Mailend

Preview and diff emails before they reach users.

Mailend is a developer-first CLI tool to preview transactional emails across major clients, generate visual diffs, and produce offline reports for CI.

Why

Emails break in different clients. Bugs are noticed only after users complain. Marketing tools are heavy and expensive. Mailend gives developers a fast, simple way to preview and diff emails — before they go to production.

How it works

1. Run Mailend in CI or locally.
2. It renders your email in major clients.
3. It generates screenshots and visual diffs.
4. You get an offline report you can review or attach to a PR.

Who is it for

• Backend & full-stack developers
• QA engineers testing transactional emails
• Teams who want automated email regression tests