Email

Nodemailer17.7k★

Nodemailer is the standard library for sending emails from Node.js. It's been the standard for sending email in Node.js for over a decade. Completely free under a permissive license. You get SMTP support, OAuth2 authentication, HTML and plain text emails, attachments, embedded images, DKIM signing, and connection pooling. It works with any SMTP server: Gmail, SendGrid, Mailgun, Amazon SES, your own Postfix server, whatever. No paid tier, no hosted service. It's a library. You install it, configure your SMTP credentials, and send emails. Everyone building Node.js apps that send email: use Nodemailer as your transport layer. Pair it with an ESP (email service provider) for deliverability. If you're sending marketing emails or newsletters, use a dedicated platform instead. The catch: Nodemailer sends emails. That's it. It doesn't manage email templates, track opens/clicks, handle unsubscribes, or give you analytics. For those, you need a service like Resend, SendGrid, or Mailgun on top. Also, sending emails reliably at scale (deliverability, reputation management, bounce handling) is a whole discipline that Nodemailer doesn't solve. It just sends.

Postal16.8k★

Postal is a self-hosted mail delivery platform for transactional email: password resets, order confirmations, notifications, all on infrastructure you own instead of paying per email through SendGrid. You run your own email server, control your sending reputation, and pay nothing per message. MIT license, Ruby. Full-featured: SMTP server, HTTP API, webhook delivery tracking, click/open tracking, bounce handling, multiple organizations and mail servers, IP pool management. Web UI included for monitoring and configuration. Fully free to self-host. No paid tier. Your costs are infrastructure: a VPS ($10-20/mo), a dedicated IP with clean reputation, and the time to set up DNS records (SPF, DKIM, DMARC). Solo developers sending a few hundred emails/month: overkill. Use Resend's free tier. Small teams sending thousands/month: Postal starts making financial sense when you'd otherwise spend $50-100/mo on an ESP. Medium to large orgs sending 100K+/month: Postal pays for itself quickly: at $0.001/email on SendGrid, 100K emails is $100/mo. Postal costs you a $20 VPS. The catch: email deliverability is hard. Running your own mail server means YOU are responsible for IP reputation, authentication records, warming up IPs, handling bounces correctly, and staying off blacklists. Get any of it wrong and your emails land in spam. This is not a 'set and forget' system. Budget 4-8 hours/month of ops minimum.

fx-private-relay1.8k★

Private Relay is Mozilla's email alias service: give every website a generated address that forwards to your real inbox, and when one starts spamming you, kill it. When an alias leaks, you know exactly who sold you out. The hosted service includes five free aliases, and the code behind it is open source under MPL 2.0. Self-hosting is technically possible and practically beside the point. It's a Django app that needs Postgres and Amazon SES, plus a sending domain with a solid mail reputation, which is the hard part of any email product. Almost everyone should use Mozilla's hosted service. Solo users: the free tier plus the browser extension covers the accounts that matter. Premium unlocks unlimited aliases and a custom domain for a few dollars a month. addy.io and SimpleLogin do the same job and are worth comparing before you commit. The catch: aliases forward mail, they don't host it. You're layering Mozilla's relay between you and every service you sign up for, and if you ever leave, updating hundreds of accounts is the exit cost.

james-project1.0k★

Apache James is a mail server you can program. SMTP, IMAP, POP3, and JMAP work out of the box, but the point is the mailet framework: drop your own Java classes into the processing pipeline and route, filter, or transform every message with custom logic. All of it is free under Apache 2.0, from a foundation project that has been at this for two decades. Running it is a real commitment. The simple setup (one JVM with local storage) is manageable, but the distributed flavor wants Cassandra, OpenSearch, S3-compatible storage, and RabbitMQ before it says hello. Then add the usual self-hosted email tax: reverse DNS, SPF, DKIM, DMARC, and IP reputation are all your problem. This is infrastructure work, not a weekend Docker project. Use James when email is part of the product: you're building mail handling into a platform, or you need processing rules a normal mail server can't express. Teams that just want mailboxes should pay Google Workspace or Fastmail and move on. For self-hosted sending without the Java, Postal is the better fit. The catch: James is a toolkit wearing a server costume. The docs assume Java fluency, the community is small next to mainstream mail stacks, and every custom mailet you write is code you maintain forever.