# Michael Tsai

> Michael Tsai is an indie Mac developer and the one-person operation behind C-Command Software, creator of SpamSieve - the gold-standard Bayesian spam filter for macOS that has been filtering email since 2002. He also runs one of the most respected daily link blogs in the Apple developer community, curating Mac and iOS developer news with original commentary since 2002. His roundups of community reaction to Apple events are so authoritative that Daring Fireball's John Gruber regularly links to them as the definitive overview.

- **Role:** Founder at C-Command Software
- **Organizations:** C-Command Software, ATPM (About This Particular Macintosh)
- **Nationality:** American
- **Education:** Computer Science, College (name unknown)
- **Known for:** SpamSieve rated highest among all anti-spam products in Macworld's 2003 cover story, Blog post about an Apple AI paper reached 150,000+ readers - biggest in newsletter history; adapted by The Guardian, Runs one of the most respected Apple developer link blogs since 2002 without advertising

## Career timeline

- **1995-1996** — Joined ATPM (About This Particular Macintosh) e-zine as reviews editor at age 16 (March 1996), then became co-publisher (June 1996)
- **2002** — Founded C-Command Software and launched SpamSieve, his Bayesian spam filter for macOS, inspired by Paul Graham's 'A Plan for Spam'
- **2002** — Launched mjtsai.com blog, which became a daily link blog covering Mac and Apple developer news
- **2003** — SpamSieve 1.2.2 received four mice in Macworld's anti-spam cover story - the highest rating among all competing products
- **2003** — John Gruber (Daring Fireball) published a long interview with Tsai, calling him one of his favorite bloggers and Mac developers
- **2018** — Acquired ToothFairy (Bluetooth menu-bar switcher) from original developer Robin Lu; launched Patreon for the blog
- **2021** — Wrote 'Bad AppleScript: Fake RSS, Real Newsletter' documenting his custom newsletter delivery system
- **2026** — Blog remains active with multiple posts per week; latest post April 24, 2026 covering Git Tower 16

## Achievements

- SpamSieve rated highest among all anti-spam products in Macworld's 2003 cover story
- Blog post about an Apple AI paper reached 150,000+ readers - biggest in newsletter history; adapted by The Guardian
- Runs one of the most respected Apple developer link blogs since 2002 without advertising
- John Gruber publicly encouraged Daring Fireball readers to support Tsai's Patreon in 2018
- Solo developer maintaining 4+ commercial Mac apps (SpamSieve, EagleFiler, DropDMG, ToothFairy)
- Co-published ATPM e-zine at age 16

## Latest updates

- **2026-04** — Blog post about Git Tower 16 published April 24, 2026 - blog remains highly active
- **2025-03** — Daring Fireball linked to Tsai's 'Something Is Rotten' roundup as a definitive community overview
- **2021-02** — Published 'Bad AppleScript: Fake RSS, Real Newsletter' describing custom newsletter infrastructure

## Links

- Website: https://mjtsai.com
- Twitter/X: https://x.com/mjtsai
- GitHub: https://github.com/michaeljtsai

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Profile page: https://yespress.io/michael-tsai
Published by YesPress — https://yespress.io
Last updated: 2026-04-25