Why we built a desktop app on local Flask + browser UI instead of PyQt or Electron

When you double-click WP Maintenance Manager, it opens a browser tab — and the entire UI lives inside that tab. No native window is created. It's an unusual structure for a first-time user, and the natural question is: "why a browser?" That choice was an intentional design decision when building a Python desktop application. Here's the comparison that led to it, and the side effects of the choice. Four realistic options For a WordPress maintenance automation tool, four implementation styles were practical: Approach UI Distribution size Dev cost Per-OS extra work Native (Swift / WPF) OS-native windows Small–medium High (separate impl per OS) Heavy PyQt / PySide Qt widgets Medium (~80 MB) Medium Light Electron Chromium-embedded web UI Large (~150 MB+) Medium Light Local Flask + system browser System browser tab Small (~50 MB) Medium Light PyQt was a serious early candidate. A Python-only stack is appealing, but widget styling drifts subtly between OSes, Qt's layout system demands constant attention, and resolving Qt plugins under PyInstaller is fiddly. Dev velocity was not where it needed to be. Electron is the industry-standard choice for cross-platform UI, with the big benefit that HTML/CSS-based UIs are quick to write. But the distribution is well over 100 MB, and memory consumption is heavy. For a tool that often runs in the background, that overhead is too much to justify. Why local Flask + browser won The final structure was Flask (Python's lightweight web framework) + the system browser for UI. The decision rested on three axes: 1. The backend had to be Python anyway SSH connections via fabric / paramiko , browser automation via playwright , encryption via cryptography — every library at the core of WordPress maintenance lives in the Python ecosystem. Writing the backend in another language wasn't really an option. If Python is already required on the backend, putting the UI in Python too keeps distribution simple. 2. HTML/CSS/JS makes UI iteration fast Flask r