SerenityOS: The second year

I remember first seeing links change color when hovered back in the IE3 days, and thinking it was the coolest thing ever.

Jesse ported Quake to Serenity. We didn't have sound at first but that was fixed later. Still, it was very exciting!

I decided to start building an IDE for C++ development. Since SerenityOS is a programmer's OS, a capable development environment is a must-have.

Getting a NES emulator running helped drive improvements for threading and timing APIs in the kernel. Check out the video to see me die before even reaching the 1st palace..

Someone put together a CTF (Capture The Flag) challenge at the 36c3 computer security conference. I learned about this when two exploits showed up (complete with write-ups!) on GitHub: one from Fire30 and another one from braindead.

This caught me by total surprise and I was a little bit disappointed at how easy it was to break into the system. This event sent me down a deep rabbit hole of learning about system security and applying everything I learned to secure Serenity. I wanted to make sure that the next CTF presented more of a challenge!

After the classic platformer VVVVVV was released as open-source, I wanted to get it running on Serenity. It was pretty easy to get it going since it used SDL and we already had a decent SDL port. The game was open sourced on Jan 10th and I had it running 2 days later.

Outside of enabling every protection mechanism the x86 has to offer, there was also a fair amount of architectural Unix-level security work. One of the most important pieces was adopting two OpenBSD-like system calls: pledge() and unveil().

I wrote about Serenity's pledge and unveil implementation on my blog.

The system's built-in time profiler became a lot more helpful when we added symbolication of kernel stack frames. You can tell them apart from userspace frames by the little red icon in the graph!

For my own birthday (February 9th), I celebrated by building a simple HTTP server for Serenity. I always loved the simple HTTP server that comes with Python, and I wanted something similar for Serenity.

People kept asking me if the web browser would ever support JavaScript. I honestly felt a bit intimidated when starting this project but I just did it anyway, and a whole bunch of people very quickly joined up to help out.

I started by implementing a simple AST interpreter, and building some test AST's by hand. Then Stephan added a parser, and Sergey made a REPL, and then things really took off, with Linus and Matt going especially deep.

To celebrate the project reaching 10'000 commits, I updated the main license file to assign copyright to "the SerenityOS developers" instead of just myself.

Browser development was moving forward with the LibJS engine allowing more and more complex things. But we were still limited to visiting unencrypted websites served over HTTP.

In comes LibTLS and LibCrypto! Thanks to some amazing work by Ali, assisted by Itamar and DexesTTP, we can now talk to HTTPS websites as well. The whole world opens up!

I was super excited when I could get Google loading for the first time!

Devashish implemented a JPEG decoder for LibGfx and suddenly we had access to a world of photos!

I spent a whole bunch of time improving standards compliance in the LibWeb engine's CSS implementation. I've been using the classic ACID2 test to drive some of the work. As you can see from the picture, a lot of work still remains!

One tool I've missed ever since starting the SerenityOS project is the amazing Valgrind.

I finally decided to do something about it, and I was curious how such a thing might be implemented, so I set out to create a workalike of my own.

I've hacked on x86 emulators in the past, so I decided to bring my knowledge in that area into Serenity and started building UserspaceEmulator (or UE for short), a program that implements a ring-3-only x86 CPU and intercepts system calls so we can instrument them.

Within a couple of weeks of hacking, I could run compiled programs without changing anything about them, and catch memory leaks just like Valgrind would!

I've always been a fan of desktop games, ever since the days of the Microsoft Entertainment Pack.

Here we were joined by two great games, a 2048 clone by Ali & Sergey, and a Chess game by Peter. The chess engine is still pleasantly stupid, so I can even beat it myself!

Also of note: the awesome icons in the system menu! Many of them were drawn by thankyouverycool (so thank you, thankyouverycool, very cool!)

Even more: the "About" box was redesigned by Nick, and Buggie the system mascot was drawn by Simon! These things happened much earlier but I'm mentioning them here since they are visible in the screenshot.

Itamar started adding support for Git integration (diffing, staging, commits) to the HackStudio IDE.

Note that this is an optional feature that is only available if you have the git port installed. HackStudio is the only program in the system that makes use of ports since we don't have our own implementations of git, a compiler, or a linker... yet. :^)

The Spreadsheet app was started by Ali and is powered internally by the LibJS JavaScript engine. Cell expressions are evaluated as JS. It feels really neat so far, although we're still figuring out how it should work.

It even has built-in documentation, which is generated from the JavaScript source code!

While we've had a system clipboard for a long time, it only recently became possible to copy anything other than text between apps.

Here I had just added an image context menu in the Browser so you can copy images from the web directly to the clipboard!

Also on display: the PixelPaint app (formerly PaintBrush), which became a layer-based image editor in the last year.

I had to fix some CSS bugs in the LibWeb engine while putting together this page. I have also discovered a whole bunch of things that need fixing. But this is where we are right now!

Happy 2nd birthday SerenityOS! I'm so proud of you, and of all the people who have worked on you!