The address your customer sees
Customer mail leaves from the workspace’s own sender, and that takes one of two shapes. The default is shared: the workspace gets its own mailbox on a Mergelay sub-domain derived from its slug, which is unique by construction, so two workspaces can never be handed the same customer-facing address. Mergelay verifies that sub-domain once rather than once per customer, which is why there is no DNS step and why it works from your very first Update.
The other shape is a domain you own. On Team you verify it through DKIM and SPF, with Mergelay showing you the exact records to publish at your registrar. That is the address a recipient recognises, and it is the one that carries your own deliverability reputation rather than borrowing ours. Either way you choose the sender name and the reply-to; reply-to defaults to the workspace owner, because a customer answering a release note is answering a person.
At send time the resolution order is fixed and dull, which is the point: a verified custom domain if the plan allows one, otherwise the shared sub-domain. A downgrade destroys nothing — the verified domain and its published records stay on file, marked kept but inactive, and mail falls back to the shared address instead of failing. Only an explicit removal releases the registration.
How the email looks
The brand kit is off by default: a new workspace renders exactly what Mergelay sent before the kit existed. Turn it on and this is what you get.
- A display name, an accent colour and a logo
The logo is either a pasted https URL or an upload of at most 256 KB and 2000 px per edge, kept to PNG, JPEG and GIF sniffed from the actual bytes.
- No SVG, on purpose
In a logo slot an SVG is script that a mail client would be asked to run. That is a refusal we would rather explain than quietly allow.
- Alt text as a first-class field
A blocked image is the common case on a first open, so the words behind the logo are part of the design rather than an accessibility afterthought.
- One of three layouts
Plain, Letterhead or Banner, with optional header text, footer text and a single https footer link. It is a house style, not a page builder.
- A preview that is the send path
The preview renders through the same function that sends, so what it shows you is what lands — no separate template drifting quietly out of step.
- A brand snapshot pinned at preparation
Every Update pins the kit when it is prepared and sends from that snapshot, never from the live kit. Edit the kit afterwards and the Update reports itself as outdated until you adopt the change explicitly.
The kit is identical on both plans. What a plan changes is the address, not the appearance: Developer sends from the shared sub-domain and Team adds the domain you own.
Approving what customers will read
One approval covers all the enabled drafts and destinations of one exact revision, and any content edit creates a new revision that needs a fresh decision. There is no version of this where someone reads draft two and draft four reaches your list.
Because the reviewer is usually not sitting in the product when an Update becomes ready, Mergelay emails them a signed one-click review link. Its contract is deliberately narrow: valid for 72 hours, bound to one workspace, one Update and one named operator, and single-use for the decision — reading the drafts never spends it, and a stale-version conflict does not either. At the moment of approval it re-checks that the person is still an active owner or admin, so withdrawing someone’s membership also withdraws any link already sitting in their mailbox.
That link is a credential, and we say so rather than describing it as a convenience. Anyone holding it can approve the Update it names. The narrow scope, the expiry and the membership re-check are what make that trade-off defensible; the same statement appears on the security page, worded the same way.
What Mergelay does not do for customer email
The section that earns the trust the rest of this page spends. All four are true today.
- There is no hosted public changelog page. The release-note record is private Markdown you copy where you want it, or push to your own CMS or an automation webhook. If a permanent public URL per release is what you need, Mergelay is not the thing that gives it to you.
- There is no unsubscribe machinery: no preference centre, no suppression list, no List-Unsubscribe header. You remain responsible for who is on your list and for the law that applies to it, and you should read that sentence before you buy rather than after.
- One email destination carries at most 20 recipient addresses. That ceiling is platform-owned: workspace policy can lower it, and no browser, REST or coding-agent caller can raise it.
- With no mail provider key configured, a send lands in the local outbox flagged as simulated rather than being silently dropped. That is a deployment state, not a customer feature — but it is the difference between a visible gap and a message you believe went out.
Questions
Can I send from my own domain?
On Team, yes — one domain you own, verified with DKIM and SPF, with the exact records shown to you. On Developer, customer mail leaves from your workspace’s own mailbox on the shared Mergelay sub-domain, which needs no DNS step and works from the first Update. It is a numeric plan limit rather than a feature flag, so a future multi-domain tier is a number change.
Is there an unsubscribe link?
No, and we would rather tell you before you buy. There is no preference centre, no suppression list and no List-Unsubscribe header today. Mergelay is built for release communication to a list you already own and are already responsible for, not for marketing sends to a bought one.
Can I publish a public changelog page?
Not hosted by us. You get a private Markdown record to copy, or to push to your own CMS or an automation endpoint — n8n, Make, Zapier or something you wrote. Anything with a public URL is your surface, not ours.
How many people can one destination email?
20 addresses, and that is a ceiling rather than a plan feature: it does not rise on the more expensive plan. Larger lists belong in the tool that already owns them, reached through the automation webhook.
Where to read next
- Automated product updatesWhat runs without you, and the line customer publication never crosses.
- GitHub release notes generatorThe full pipeline, and the table of what leaves your repository.
- Privacy noticeWhat Mergelay stores, where, and for how long.
- PricingBoth plans, and what the plan actually changes.
Write the email your customers were waiting for.
Your first Update is free. No card required.