# voidlabs/mosaico

Mosaico - Responsive Email Template Editor

Repository: https://github.com/voidlabs/mosaico
Canonical: https://ross.abutalabs.com/products/mosaico
Homepage: https://mosaico.io
Language: HTML
License: GPL-3.0
License Family: copyleft
Topics: email-marketing, email-template, email, builder, knockout, javascript
Last push: 2025-08-22T11:37:23+00:00

## Health v2 (maintenance only)
Score: 41/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 38, release rhythm 12, longevity 100
- inputs: {"age_days": 4108, "days_push": 376, "days_rel": 376, "gap_med": null, "n_releases_24m": 1}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1781, forks 503 (observed 2026-08-28T04:05:35.581444+00:00)

## What it is
Mosaico is an open-source JavaScript library/single-page application for visually editing responsive email templates via drag and drop. Editable content and styles are defined by the template itself using a simple template language, making the editor highly flexible.

## Use cases
- build a drag-and-drop email template editor into my app
- let non-technical users customize responsive email newsletters
- edit email HTML templates that work across email clients
- embed an email builder in a newsletter platform
- create customizable email templates with a template language
- self-host an open-source email designer

## When to choose
- you need users to visually edit email templates without touching HTML
- you want template-driven control over what is editable
- you're building a newsletter or email marketing tool and need an editor component
- you need responsive email output tested across major email clients

## When to avoid
- you need a full email sending or campaign management platform (pair it with e.g. MailTrain)
- you want a generic web page or landing page builder rather than email
- you need a maintained commercial-grade editor with vendor support
- your stack can't integrate a JavaScript SPA or provide a backend for image upload/storage

## Facets
- artifact type: library
- maturity: maintenance
- function: templating, ui-components, frontend-framework, email
- domain: email, web-development, frontend, cms
- platform: browser
- tags: email-template-editor, drag-and-drop, responsive-email, email-marketing, wysiwyg, knockoutjs, single-page-application, web-server, nodejs, docker, javascript

## Member repositories
- voidlabs/mosaico (main) score 41

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:05:35.581444+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T03:24:26.047465+00:00, confidence not recorded.
  - readme: https://github.com/voidlabs/mosaico (fetched 2026-08-28T04:05:35.581444+00:00, sha 7ef0d3aef89c)
  - homepage: https://mosaico.io (fetched 2026-08-29T11:03:06.917159+00:00, sha 89c2beff6c3b)
- Data as of 2026-08-30T08:39:29.467469+00:00.