Plunk gathers in one tool what you pay Mailchimp or Brevo for. You send a newsletter to your whole list with the editor and templates, set up automations (a welcome email on signup, a sequence after an action), and your site or app sends its transactional emails through a simple API. Contacts, segments and history stay on your server, with no contact cap and no logo forced into your emails. The install uses Docker Compose, a Postgres database and a Redis. AGPL-3.0 license. The cloud version includes 1,000 free emails a month, then charges per email sent. Worth knowing: Plunk does not send by itself, it goes through Amazon SES, which charges about 9 cents per thousand emails. So you need an AWS account with your verified domain.
Versus Mailchimp: the match
Price
Plunk
€0, plus a small VPS and about 9 cents per thousand emails at Amazon
Mailchimp
€12 a month for 500 contacts, then by tier
Contacts
Plunk
No limit
Mailchimp
500 on Essentials, the price climbs with the list
Logo in your emails
Plunk
None
Mailchimp
Present on free, €9 more at Brevo to remove it
| VS | Plunk | Mailchimp ↗ |
|---|---|---|
| Price | €0, plus a small VPS and about 9 cents per thousand emails at Amazon | €12 a month for 500 contacts, then by tier |
| Contacts | No limit | 500 on Essentials, the price climbs with the list |
| Logo in your emails | None | Present on free, €9 more at Brevo to remove it |
| Transactional emails | Included, by API | Separate service, billed separately |
| Where your contacts live | On your server | With them |
| Deliverability | Up to you: SPF, DKIM and Amazon SES | Handled by them, it is their job |
How to install it (even from zero)
An AWS account with your domain verified in Amazon SES, a server, a domain name. The prompt installs Plunk with Docker Compose and sends a first email. Count thirty minutes, half of it at AWS.
- 1
Paste this prompt into Claude (Code or Desktop)
It walks you through Amazon SES, deploys Plunk from the official project with Docker Compose and checks a first send:
Installe Plunk sur mon serveur (la plateforme email open source, alternative à Mailchimp et Brevo, repo GitHub useplunk/plunk, image Docker driaug/plunk) en suivant la doc officielle docs.useplunk.com/self-hosting/introduction. Pars de zéro : vérifie que Docker et Docker Compose sont présents, sinon installe-les. Commence par Amazon SES : explique-moi comment créer un compte AWS, vérifier mon nom de domaine dans SES (enregistrements DNS DKIM et SPF à poser), créer un configuration set, demander la sortie du mode bac à sable pour envoyer à n'importe qui, et créer une clé d'accès IAM limitée à SES. Ensuite récupère le docker-compose.yml officiel de la doc, crée le fichier .env avec un JWT_SECRET long et aléatoire, les URL de mon tableau de bord et de mon API sur deux sous-domaines (app. et api.), la base Postgres et le Redis du compose, la région et les clés SES, et DISABLE_SIGNUPS à true dès que mon compte est créé. Mets un reverse proxy Caddy devant qui sert les deux sous-domaines en HTTPS avec certificats automatiques, sans publier les ports du conteneur. Lance le tout, crée mon compte, ajoute mon domaine d'envoi, puis envoie un mail de test à mon adresse depuis une campagne et un autre depuis l'API. Explique chaque étape simplement, je débute. Review the GitHub repository and check whether it is safe to install given my machine and my infrastructure. Ask me as many questions as possible, using widgets, to clarify my request and be as precise as you can.
- 2
Import your list and set your first automation
A CSV from Mailchimp or Brevo, then a “signup” event that triggers your welcome email. That is where you gain the most.
- 3
Warm up your domain before the big campaign
At Amazon, your reputation starts from zero. Send to your most active contacts first, in small volumes, before writing to the whole list.
Paste this prompt into Claude (Code or Desktop)What you actually do with it
Your newsletter, with no contact cap
You write in the editor, pick a segment, send. At 5,000 or 50,000 subscribers, the price does not move, only Amazon counts the emails.
The automatic welcome email
Someone leaves their address on your site or through Manychat, your site sends the event to Plunk, the sequence goes out by itself.
Your app's or shop's emails
Confirmation, invoice, login code: one API call and the email goes out, with the same domain and tracking as your campaigns.
Project health, at a glance
Before installing an open-source tool, one question matters: is the project alive? These scores are computed from public GitHub data. They are not made up.
90/100
ExcellentVery active, well-maintained project: go ahead with confidence.
- Activity
- 100
Is the code moving? (commits in the last 30 days)
- Maintenance
- 100
How fresh is the latest update? Fresher is better.
- Community
- 71
Stars and contributors: people around means help and fixes.
- Maturity
- 80
Project age. Old enough to be solid, still alive.
- Momentum
- 100
Current pace versus its usual pace: speeding up or dozing off?
The repo in numbers
- GitHub stars
- 5.5k
- Forks
- 425
- Contributors
- 55
- Commits
- 1.1k
- Project age
- 2.3 yrs
- Last commit
- 7 d ago
- Size
- 10 MB
- License
- AGPL-3.0
Built with
- TypeScript 93.8%
- MDX 5.1%
Scores computed automatically from the GitHub API (last-30-days activity, update freshness, community size, project age). Refreshed daily.
Loucash’s take
7/10
Let me say it upfront: this library runs on Brevo, and I have not migrated yet. Plunk is still the right alternative if you pay Mailchimp or Brevo for your list: campaigns, automations and transactional emails in one place, unlimited contacts, no forced logo, and everything stays with you. The API is simple, the dashboard is clean. What you have to accept: Plunk cannot send without Amazon SES. You need an AWS account, your verified domain, a request to leave the sandbox, and you carry the sending reputation. Mailchimp and Brevo, you mostly pay them for that, deliverability handled by people whose job it is. If your list is small or your sends rare, the price gap is not worth the time spent at AWS. My math: from a few thousand contacts and one send a week, Plunk saves you several tens of euros a month for a few cents at Amazon. That is when I will switch.
It’s for you if: You pay Mailchimp or Brevo for a list of several thousand contacts, you have a server, and you accept to spend half an hour at Amazon SES.
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