Open source by the makers of EmailEngine
Cloudflare, Resend, Elastic, Mozilla and n8n ship Nodemailer, postal-mime and ImapFlow in their own products. EmailEngine is built on the same libraries, by the same developer.
A dozen of the products that list our libraries as a dependency.
Cloudflare
A dependency of the Agents SDK for building AI agents on Workers, and bundled into Miniflare, the local runtime behind wrangler dev.
Source: Agents SDK, Agentic Inbox, Miniflare
Resend
A runtime dependency of resend, the official Node.js package for the Resend email API.
Source: resend-node
Elastic
A dependency of Kibana, the user interface of the Elastic Stack.
Source: kibana
Mozilla
In the authentication server behind Mozilla accounts, and in Mozilla Monitor, the data breach alert service.
Source: fxa-auth-server, blurts-server
Firebase
The official Firebase extension for sending email from Cloud Firestore.
Source: firestore-send-email
Vercel
The Gmail adapter of Vercel's Chat SDK, a universal chat layer for building bots and agents.
Source: adapter-gmail
WordPress
A dependency of WordPress Playground, which runs WordPress entirely in the browser.
Source: wordpress-playground
Backstage
The email channel of Backstage notifications, in the developer portal framework created at Spotify.
n8n
In the IMAP trigger and the email nodes of the workflow automation platform.
Source: @n8n/imap, nodes-base
Tuta
A dependency of the client for Tuta's end-to-end encrypted email service.
Source: tutanota
Microsoft
In the portal Microsoft uses to manage its open source on GitHub, and in TypeAgent, sample code for building a personal AI agent.
Source: opensource-management-portal, TypeAgent
Twilio SendGrid
A dependency of SendGrid's official Node.js package for parsing inbound email webhooks.
Source: inbound-mail-parser
Pick a library to see who depends on it. Each name opens the file that lists it.
Sends email from Node.js, over SMTP or through a transport plugin.
16M+ downloads a week
Inside EmailEngine
Parses email in browsers, Web Workers and serverless runtimes such as Cloudflare Workers.
10M+ downloads a week
A modern IMAP client for Node.js, with a promise-based API and IDLE support.
2M+ downloads a week
Inside EmailEngine
A streaming parser for Node.js that turns raw email into text, HTML, headers and attachments.
5M+ downloads a week
Inside EmailEngine
Builds SMTP and LMTP servers in Node.js, for receiving mail or testing sending.
400K+ downloads a week
Inside EmailEngine
Email authentication for Node.js: SPF, DKIM, DMARC, ARC and BIMI.
600K+ downloads a week
Standards bodies, research centres and government digital services.
W3C
Echidna, the W3C's automated publishing pipeline for specifications.
NASA
mEditor, the metadata editor NASA's Goddard Earth Sciences data center uses to manage its data holdings.
Government of British Columbia
NotifyBC, a notification service, using Nodemailer and Mailparser.
U.S. General Services Administration
GEAR, the GSA's Enterprise Architecture Reporting portal.
French government
DomiFa and the aides-jeunes benefits simulator, digital services of the social affairs ministries.
Berkman Klein Center, Harvard
email-auth, an email header verification tool, using mailauth.
package.json on its default branch in October 2026, and each name links to that file.EmailEngine runs ImapFlow, Nodemailer and Mailparser behind one REST API and webhooks for Gmail, Microsoft 365 and IMAP accounts, on your own servers.