Comparison

Sentroy vs Mailgun

Mailgun is a long-standing, high-volume managed mail platform. Sentroy is an open, self-hostable platform where mail is bundled with storage, auth, and env management. This page is an honest side-by-side so you can pick the right one — and a migration snippet if you decide to switch.

Quick comparison#

The five questions most teams care about when picking a transactional email vendor.

	Sentroy	Mailgun
Pricing model	Flat platform tier; send volume not metered per email	Per-email tiered (Foundation / Growth / Scale plans)
Self-hostable	Yes — Postfix/Dovecot/Rspamd stack ships as IaC	No — managed SaaS only
Open formats	MJML templates, raw MIME, IMAP-backed inbox	Handlebars templates, raw HTML, route receiver
Lock-in	Low — standards-based, exportable, self-host path	Moderate — proprietary API, region-locked dashboards
Bundled with other products	Storage + auth + env vault + status pages, one tenant	Email-focused (validate, inbox placement add-ons)

What is the same#

The places these two products meaningfully overlap.

Both expose REST APIs and SMTP for transactional send.
Both handle DKIM, SPF, and DMARC verification.
Both ship per-domain webhooks with HMAC-signed payloads.
Both support template variables, attachments, and bulk-friendly recipient arrays.
Both expose suppressions and bounce / complaint handling.
Both maintain a queryable mail log for delivery debugging.

What is different#

Honest differences in both directions.

Where Sentroy is different

Self-hostable end-to-end — the production Postfix/Dovecot/Rspamd stack is the same one shipped to operators.
Multilingual templates as a first-class field shape; no application-side locale switching needed.
IMAP-backed inbox API — read replies, list folders, mark-as-read, thread by subject, all from the same client.
Same access token reaches storage / auth / env vault — one credential, one billing line.
Flat platform pricing — high-volume bursts don't spike the bill.

Where Mailgun is different

Massive scale operator — petabyte-class send infrastructure across multiple regions.
Inbox placement and email validation services available as paid add-ons.
Email parsing "routes" for incoming mail handling — mature, well-documented.
EU and US regional accounts for data residency without self-hosting.
Longer track record on regulated industry compliance (HIPAA BAAs, etc.).

When to pick Sentroy#

Concrete situations where Sentroy is the better call.

You want a bundled platform — email plus storage, auth, and config — instead of stitching four vendors.
You ship multilingual transactional email and want translations inside the template, not your app.
Your ops team wants the option to self-host the entire mail stack on infrastructure you control.
You need an inbox API for replies, not just a send API — support / reply-flow products benefit.

When to stick with Mailgun#

Cases where staying on Mailgun is the right call.

You send millions of emails per day and need a vendor with proven multi-region throughput at that scale.
You depend on Mailgun's validation or inbox-placement add-ons that don't have a 1:1 equivalent yet.
You have a signed HIPAA BAA or a long-standing reputation IP pool you don't want to migrate.

Migration#

One operation, both APIs side by side.

Sending a transactional email with template variables:

before.ts — Mailgunts

import formData from "form-data"
import Mailgun from "mailgun.js"

const mailgun = new Mailgun(formData)
const mg = mailgun.client({ username: "api", key: process.env.MAILGUN_API_KEY! })

await mg.messages.create("acme.dev", {
  from: "Acme <onboarding@acme.dev>",
  to: "user@example.com",
  subject: "Welcome to Acme",
  template: "welcome",
  "h:X-Mailgun-Variables": JSON.stringify({ name: "Jane" }),
})

after.ts — Sentroyts

import { Sentroy } from "@sentroy-co/client-sdk"

const sentroy = new Sentroy({
  baseUrl: "https://sentroy.com",
  companySlug: "acme",
  accessToken: process.env.SENTROY_ACCESS_TOKEN!,
})

await sentroy.send.email({
  from: "onboarding@acme.dev",
  to: "user@example.com",
  subject: "Welcome to Acme",
  domainId: "<acme-domain-id>",
  templateId: "<welcome-template-id>",
  variables: { name: "Jane" },
})

Mailgun's h:X-Mailgun-Variables header becomes a typed variables object on Sentroy; both feed the same template substitution at send time.

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