Hi there 👋

These days

I am working at Xibbon building fun mobile applications like Godot for iPad, La Terminal, El Pintador, some RealityKit/VisionOS libraries.

These days, when I am hacking for pleasure, I mostly do it in Swift:

• SwiftTerm - VT100/Xterm terminal emulator
• SwiftGodot - Swift bindings for the Godot game engine
• SwiftGodotKit - a companion to SwiftGodotKit to drive Godot from Swift.
• SkiaKit - Swift bindings to the Skia library
• TermKit - Text mode UI toolkit for Swift
• TextBufferKit - port of the Visual Studio Code TextBuffer storage engine to Swift
• PlaticaBot - my MacOS, iOS and WatchOS client for ChatGPT
• TurboSwift - my joke TUI IDE for Swift
• SwiftNavigation - RecastNavigation/Detour for Swift
• RealityActions - Cocos2D-inspired action framework for RealityKit.

Past

I have been involved in the open source world for many years, starting sometime around 1990-1991 or so.

Some of the project I started:

• The Midnight Commander File Manager for Unix

• Started the GNOME project, along Federico Mena.

• Created the Gnumeric spreadsheet

• Founded Ximian, which we sold to Novell in 2003, and we built:

  • Evolution an Email and Calendar app for Linux
  • Red Carpet software management suite
  • Mono: an open source implementation of .NET
    • I managed the team, and designed core pieces, and wrote most of the original C# compiler.
  • At Novell, we believed that Linux on the Desktop was the future, and we built both Gtk# (a Gtk+ binding to .NET) and many (by those days' standards) desktop applications for Linux (F-Spot, for photo management; Dashboard as an early live assistant; Beagle, for searching; Banshee, our desktop music player).
  • Started Moonlight, in a 21-day hack-a-thon which later would get funded by Microsoft and Novell.
  • Did everything in my power to get and keep Unity on the .NET ecosystem, and that is why we have C# in all those games now.

• Founded Xamarin, a company focused on bringing C# to mobile platforms, which we sold to Microsoft in 2016.

  • We built a .NET Runtime for Android and iOS, and built a cloud-based testing platform (Xamarin Test Cloud)
  • Xamarin Profiler
  • Xamarin Workbooks
  • Xamarin.Forms which has now morphed into .NET MAUI
  • SkiaSharp - Bindings to the Skia engine for C#
  • UrhoSharp - I loved SceneKit, but I wanted a cross platform solution, now Godot is getting closer to that.

I served on a few boards:

• Free Software Foundation
• Gnome Foundation
• Outercurve Foundation
• .NET Foundation

Participated in some international standards:

• ECMA Common Intermediate Language
• ECMA C#

Crashed a few parties and a few conferences.

At Novell, I was VP for the Developer Platform, and built Xamarin out of the ashes of Novell's hostile takeover.

At Microsoft, I was a Distinguished Engineer working on Xamarin and .NET, and later on Microsoft's Azure and AI efforts. I loved working with the .NET team and the C# language design team. I got a few things in the language that I am particularly proud of:

• Generic Math for .NET - originally part of the PartyDonk project
• Static Virtual Interface Members - for interop with iOS and Android
• Default Interface Methods - same inspiration, but also, because they are both righteous
• And many other quality of life tidbits

I left Microsoft in 2022.

Some of my C# repositories in GitHub:

• XtermSharp
• gui.cs: this project started as a two-day joke, and is now a popular UI toolkit for consoles.
• Mono - the VM and the class libraries are now just part of upstream .NET
• TensorFlowSharp - no longer maintained, there are better TensorFlow alternatives.
• TorchSharp - PyTorch bindings to .NET, now developed by the .NET foundation