These are the projects on which most of my time is currently spent.

Pushover (2012 - present) (Ruby, Ruby on Rails, MariaDB, Objective C, Java, Javascript)

Pushover is a platform and bundled client applications for sending and receiving push notification messages on Android, iOS, and Desktop devices. It has a simple REST API that allows quick integration with servers, websites, backend processes, e-mail servers, and anything else needing to send notifications, without having to write any frontend applications for receiving them. It currently processes over three million messages a day.

In addition to the backend API, message daemons, and e-mail gateway, I authored and maintain the device clients for Android, iOS, and web browsers, which were written in native Java, Objective C, and Javascript, respectively.

I do all of the day-to-day operations from customer support and billing, to system administration, to software development on the device clients, backend API, and frontend website.

OpenBSD (2001 - present) (C)

I have been an OpenBSD developer (jcs@) since 2001. I initially focused on ports and packages that pertained to the use of OpenBSD at my day job, then slowly moved into writing userland and then kernel code.

In 2004, I wrote the nvram(4) driver for i386 providing /dev/nvram (just to support running tpb on various ThinkPad laptops).

In 2005, I wrote tftp-proxy(8) for pf while working at my old job, to support our new OpenBSD-based PBX and firewall products which had many VoIP phones requiring TFTP for provisioning. tftp-proxy was later rewritten by another developer to be a standalone daemon instead of relying on inetd to increase performance.

In 2008, I wrote the acpithinkpad(4) ACPI driver to support hardware buttons and various quirks on newer ThinkPads, largely deprecating nvram(4) and the tpb package.

In 2013, I wrote the ubcmtp(4) USB driver to support Broadcom multi-touch trackpads found on MacBook laptops.

In 2016, I wrote a number of new hardware drivers:

  • dwiic(4) driver for the Synopsys DesignWare I2C controller
  • ihidev(4) driver for HID-over-I2C devices
  • hidmt(4) HID driver for Windows Precision Touchpad devices
  • ims(4) and imt(4) HID-over-I2C drivers to support multitouch touchpads
  • acpials(4) driver for ambient light sensors found on some laptops
  • acpicbkbd(4) driver for keyboard backlight on the Chromebook Pixel and HP Chromebook 13
  • iatp(4) driver for the Atmel touchpad and touchscreen on the Chromebook Pixel
  • chromeec(4) driver for the Chrome Embedded Controller found on the Chromebook Pixel, among others (never committed upstream)

In 2017, I wrote the acpisbs(4) driver for ACPI Smart Batteries.

In 2018, I wrote the umt(4) driver for USB Windows Precision Touchpad devices like on the Microsoft Surface Go.

In 2020, I wrote the umstc(4) driver for USB Microsoft Surface Type Cover keyboards, and the acpihid(4) driver for ACPI HID event and 5-button array devices, both used on the Microsoft Surface Go.

Other Active Projects

Most of my open source code can be found on GitHub.

ChiBUG (2016 - current)

I founded the Chicago-Area BSD Users Group to facilitate discussion and support for users of the various BSD projects in the Chicago area.

Countinual (2013 - present) (Ruby on Rails, Ruby, MariaDB)

Countinual is a self-contained, lossless statistics and graphing system, similar to Graphite. I initially wrote it to store and graph simple counters, such as the number of Pushover signups per day. It now tracks all kinds of app metrics, server statistics, and bandwidth for all of my servers. (2011 - present) (Ruby on Rails, MariaDB) is an integrated reader for things like RSS feeds and Twitter feeds. It was in varying states of development over the years and was set to launch at some point, until Twitter changed the terms of use for its API and overall usage of RSS on the web declined greatly.

It started life as a Ruby on Rails application, was then rewritten in my halfmoon PHP framework, then later rewritten again in Ruby on Rails.

I still use it every day as my own RSS reader and Twitter client. (2021-present) (Ruby)

I created this desktop screenshot-sharing website to make it easier to describe all of the programs running in a screenshot when sharing it, and to provide a library of screenshots of any given program, window manager, or operating system.

Kludge BBS (2015-present) (Ruby, Telephony)

I created this multiuser BBS software for the temporary Lobsters BBS but later setup my own system while continuing to improve the software. It currently offers telnet, SSH, dialup modem, and web (Javascript+WebSockets) interfaces to a central backend which supports threaded message forums, DOVE-net forum feeds, multiuser chat, and file storage areas. Although it doesn’t see much traffic, I have tended to it over time to add new features and improve compatibility with particular client devices, such as VT52 support.

Macintosh 512Ke (2017-present) (Hardware restoration and C development)

I never owned Apple hardware when I was young, but I wanted a vintage Mac on my desk to play around with and restore. I initially added a Floppy Emu as an HD20 hard drive and a WiFi232 in an Apple Modem for telnetting to BBSes. I later upgraded it with a “Mac Rescue” board which adds 4Mb of RAM and SCSI support, basically bringing it up to Mac Plus specifications, and replaced the Floppy Emu with a SCSI2SD drive.

Payphone (2013-present) (Asterisk, Telephony)

A fun project to get a working payphone in my home, complete with coin detection and totalizing. (2020 - current) (Ruby)

A simple .plan hosting site, available via web and finger.

progman (2020 - current) (C)

A window manager modeled after Windows 3.1’s Program Manager.

ReStuff (2020 - current) (Ruby, Virtualization)

ReStuff is “StuffIt as a Service”, used to convert StuffIt 5 archives into the older StuffIt 3 format which can be opened on System 6 Macs.

sdorfehs (Pronounced “starfish”) (2019 - current) (C)

My fork of the Ratpoison tiling window manager which I forked after maintaining my own branch of patches for many years.

Series: C Programming on System 6 (2020 - present) (C)

I started writing an IMAP client for Mac System 6, doing all development in THINK C on my Mac 512Ke. A few months into it, I started recording videos of my development to help others get started in C development on System 6.

Twitframe (2013 - present)

In the spirit of Colin Percival’s Payment iframe, Twitframe allows one to display Embedded Tweets on one’s website to dynamically show retweet and favorite counts, inline media/card data, and allow users to retweet/reply /favorite Tweets, all while isolating the Javascript and DOM manipulation to an embedded iframe.

WiFiStation (2021-present) (Z80 Assembly, PCB Design)

I developed a hardware WiFi adapter for the Cidco MailStation, and am currently selling them as a kit.

xbanish (2013-present) (C)

xbanish is a small X11 utility to automatically hide the mouse cursor when typing, and show it again when the mouse is moved.

Completed/Abandoned Projects

Adium PipeEvent Plugin (2010-2012) (Objective C)

PipeEvent was a plugin for Adium that could be used to pipe event information to an external script. It stopped working with newer versions of Adium and I’ve since developed and now use a Pushover-specific plugin.

Blandroid ( (2011 - 2012) (Java, C, PHP)

Blandroid was an Android (2.3 to 4.1) ROM focusing on stability, supporting the AOSP devices Nexus One, Nexus S, Nexus S 4G, and the Galaxy Nexus. It had a small following of users that didn’t want to put up with the instability of Cyanogenmod and other Android ROMs. I added some minor features to the ROM that were later made obsolete by Android 4.

I discontinued the project as Android 4 became more popular and Google’s separation between AOSP and Android proper became wider. I now just use factory images on my Android test devices.

Corduroy ( (2006 - 2012) (Ruby/Ruby on Rails, MySQL, OFX, Plaid)

Corduroy was a web-based billing system for small businesses. I created it in 2006 to handle the invoicing for my company after I got fed up using QuickBooks. After adding things like banking integration for downloading transactions (via OFX), online invoice payment through PayPal and other merchants, and project management, I turned it into a software-as-a-service and began hosting it for other companies. The service was not a major focus of my company and was not advertised much, so it didn’t gain many users.

Many competitors had been established that were much more popular and better suited for this type of service, so I stopped offering it in 2012. I still use it for my company’s book keeping and occasionally add features, such as switching from OFX to using Plaid’s API for increased security and easier maintenance.

Domain iCal (domainical.{org,com}) (2011 - 2018) (PHP/Halfmoon, MySQL)

A free site that let one list domain names which would be looked up through whois and/or queried through SSL and their domain and SSL certificate expiration dates were published as an iCalendar feed for easy monitoring.

I later purchased the .com domain to try to commercialize the service but the constant changes among the whois servers for all available TLDs (which was constantly expanding) was too difficult to keep up with, so I just discontinued the service.

Endless (2014-2019) (Objective C)

Endless was a web browser for iOS with enhanced security and privacy, like HTTPS Everywhere and analytics blocking built in.

It become the basis for the Tor Project’s Onion Browser rewrite.

I stopped development when Apple deprecated UIWebView and announced that applications were going to be prevented from using it.

Fitbit Low Battery Notifier ( (2011 - 2016) (Ruby on Rails, MySQL, Pushover, Twilio)

This free service was built to use the Fitbit API to monitor the battery level of each user’s Fitbit tracker and notify them by e-mail, SMS, and/or Pushover when the battery is low or the tracker had not synched within a certain timeframe.

It was used by over 73,000 Fitbit users and sent out more than 2 million alerts in the 5 years it was in operation.

It was shut down in mid-2016 due to the high costs associated with sending out SMS messages every day and its declining usefulness since Fitbit eventually added e-mail and push notifications to its mobile apps to alert of low battery status.

Garbage Podcast (2015 - 2019)

Originally hosted at, this was a technology-focused podcast that was produced with fellow OpenBSD developer Brandon Mercer where we complained about technology and occasionally provided useful information. Episodes were recorded weekly on Thursday evenings and released on Fridays for about ten months straight before we got too busy to continue the pace, finally ending in early 2019.

I did the show’s audio editing and backend administration, such as developing the custom CMS and hosting the website. (2008 - 2012) (PHP/Halfmoon, SQLite)

This single-page website was created in May of 2008 as an alternative to busy, ad-ridden sites like All I cared about was whether it was going to rain that day, so I created this simple site to automatically lookup your city/state by geolocating your IP address, check the weather for that city, then parse the result and tell you in a one-word answer “yes” or “no”, whether it was going to rain.

When it was initially released, it made the front page of Hacker News, Delicious, and Mashable.

In July 2009, some Chinese developers released a cheap-looking iPhone app that cost 99 cents and would just load and show the answer. I blocked the app from accessing the site and it has since been removed from the App Store.

In March 2011, an API was created for integration into the DuckDuckGo search engine’s zero-click information for “is it going to rain” and related searches.

In August 2012, Google shut down its weather API without notice and since the only remaining weather APIs cost money, the site was forced to shut down.

halfmoon (2010 - 2012) (PHP)

halfmoon is a small MVC framework for PHP that does things like Ruby on Rails (2.3) wherever possible. I started writing it in 2010 after doing Rails for a number of years and needing to use PHP for a small web project. I’ve since used it for a handful of small web projects and APIs, but I have mostly switched back to using Rails.

HN Trades ( (2010 - 2012) (PHP/Halfmoon, MySQL)

HN Trades was a site for Hacker News users to trade domain names, books, and other stuff. It was created after seeing yet-another thread on HN about unused domain names.

Lobsters (2012 - 2017) (Ruby on Rails, MySQL)

A link aggregation site that I created in 2012 after being banned from Hacker News. The backend of the site was open source.

After running the site for five years, I handed it over to the community and it continues to grow.

Metra Train Schedules ( (2009 - 2012) (Ruby on Rails, MySQL)

Metra spent part of $3.9M on a new website in 2009 that still had no mobile browser support. I created this website, optimized for the iPhone and Android, to display train schedule and delay information. Metra later added a basic mobile interface to their site, though its interface was still quite clumsy.

The maintenance required to manually update the schedules from Metra’s PDFs, as well as the availability of many offline iPhone and Android applications and the Google Transit mobile site prompted this site to be shut down in early 2012. (2000 - 2009) was a personal server that I colocated at the ISP I used to work at and eventually turned into a second-level OpenBSD FTP, Web, AnonCVS, and CVSup mirror (and occasional Tor exit node). After a number of hardware failures and upgrades, I finally took it out of service in 2009 and sold the domain name due to its high renewal cost being a “premium .fm domain”.

Rubywarden (2017 - 2020) (Ruby, Sinatra)

A small, self-contained alternative API backend to the open source Bitwarden password management applications.

I documented the API and wrote the server to facilitate migrating from 1Password.

I stopped development in 2020 when it became too difficult to keep up with upstream client changes, and there is now another open source implementation of Bitwarden’s API.