tracking, click tracking, and application-level analytics are built in
- › Project site describes the product as beta
- › Official site says it does not handle incoming email or built-in templates
- › Requires Postfix and self-hosted operations expertise
Features at a glance
| API | Yes |
| SMTP | Yes |
| SDKs | None |
| Webhooks | No |
| Templates | none |
| React Email | No |
| Batch send | No |
| Scheduled send | No |
| Suppressions | Yes |
| Multi-tenant | Yes |
| Inbound parsing | No |
| Event stream | Yes |
| Idempotency keys | No |
| Dedicated IP | No |