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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. I maintained games/nethack, databases/rrdtool12, sysutils/bsdhwmon, and sysutils/mcelog; maybe others too, I've since forgotten.
  • Author of bsdhwmon, an open source SMBus-focused hardware monitoring utility for FreeBSD.

Tomato firmware

  • Have used Tomato since the RTM of the Linksys WRT54G v1.1. I even wrote a serial port mod for it.
    • I've run Tomato on the Asus RT-N16 (MIPS), Asus RT-N66U (MIPS) (what I use now), and a Netgear R7000 (ARM) (which I didn't like -- too large, ran hot, felt shoddy).
  • Contributor on the forum Tomato firmware sub-board where I do a little bit of everything, but most of my time is spent providing support/help for free.
  • As of 2017/03/10, I no longer participate in the project. I grew tired of repeating myself, tired of users with no technical skill set demanding features, tired of repeating myself with regards to technical aspects (of everything, not just Tomato!). Most of the Tomato code base is a complete and total unmanageable mess (i.e. it is overwhelming to try and fix; time would be better spent starting from scratch). These and several other reasons are why I left the project (as a community member and committer/code contributor).

Apple IIGS

I was the co-founder of the Apple IIGS demo and CDA (Classic Desk Accessory) utility group called Digital Exodus back in the early 90s. We released the following software, all written in pure 65816 assembly:

  • DOCVu (CDA) — a graphical user interface for viewing the real-time inner workings of the Ensoniq ES5503 DOC audio chip
  • QuickPort II (CDA) — a small CDA that allowed setting the IIGS serial port to speeds above 19200bps
  • Xmas Demo — a classic 3.5" disk demo showing off some capabilities of the IIGS, as well as the tale of our road trip from Oregon to California to attend Apple Expo West in 1993

I also used to post on comp.sys.apple2 from roughly 1992 to 1995, and later on comp.emulators.misc. More often than not, I made a complete ass out of myself -- that's youth for you.


  • 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 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.
  • Was heavily involved in EFnet IRC channels #snesdev, #AppleIIGS, #emu, #nesdev, and #romhack.


  • 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.
  • There's an old thread about why I stopped doing nesdev for almost a decade.[4]
    • As of mid-2017, I no longer involve myself with the nesdev forum or general nesdev community. I also no longer moderate the forum or the wiki.
  • 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. It's kinda weird seeing your name in published print, but it's also a good feeling.


  • 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 (I classify myself as "politically independent"), and 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.
  • In late February 2017, I underwent a cholecystectomy (removal of gallbladder) due to discovery of several large gallstones (my surgeon described my gallbladder, once removed, as "chocked full" and was likely to burst within a year or two). As of mid-March 2017, I am still recovering (recovery has been slow). The surgery has had an overall effect on my IBS (in both good and bad ways), and I am learning to cope with these changes.

Old contact details

I've had so many different aliases/pseudo-names, Email addresses, and personal home page locations throughout my life that it's almost staggering; "Googling" for myself brings back lots of memories, and lots of confusion as well. I wanted to make a list of them, so that people from yesteryear had a way to find me. Some of these were redirectors (forwarders) to other places.

Monikers (aliases/pseudo-names)

  • Sonic (late 80s/early 90s, local BBSes)
  • Gargoyle (late 80s/early 90s, local BBSes)
  • Ryu (early 90s, local BBSes)
  • Shadow (early-to-mid 90s, I forget the exact context)
  • Yoshi (early-to-mid 90s)
  • Y0SHi (mid-to-late 90s)
    • I switched from Yoshi to Y0SHi (with a zero) because of some hacker/cracker asshole on EFnet (IRC) who kept insisting Yoshi was his nickname. I simply gave in, because it wasn't worth fighting over nor the risk of being associated with that sort of trash
  • k9 (late 90s/early 2000s; people from my days of administrating will probably remember me as this)
  • dukandricka
  • tsuchinoko
  • fuhennori
  • koitsu

Email addresses

  • chadwij@{nyssa,jacobs} (early 90s)
  • yoshi@{atlantis,kira} (early 90s)
  • (early 90s)
  • (early 90s)
  • (1994)
  • (1995-1997)
  • (1997)
  • (1997-1998)
  • (1997-1998; yes, I was friends with Kaitlin/Steven for several years until she was killed in 2005)
  • (1997-2006)
  • (2006-2012)

Home pages



  1. Why I left the FreeBSD Project:
  2. FreeBSD PRs for
  3. FreeBSD PRs for
  4. nesdev forum post: