I started working on Edna several months ago and I’ve implemented lots of functionality. Edna is a note taking application with super powers. I figured I’ll make a series of posts about all the features I’ve added in last few months. The first is multiple notes. By default we start with 3 notes: scratch inbox daily journal Here’s a note switcher (Ctrl + K): From note switcher you can: quickly find a note by partial name open selected note with Enter or mouse click create new note: enter fully unique note name and Enter or Ctrl + Enter if it partially matches existing note. I learned this trick from Notational Velocity delete note with Ctrl + Delete archive notes with icon on the right star / un-star (add to favorites, remove from favorites) by clicking star icon on the left assign quick access shortcut Alt + <n> You can also rename notes: context menu (right click mouse) and This note / Rename Rename current note in command palette (Ctrl + Shift + K) Use context menu This note sub-menu for note-related commands. Note: I use Windows keyboard bindings. For Mac equivalent, visit https://edna.arslexis.io/help#keyboard-shortcuts

Less known desktop UI frameworks Writing desktop software is hard. The UI technologies of Windows or MacOS are awful compared to web technology. What can trivially be done with HTML/CSS/JavaScript in few minutes can take hours using Windows’s win32 APIs or Mac’s Cocoa. That’s why the default technology for desktop apps, especially cross-platform, is Electron: a Chrome browser combined with Node runtime. The problem is that it’s bloaty: each app is a unique build of Chrome with a little bit of application code. Chrome is over 100MB so many apps ship less than 1MB of code in a 100M wrapper. People tried to address the problem of poor OS APIs by writing UI frameworks, often meant to be cross-platform. You’ve heard about QT, GTK, wxWindows. The problem with those is that they are also old, their APIs are not the greatest either and they are bloaty as well. There just doesn’t seem to be a good option. Writing your own framework seems impossible due to the size of task. But is it? I’ll show a couple of less-known UI frameworks written mostly be a single person, often done simply to enable writing an application. SWELL in WDL WDL is interesting. Justin Frankel, the guy who created Winamp, has a repository of C++ code he uses in different projects. After selling Winamp to AOL, a side quest of writing file sharing application, getting fired from AOL for writing file sharing application, he started a company building Reaper a digital audio workstation software for Windows. Winamp is a win32 API program and so is Reaper. At some point Justin decided to make a Mac version but by then he had a lot of code heavily using win32 APIs. So he did what anyone in his position would: he implemented win32 APIs for Mac OS and Linux and called it SWELL - Simple Windows Emulation Layer. Ok, actually no-one else would do it. It was an insane idea but it worked. It’s important to not over-state SWELL capabilities. It’s not Wine. You can’t take any win32 program and recompile for Mac with SWELL. Frankel is insanely pragmatic and so is his code. SWELL only implements the subset of APIs he uses in Reaper. At the same time Reaper is a big app so if SWELL works for Reaper, it could work for your app. WDL is open-source using permissive MIT license. Sublime Text For a few years Sublime Text was THE programmer’s editor. It was written by a single developer in C++ and he wrote a custom UI toolkit for it. Not open source but its existence shows it can be done. RAD Debugger RAD Debugger is an open-source Windows debugger for C/C++ apps written in C by mostly a single person. It implements a custom UI framework based on 3D renderer. The UI is integral part of the the app but the code is well structured so you probably can take just their UI / render code and use it in your own C / C++ app. Currently the app / UI is only for Windows but it’s designed to be cross-platform and they are working on porting the renderer to Mac OS / Linux. They use permissive MIT license and everything is written in C. Dear ImGUI Dear ImGui is a newer cross-platform, UI framework in C++. Open source, permissive MIT license. Written by mostly a single person. Ghostty Ghostty is a cross-platform terminal emulator and UI. It’s written in Zig by mostly a single person and uses it’s own low-level GPU renderer for the UI. You too can write your own UI framework At first the idea of writing your own UI framework seems impossibly daunting. What I’m hoping to show is that if you’re ambitious enough it’s possible to build cross platform desktop apps that are not just bloated 100MB Chrome wrappers around few kilobytes of custom code. I’m not saying it’s a simple thing, just that enough people did it that it’s possible. It shouldn’t be necessary but both Microsoft and Apple have tragically dropped the ball on providing decent, high-performance UI libraries for their OS. Microsoft even writes their own apps, like Teams, in web technologies. Thanks to open source you’re not at the staring line. You can just use Dear ImGUI or WDL’s SWELL. Or you can extract the UI code from RAD Debugger or Ghostty (if you write in Zig). Or you can look at how their implementation to speed up your own design and implementation.

This is a real life example of tweaking UI in Edna, my note taking application with super powers. Ask AI is a simple AI chat: you write a question, send it to LLM model and get a response. Here’s my first version of the UI: What is good and bad about this version? Good: there’s a learn more link. This is not an obvious feature because you need to pick a model and provide an API key. An easy access to an explanation is good. Bad: It’s not clear enough that you need to provide an API key. To make things even more confusing, for models from OpenAI or xAI you can use either OpenAI/xAI key or OpenRouter key. Hence the Use OpenRouter checkbox. I decided to make things more explicit: I think it’s clearer, especially for someone new to the API keys. Checkbox is gone. Now I just ask for one or the other and will use whichever is given. A learn more links to section of the docs explaining how to get API key and answering basic questions someone new might have. Visually I think it would look better if the link was on the right but then it would be easier to miss. Functionality over aesthetics. Another subtle touch: explicit placeholder Enter OpenAI API key text in input field.

Here’s what I learned about calling LLM APIs from the browser when building AI chat functionality in my note taking app Edna. The API I care about is getting LLM response to a question in a streaming way. OpenAI pioneered this and created https://api.openai.com/v1/chat/completions POST API. Others created a compatible API for their LLM to make it easy for programmers to migrate. xAI has https://api.x.ai/v1/chat/completions for Grok and OpenRouter has https://openrouter.ai/api/v1/chat/completions. Google and Anthropic have similar APIs but they use CORS to disallow calling them from the browser. Baffling restriction. For now I decided to not support them directly. I could route the requests via the server but I can use OpenRouter instead. I’ve seen TypingMind call Google API from the browser but using a different API endpoint. Again, for now I decided to not support Google directly. OpenRouter is an interesting service and business. They provide unified API for lots of different models so I can use Google or Anthropic APIs via OpenRouter and lots of other models. They charge 5% on top of what they pay the providers, which is reasonable if you consider that they probably pay ~3% for processing credit card fees. For now I support OpenAI and Grok directly and everyone else via OpenRouter.