Karl Traunmüller
@compositorapp.bsky.social
Mac & iOS developer. Author of Compositor, the WYSIWYG LaTeX Editor for Mac and Windows.
https://compositorapp.com/
https://github.com/ktraunmueller
https://compositorapp.com/
https://github.com/ktraunmueller
Pinned
This is a continuation of the now abandoned @compositorapp Twitter/X account. News & updates about the Compositor app for Mac & Windows will be posted here, and also on my @compositorapp Mastodon account.
If anyone is interested in what’s happening with Swift on Windows, Saleem (@compnerd) is hosting biweekly Windows office hours. See this Swift Forums post: forums.swift.org/t/introducin...
I’ve taken something away from almost every meeting.
I’ve taken something away from almost every meeting.
Introducing Windows Office Hours!
Hello Windows Developers! There has been a significant amount of interest in Windows Swift development for both developing applications as well as interest from potential contributors to the toolch...
forums.swift.org
January 23, 2026 at 1:20 PM
If anyone is interested in what’s happening with Swift on Windows, Saleem (@compnerd) is hosting biweekly Windows office hours. See this Swift Forums post: forums.swift.org/t/introducin...
I’ve taken something away from almost every meeting.
I’ve taken something away from almost every meeting.
The new source code editor is finally integrated into the Windows app. Looks and behaves pretty much identical to the Mac app. This brings us close to the next prototype release, milestone 0.5 #WYSIWYG #LaTeX github.com/ktraunmuelle...
January 23, 2026 at 9:23 AM
The new source code editor is finally integrated into the Windows app. Looks and behaves pretty much identical to the Mac app. This brings us close to the next prototype release, milestone 0.5 #WYSIWYG #LaTeX github.com/ktraunmuelle...
Taking a close look at how the new ASCII piece table responds to different editing scenarios (WYSIWYG editing, in this case).
January 9, 2026 at 2:24 PM
Taking a close look at how the new ASCII piece table responds to different editing scenarios (WYSIWYG editing, in this case).
I am generally not a fan of UI tests, but I have some "smoke test" UI tests. I am not using XCUITest here, however -- this is XCTest with the app itself as the test host, an approach I described in this blog post: compositorapp.com/blog/2018-09...
January 9, 2026 at 11:52 AM
I am generally not a fan of UI tests, but I have some "smoke test" UI tests. I am not using XCUITest here, however -- this is XCTest with the app itself as the test host, an approach I described in this blog post: compositorapp.com/blog/2018-09...
At the heart of Compositor's LaTeX source code handling sits an ASCIIString type. As part of the new source editor foundation, I have replaced its backing store with an ASCIIPieceTable type. The heart surgery is now complete, and my extensive test suite gives me confidence about the changes.
January 8, 2026 at 11:18 AM
At the heart of Compositor's LaTeX source code handling sits an ASCIIString type. As part of the new source editor foundation, I have replaced its backing store with an ASCIIPieceTable type. The heart surgery is now complete, and my extensive test suite gives me confidence about the changes.
All of the editor layout, navigation, and selection logic is now in the shared Core library that's used by both the Mac and Windows apps. On Mac, the NSView just forwards input events and contains a few lines of drawing code.
December 29, 2025 at 11:22 AM
All of the editor layout, navigation, and selection logic is now in the shared Core library that's used by both the Mac and Windows apps. On Mac, the NSView just forwards input events and contains a few lines of drawing code.
Basic mouse and keyboard navigation, together with selection, in the new source code editor (here, on the Mac - Windows will follow soon).
December 28, 2025 at 12:38 PM
Basic mouse and keyboard navigation, together with selection, in the new source code editor (here, on the Mac - Windows will follow soon).
When developing UI components, I like to employ snapshot tests for fast turnaround during prototyping. No need to compile and launch an entire host app and manually run through a scenario - just run the test and check the image output.
December 20, 2025 at 11:49 AM
When developing UI components, I like to employ snapshot tests for fast turnaround during prototyping. No need to compile and launch an entire host app and manually run through a scenario - just run the test and check the image output.
