#1
A Privacy-first, Cross-platform Text Expander written in Rust
14K starsJun 14, 2026 pushproductivity-automationRustProductivity
$ npx skills add espanso/espansoAlternatives
Postsack alternatives for AI agents.
Compare similar skills by workflow fit, trust score, quality, GitHub adoption, maintenance, and install readiness.
Current skill
Postsack
Visually cluster your emails by sender, domain, and more to identify waste
54
Quality
75
Trust
569
Stars
#2
Check if an email address exists without sending any email, written in Rust. Comes with a ⚙️ HTTP backend.
8.8K starsMar 17, 2026 pushproductivity-automationRustEmail
$ npx skills add reacherhq/check-if-email-exists#3
:postbox: Gmail desktop app for macOS, Windows & Linux (formerly Gmail Desktop)
1.0K starsJun 15, 2026 pushproductivity-automationTypeScriptEmail
$ npx skills add zoidsh/meru#4
Wavebox, the revolutionary and feature-rich Chromium browser that's built for productive working across Google Workspaces, Microsoft Teams, ClickUp, Monday, Atlassian, Asana, AirTable, Slack, and every other web app you use to get work done.
1.4K starsJun 15, 2026 pushproductivity-automationJavaScriptEmail
$ npx skills add wavebox/waveboxapp#5
a mailer library for Rust
2.2K starsJun 12, 2026 pushproductivity-automationRustEmail
$ npx skills add lettre/lettre#6
: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/Mailspring#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
CLI to manage emails
6.4K starsJun 12, 2026 pushproductivity-automationRustEmail
$ npx skills add pimalaya/himalaya#9
IMAP client library for Rust
575 starsJun 8, 2026 pushproductivity-automationRustEmail
$ npx skills add jonhoo/rust-imap#10
Email tracker, read receipt and spy pixel blocker plugin for macOS Mail (10.11-13.x)
1.1K starsMay 24, 2026 pushproductivity-automationObjective-CEmail
$ npx skills add apparition47/MailTrackerBlocker#11
An email framework that converts simple HTML into responsive email-ready HTML.
697 starsApr 24, 2026 pushproductivity-automationRustEmail
$ npx skills add foundation/inky#12
The classic email sending library for PHP
22K starsJun 6, 2026 pushproductivity-automationPHPEmail
$ npx skills add PHPMailer/PHPMailer#13
macOS command line tool for developers – The ultimate tool to manage your Mac. It provides a huge set of command line commands that automatize the usage of your Mac.
9.1K starsFeb 28, 2026 pushproductivity-automationShellProductivity
$ npx skills add guarinogabriel/Mac-CLI#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 Postsack if it already passes your workflow test and repository review.
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Open the compare page, test the install commands in a sandbox, and check each repository before using a skill in production.