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My name is Jeremy Chadwick, otherwise known as koitsu, k9, or (more famously) Y0SHi/Yoshi. I've done lots of things, just like every other human.


Parodius Networking

I ran Parodius Networking, a free web/shell/mail/etc. hosting service, for about 18 years. We closed our doors on August 2012. We hosted numerous emulation, console, and romhacking websites, such as:

  • nesdev (NES/Famicom console development)
  • NES World (NES/Famicom fan site)
  • Donut/The Whirlpool (major romhacking hub) (R.I.P.)
  • Archaic Ruins (emulation news site) (R.I.P.)
  • NESticle (NES/Famicom emulator) (R.I.P.)
  • Genecyst (Genesis/Megadrive emulator) (R.I.P.)
  • Joy Electric (analog synth-pop band)

I've tried to take photos of our co-location cages over the years.

Console development / homebrew

  • Author of public-domain SNES documentation during the early-to-mid 90s.
  • Author of public-domain NES documentation, a.k.a. nestech.txt, during the late 90s into the early 21st century.
  • Author of the replacement Final Fantasy 2 intro for Neo Demiforce's English translation.
    • In March 2015, I decided to re-do the intro code, comment it, and make it public (in hopes of it being good learning material), along with a "why/how" write-up. I've finished the revamped code, but not the write-up. I'll release it when everything is polished.
      • As of November 2016, I still haven't gotten around to doing this.
  • Author of TRaCER, a 6502/65816 disassembler for MS-DOS, written in Turbo Pascal. And yes I'm aware of a bug in its 65816 opcode table.  :-(
  • Author/co-author of two MS-DOS NES emulators: VeNES (Turbo Pascal/x86 assembly) and qNES (x86 assembly).
    • VeNES got released publicly by Mr. Snazz (author/co-author) many years ago, but his site has since gone down. It was able to emulate NROM/mapper 0 games like Donkey Kong, Donkey Kong Jr., Mario Bros, Pinball, Popeye, and Tennis.
    • qNES was never released publicly or privately. It remained in development by Riff (Mike Perry) and myself for many years before I ended the project. All I remember is that we had finished the 6502 core and very basic PPU emulation, and had just begun implementing the VGA routines (256x256x256).
  • Still actively doing NES/SNES romhacking projects of my own, including a bunch of work on Otogirisou.


  • FreeBSD community member from 1997 to 2008.
    • I still use FreeBSD but I do not participate in the community any longer.[1]
    • I still report lots of bugs though.[2][3]
    • I keep an archive of random things I've dealt with or fixed on FreeBSD.
  • Ex-FreeBSD ports committer.
  • Author of bsdhwmon, an open source SMBus-focused hardware monitoring utility for FreeBSD.

Tomato firmware


  • Fixing up other people's stuff by submitting pull requests or filing GitHub issues.
  • Strong advocate of KISS principle and minimalism, both personally and professionally.
  • Working with storage subsystems, particularly ATA/SATA (including protocol and SMART), and doing reliable software-based data recovery.
  • Publicized several flaws with Logitech products, especially USB mice.
    • At least one employee at Logitech definitely did not like this, and threatened to talk to their legal department.
  • Was in an Apple IIGS demo group called Digital Exodus back in the early 90s. We released some useful CDAs (ex. DOCVu) and a Christmas demo in 1993.
  • Was in a console/"hacking" group called Damaged Cybernetics in the mid-90s. I'm still not exactly sure why; it was very odd/surreal, but fun at times too.
  • Was a news poster for Zophar's Domain during the "emulation peak" in the late 90s.


  • Why I still run Windows XP in 2015 — highly detailed. If only Microsoft listened... :-(
    • Update: since roughly April 2015, I've grudgingly upgraded to Windows 7 Ultimate SP1 x64.
  • Why I stopped doing nesdev for almost a decade (the related nesdev forum thread).
  • A bit egocentric, but: I still wonder why nobody has ever gotten around to interviewing me about either Parodius Networking or my role in emulation and/or console development.
    • On the flip side, The New 8-Bit Heroes folks did an in-person interview with me in March 2015 about my NES documentation and homebrew efforts.
      • As of November 2016, it doesn't look like any of the footage with me will be used. I'm bummed about this.
    • In May 2015, MIT Press published Nathan Altice's book titled I AM ERROR, in which my aforementioned NES documentation and emulator efforts are cited as references. I'll admit it's kinda weird seeing your name in published print.


  • I was born January 1977.
  • I'm originally from Oregon but presently reside in California (Silicon Valley).
  • The first programming language I ever used was Logo on an original Apple II. I enjoyed it, but really took to Applesoft BASIC shortly thereafter. I started doing 6502 assembly/machine language in 7th grade (1988 or so?), and then 65816 once I got my own Apple IIGS. I've done lots of other assembly over the years (ex. 6810, PIC16c84, x86/486), but enjoy the 65xxx series CPUs the most.
  • I'm somewhat of a polyglot/omniglot. I studied Mandarin for 4 years (high school) and about 6 months outside of school. I can read/write/speak Korean (maybe 1st or 2nd grade level), but lack vocabulary and grammar. I know several details of and phrases in Japanese, Russian, Tagalog, and even dabbled a bit in Afrikaans. I could at one point "tolerably" comprehend some Swedish as a result of playing in a Swedish World of Warcraft guild for about a year and having several Swedish friends.
  • For transporation, I ride a mountain bike; I don't drive (by choice).
  • I don't vote (by choice); I have no political affiliations, though I am a registered independent (though inactive) in the state of Oregon.
  • I like all kinds of music (you will find Iron Maiden next to Henson Cargill next to Lionel Ritchie next to De Lyckliga Kompisarna next to Carpenter Brut).
  • I'm an avid fan of the horror genre (movies, books, whatever); I absolutely adore H.P. Lovecraft.
  • Since 2001 I've had moderate-to-severe IBS and experience some form of its effects on a daily basis.
    • I only mention this because IBS has significantly impacted my life (in a very negative way) and helps explain both some parts of my behaviour (maybe even personality?) and how I live my life the way I do.
    • Partially as a result of my condition, my weight has fluctuated wildly over several years (maximum being 195 pounds, lowest being 140 pounds; I'm 5 foot 9 inches). I felt my best at around 165, but that was also when I was working out every other day.



  1. Why I left the FreeBSD Project:
  2. FreeBSD PRs for
  3. FreeBSD PRs for