Building WSA Installer: Python, Rust & Flet

The Stack

WSA Installer is a Windows desktop app built around a Python core with a Flet (Flutter) GUI, protected by native Rust modules, and packaged with NSIS. The result is a ~228 MB setup that runs completely offline after install.

Flet GUI (app.py)

Around 11,000 lines of Python drive the 5-step frameless wizard, real-time progress UI, glassmorphism design, and all sub-dialogs (repair, update, uninstall, file sharing). Flet lets the same code render a native-feeling window without writing Flutter by hand.

InstallerLogic Engine

The engine handles parallel chunked downloads with resume, 7z extraction via tar.exe, WSA package verification (filelist.txt), registry patching, and ADB automation for Play Store. It's the 'brain' behind the 6 automated phases.

Rust Security Gateway

widget_ui.pyd provides a zero-trust gateway: signature verification, encrypted config parsing, and anti-tamper protection. playstore_patcher_mem.pyd is the in-memory Play Store patcher SDK. Compiling to native Rust keeps the logic fast and hard to reverse.

Build Pipeline

• Nuitka compiles app.py → app.pyd (source protection)
• PyInstaller bundles into onedir
• Flet.exe patched with custom icon and version
• NSIS creates the final setup EXE with silent (/S) support

Why This Matters to Users

All of this engineering exists so that end users get one administrator-run wizard that 'just works' — no manual DISM, no ADB commands, no hunting for builds. That's the whole point of WSA Installer.