#1
:love_letter: A beautiful, fast and fully open source mail client for Mac, Windows and Linux.
18K starsJun 15, 2026 pushproductivity-automationJavaScriptEmail
$ npx skills add Foundry376/MailspringAlternatives
Sieve alternatives for AI agents.
Compare similar skills by workflow fit, trust score, quality, GitHub adoption, maintenance, and install readiness.
Current skill
Sieve
Sieve Script Editor
87
Quality
86
Trust
882
Stars
#2
MJML: the only framework that makes responsive-email easy
18K starsJun 12, 2026 pushproductivity-automationJavaScriptEmail
$ npx skills add mjmlio/mjml#3
A Cloudflare-based email service | 基于 Cloudflare 的邮箱服务 | Cloudflare Email 邮箱 Mail
11K starsJun 9, 2026 pushproductivity-automationJavaScriptEmail
$ npx skills add maillab/cloud-mail#4
✉️ Send e-mails with Node.JS – easy as cake!
18K starsJun 15, 2026 pushproductivity-automationJavaScriptEmail
$ npx skills add nodemailer/nodemailer#5
a list of disposable email domains
5.1K starsJun 16, 2026 pushproductivity-automationPythonEmail
$ npx skills add disposable-email-domains/disposable-email-domains#6
Open YouTube / Video browser-extension [top~1] Enrich your experience&choice!🧰Smart features📌set&forget📌250+tweaks - Longest-standing. Join🧩us?👨👩👧👧 ⋮ {playback|discovery|extra player buttons|quality|codec|full tab|full screen|no distraction|shorts}
4.4K starsJun 12, 2026 pushproductivity-automationJavaScriptProductivity
$ npx skills add code-charity/youtube#7
:love_letter: An extensible desktop mail app built on the modern web. Forks welcome!
25K starsNov 24, 2022 pushproductivity-automationJavaScriptProductivity
$ npx skills add nylas/nylas-mail#8
Decentralized private messenger with chat-shared tools and games for Desktop
1.5K starsJun 16, 2026 pushproductivity-automationTypeScriptEmail
$ npx skills add deltachat/deltachat-desktop#9
Juice inlines CSS stylesheets into your HTML source.
3.3K starsJun 15, 2026 pushproductivity-automationJavaScriptEmail
$ npx skills add Automattic/juice#10
:postbox: Gmail desktop app for macOS, Windows & Linux (formerly Gmail Desktop)
1.0K starsJun 15, 2026 pushproductivity-automationTypeScriptEmail
$ npx skills add zoidsh/meru#11
The Official Twilio SendGrid Led, Community Driven Node.js API Library
3.1K starsMay 31, 2026 pushproductivity-automationJavaScriptEmail
$ npx skills add sendgrid/sendgrid-nodejs#12
JavaScript plugin for finding links in plain-text and converting them to HTML <a> tags.
2.0K starsJun 15, 2026 pushproductivity-automationJavaScriptEmail
$ npx skills add nfrasser/linkifyjs#13
The classic email sending library for PHP
22K starsJun 6, 2026 pushproductivity-automationPHPEmail
$ npx skills add PHPMailer/PHPMailer#14
The open-source communication infrastructure for agents and products
39K starsJun 16, 2026 pushproductivity-automationTypeScriptEmail
$ npx skills add novuhq/novu#15
Mail-in-a-Box helps individuals take back control of their email by defining a one-click, easy-to-deploy SMTP+everything else server: a mail server in a box.
15K starsMay 24, 2026 pushproductivity-automationPythonEmail
$ npx skills add mail-in-a-box/mailinabox#16
BillionMail gives you open-source MailServer, NewsLetter, Email Marketing — fully self-hosted, dev-friendly, and free from monthly fees. Join the discord: https://discord.gg/asfXzBUhZr
15K starsJun 11, 2026 pushproductivity-automationGoEmail
$ npx skills add Billionmail/BillionMailHow to choose
When should you switch?
Use an alternative when it has a clearer install path, higher trust score, fresher maintenance, or better platform fit for your current agent stack. Keep Sieve if it already passes your workflow test and repository review.
Next step
Compare top candidates side by side
Open the compare page, test the install commands in a sandbox, and check each repository before using a skill in production.