Outsend and Plunk
Plunk is an open-source email platform with transactional mail, campaigns, and visual workflow automation in one place. Outsend is narrower, and goes deeper on the evidence behind each send.
Open source, and you can run it yourself
Plunk is AGPL-3.0 and self-hostable with Docker on your own AWS account. If you need to own the deployment, Plunk meets that requirement and we do not.
Workflow automation built in
A visual builder with triggers, delays, and conditional logic, no code required. If drip sequences and event-driven journeys are central to what you send, Plunk does more of that than we do.
Inbound email
Plunk can process incoming mail and notify you by webhook. We only send, so if receiving mail is part of the job, Plunk does something we do not.
Events keep the provider's raw payload
Every event stores the receiving provider's original response alongside our normalised version, so you can see exactly why a message bounced or was deferred rather than reading our summary of it.
One bad domain cannot sink the others
Each domain carries its own reputation score. If one starts collecting complaints, its sending pauses on its own while your other domains keep going, and a new domain starts slow and ramps up.
An MCP server and a CLI
Coding agents and scripts get the same evidence a person sees in the dashboard. An agent can send a message, pull its trace, and tell you why it bounced, without anyone opening a browser.
If you want to self-host, or automation workflows are the core of your email, choose Plunk. If you want the provider's own evidence behind every message and reputation that is isolated per domain, try Outsend.
We quote competitor prices in one place only. The price calculator shows each one with its source and the date we checked it. Confirm it on Plunk's pricing page before you decide.
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Switching from Plunk?
The quickstart has you verified, sending, and reading a real trace in about ten minutes.
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