And here's the new source code editor making its first appearance! (in the Mac app) Rendering performance is looking excellent, thanks to using the same basic approach to text rendering as in the DVI views (which has proven to be very fast).
December 19, 2025 at 12:08 PM
And here's the new source code editor making its first appearance! (in the Mac app) Rendering performance is looking excellent, thanks to using the same basic approach to text rendering as in the DVI views (which has proven to be very fast).
A little peek into my style of working on problems like the source code editor line buffer management. I usually work bottom-up, covering all important code with unit or snapshot tests as I go.
December 18, 2025 at 11:30 AM
A little peek into my style of working on problems like the source code editor line buffer management. I usually work bottom-up, covering all important code with unit or snapshot tests as I go.
The first rendered output of what will become the cross-platform LaTeX source code editor in Compositor. Quite a bit of work has gone into text storage data structures and glyph run handling before this. github.com/ktraunmuelle...
December 15, 2025 at 11:39 AM
The first rendered output of what will become the cross-platform LaTeX source code editor in Compositor. Quite a bit of work has gone into text storage data structures and glyph run handling before this. github.com/ktraunmuelle...
Compositor for Windows 0.4.1 is available 📦 This bugfix release fixes two crashes. compositorapp.com/blog/2025-11...
Compositor for Windows 0.4.1
Compositor for Windows release 0.4.1 is available! 🎉
compositorapp.com
November 23, 2025 at 10:48 AM
Compositor for Windows 0.4.1 is available 📦 This bugfix release fixes two crashes. compositorapp.com/blog/2025-11...
There will be a Windows 0.4.1 release (and possibly a 0.4.2 release as well) to fix the two currently known crashers on Windows. I want to see those fixed before moving on to new features. github.com/ktraunmuelle...
ktraunmueller/Compositor
The WYSIWYG LaTeX Editor for macOS and Windows. Contribute to ktraunmueller/Compositor development by creating an account on GitHub.
github.com
November 17, 2025 at 6:38 PM
There will be a Windows 0.4.1 release (and possibly a 0.4.2 release as well) to fix the two currently known crashers on Windows. I want to see those fixed before moving on to new features. github.com/ktraunmuelle...
The Compositor for Windows release 0.4 is now available! 🎉 Read all about it on the blog: compositorapp.com/blog/2025-11... #TeXLaTeX
November 15, 2025 at 2:48 PM
The Compositor for Windows release 0.4 is now available! 🎉 Read all about it on the blog: compositorapp.com/blog/2025-11... #TeXLaTeX
During installer testing, a problem with the FileOpenPicker came up, which I need to fix before the Compositor for Windows 0.4 release. Shouldn't take long to sort out, I hope.
November 14, 2025 at 4:19 PM
During installer testing, a problem with the FileOpenPicker came up, which I need to fix before the Compositor for Windows 0.4 release. Shouldn't take long to sort out, I hope.
The Compositor for Windows 0.4 milestone is a wrap, expect a release announcement in the next few days! 🎉 github.com/ktraunmuelle...
November 10, 2025 at 7:43 PM
The Compositor for Windows 0.4 milestone is a wrap, expect a release announcement in the next few days! 🎉 github.com/ktraunmuelle...
The new compositorapp.com website is live! 🎉 I felt compelled to update the website a little earlier than planned, because it appears I am already the target of Chinese scammers 🤡 I have thus included a corresponding warning on the new website. compositorapp.com #LaTeX
November 5, 2025 at 8:15 PM
The new compositorapp.com website is live! 🎉 I felt compelled to update the website a little earlier than planned, because it appears I am already the target of Chinese scammers 🤡 I have thus included a corresponding warning on the new website. compositorapp.com #LaTeX
Sneak peek: The Compositor product website will get a (long overdue) refresh soon! 🎉
October 29, 2025 at 6:35 PM
Sneak peek: The Compositor product website will get a (long overdue) refresh soon! 🎉
The next milestone of Compositor for Windows is well underway! I have just cleared one hurdle that was causing the long delays after each keystroke, and I can now focus on the automatic package downloader and installer and #WYSIWYG editing of arbitrary #LaTeX documents. github.com/ktraunmuelle...
