re-won-launcher-1792

This is a source-level reconstruction of the WON-era Half-Life launcher, build 1792 compiled Sep 20 2001, protocol version 1.1.0.8. This project aims to recereate the original launcher sources for archival & historical reasons and aims to bring various improvements and bug fixes over the original version of the launcher.

This project has been reversed 95% by using LLMs and agent orchestration in a matter of 2 months. By utilizing advanced agent orchestration techniques and custom-crafted prompts, it was possible to reconstruct the imaginatory style of the code the original launcher might've once had by an acceptable margin. While I personally love reversing, the introduction of LLMs and agentic workflows has helped me to create projects like this one, because the agents significantly speedup the process of reversing I would need do by hand, painfuly slowly.

While there's no build of the launcher with debug symbols we know of, there are various sources from where we can gather extra information about the code:

• RTTI for class names.
• NetGame.exe launcher for a bunch of file names.
• The fact that the linker puts source files in chronological order sorted alphabetically into the binary helps us to deduce file names more accurately.
• Quake sources, since this code has a bunch of overlap.

Using a combination of such sources we are able to guess how did the original code look like, with some accuracy.

Fixes

This is a list of fixes this project implements:

• More video modes resolutions: The video modes dialog now have more resolutions available.
• Window title bar: In Windowed mode, the launcher is now a full-fledged window with a title bar and no new windows when selecting sub menus.
• Working fullscreen: In Fullscreen mode the launcher fills the screen again instead of sitting in a small window in the corner.
• Prompts open on the launcher: Message boxes and prompts are centred on the launcher window instead of in the middle of the screen.
• Remembered window position: In Windowed mode the launcher reopens where you last dragged it.
• Mouse wheel scrolling: The wheel now scrolls whatever list, drop-down or scrollbar the pointer is over.
• Keyboard list navigation: The arrow keys, Page Up/Down, Home and End move the selection in a list, and Enter opens it.

Installation

The original launcher carries out several dependencies such as vgui.dll, or the WON DLLs such as WONCrypt.dll or WONAuth.dll. For easy installation, by default, we bundle these DLLs into the launcher executable itself. This is also why the executable is bigger than the original file (among other factors).

The installation is merely about copying the hl.exe file into the Half-Life folder and launching it.

Which versions of Half-Life are supported?

Short answer: Only Half-Life 1.1.0.8, the final WON release from September 2001, is supported. This is the version of the game we used to reconstruct the source.

In the old versions of the game, backwards compatibility is not established due to various factors such as incompatible DLL dependencies, engine interface differences, and so on. Therefore other versions of the game are not compatible with this source reconstruction.

WON Server Emulation

Part of the reconstruction was also a WON server emulation. Since some of the pages such as Chat Rooms or Internet Games are technically not easily testable because WON servers are down, an emulator has also been built which allowed me to visually confirm and test these pages.

The emulator can be found at wonserver/.

Quick start:

1. Build the project (see below); wonserverd.exe builds along with hl.exe.
2. Run wonserverd.exe once from the folder you want it to keep its keys in. It generates verifier.key, auth.key and kver.kp on first start (this can take about a minute).
3. Copy the generated kver.kp into your Half-Life folder, replacing the original — the launcher uses it to trust the emulator's certificates.
4. Point every block in the Half-Life folder's woncomm.lst at 127.0.0.1. See wonserver/README.md
5. Keep wonserverd.exe running, then launch hl.exe as normal.

Building

Prerequisites

• Visual Studio 2026 (toolset v145) with the following components:
  • Desktop development with C++
  • C++ MFC for v145 build tools (x86 & x64)
  • C++ MFC for v145 build tools with Spectre mitigations is not required, but the MBCS MFC libraries are — install C++ MFC for ... (MBCS) (the launcher is a MultiByte, not Unicode, MFC app).
  • A Windows 10/11 SDK (provides winmm.lib, ddraw.lib, dxguid.lib).
• CMake ≥ 3.25.
• Win32 (x86) — the entire reconstruction is 32-bit.

Setup

cmake -S . -B build -G "Visual Studio 18 2026" -A Win32
cmake --build build --config Debug

If your CMake doesn't yet know the 2026 generator, use the 2022 generator with the v145 toolset:

cmake -S . -B build -G "Visual Studio 17 2022" -A Win32 -T v145
cmake --build build --config Debug

Open build/re-won-launcher-1792.sln to develop in the IDE; hl is set as the startup project.

Deploying to a game folder

Copy halflife_path.txt.example to halflife_path.txt and point it at your WON-era Half-Life install. After that, every build copies hl.exe (and the WON DLLs) into that folder automatically, and F5 in Visual Studio launches the deployed copy directly. Skip this file and the build still works — it just leaves the binaries in build/<config>/ for you to copy manually.