ktraunmueller/Compositor
The WYSIWYG LaTeX for Mac (and soon, Windows). Contribute to ktraunmueller/Compositor development by creating an account on GitHub.
github.com
October 23, 2025 at 10:00 AM
The next milestone of Compositor for Windows is well underway! I have just cleared one hurdle that was causing the long delays after each keystroke, and I can now focus on the automatic package downloader and installer and #WYSIWYG editing of arbitrary #LaTeX documents. github.com/ktraunmuelle...
A new public prototype of a Windows version of my previously Mac-only WYSIWYG LaTeX app Compositor is now available! Find out more on the blog: compositorapp.com/blog/2025-09... #TeXLaTeX #SwiftOnWindows
September 24, 2025 at 3:45 PM
A new public prototype of a Windows version of my previously Mac-only WYSIWYG LaTeX app Compositor is now available! Find out more on the blog: compositorapp.com/blog/2025-09... #TeXLaTeX #SwiftOnWindows
The Compositor for Windows 0.3 milestone is ready to go! 🎉 I will publish a blog post with details and installer links in the next few days. #SwiftOnWindows
September 22, 2025 at 7:27 PM
The Compositor for Windows 0.3 milestone is ready to go! 🎉 I will publish a blog post with details and installer links in the next few days. #SwiftOnWindows
If executables from debug builds of your mixed Swift/C++ project run really slow, check if you're specifying -O0 in the Swift Package manifest or CMake configuration. That makes std::map extremely slow. Use -Og instead.
September 17, 2025 at 9:31 PM
If executables from debug builds of your mixed Swift/C++ project run really slow, check if you're specifying -O0 in the Swift Package manifest or CMake configuration. That makes std::map extremely slow. Use -Og instead.
With some help from @compnerd.bsky.social on the Swift forums, I now have a working Swift Testing setup integrated with CMake / VSCode / LLDB for unit-testing the Windows-specific parts of the Compositor app. github.com/ktraunmuelle... #Swift #SwiftOnWindows
July 2, 2025 at 3:47 PM
With some help from @compnerd.bsky.social on the Swift forums, I now have a working Swift Testing setup integrated with CMake / VSCode / LLDB for unit-testing the Windows-specific parts of the Compositor app. github.com/ktraunmuelle... #Swift #SwiftOnWindows
I really love how well a CMake-based build setup for a Swift project works on Windows. For integration with VSCode, I've configured the default build task (Ctrl+Shift+B) to "cmake --build --preset debug", and it picks up any changes in the whole project tree. It even feels better than Xcode & SPM.
June 19, 2025 at 5:45 PM
I really love how well a CMake-based build setup for a Swift project works on Windows. For integration with VSCode, I've configured the default build task (Ctrl+Shift+B) to "cmake --build --preset debug", and it picks up any changes in the whole project tree. It even feels better than Xcode & SPM.
Just finished migrating the build for Compositor on Windows from Swift Package Manager to CMake (with some help from ChatGPT), consolidating the WinRT repos into a monorepo along the way. CMake is actually great! #Swift #SwiftOnWindows #CMake github.com/ktraunmuelle...
Windows 0.3 Milestone · ktraunmueller/Compositor
The WYSIWYG LaTeX for Mac (and soon, Windows). Contribute to ktraunmueller/Compositor development by creating an account on GitHub.
github.com
May 27, 2025 at 7:53 PM
Just finished migrating the build for Compositor on Windows from Swift Package Manager to CMake (with some help from ChatGPT), consolidating the WinRT repos into a monorepo along the way. CMake is actually great! #Swift #SwiftOnWindows #CMake github.com/ktraunmuelle...