Vapor Activator

Selective Steam DLC manager using SmokeAPI and Koaloader.
Pick exactly which DLCs to unlock per game — no all-or-nothing.

Download

Platform	Link
Linux	vapor-activator
Windows	vapor-activator.exe

Features

• Detects installed Steam games from Flatpak, native Linux, and Windows paths
• Auto-detects Proton (32/64-bit) vs native Linux games
• EXE architecture detection — reads PE headers to determine 32/64-bit, deploys correct binaries
• MD5 fingerprinting — identifies already-installed SmokeAPI/Koaloader DLLs reliably
• Multi-source DLC discovery — Steam Store API + SteamCMD depot metadata + community hidden DLCs list
• Proxy mode (default): replaces steam_api*.dll / libsteam_api.so — no launch args needed
• Hook mode: injects via version.dll / winhttp.dll / winmm.dll / dinput8.dll / d3d11.dll / dxgi.dll for games that integrity-check the Steam API DLL
• Koaloader mode: full DLL sideloading — proxy DLL forwards calls to the real system DLL while loading SmokeAPI as a module. Original steam_api.dll is never touched. Note: Koaloader performs DLL injection, which may trigger antivirus false positives on Windows — this is expected behavior, not malware.
• Reads existing SmokeAPI configs from prior manual or tool-based installs
• Clean removal with original file restoration, hook cleanup, and Koaloader config removal
• Auto-downloads SmokeAPI and Koaloader from GitHub releases
• Configurable Steam library path, persisted across sessions

Build from source

Requires Rust.

cargo build --release
./target/release/vapor-activator      # Linux
target\release\vapor-activator.exe    # Windows

Usage

1. Set Steam library folder — the folder containing steamapps/ (auto-detected, change with Change...)

2. Download tools — click Get next to SmokeAPI and Koaloader in the left panel. Cached at:

   Platform	Cache path
   Linux	~/.cache/vapor-activator/smokeapi/ and .../koaloader/
   Windows	%LOCALAPPDATA%\vapor-activator\smokeapi\ and ...\koaloader\

3. Select a game from the list — shows type, architecture, and install status

4. Choose method:

   • Proxy (default) — renames original steam_api*.dll → _o.dll, copies SmokeAPI in its place. Works for most games.
   • Hook — leaves original untouched, places SmokeAPI as version.dll (or another selected DLL). For games that verify DLL integrity.
   • Koaloader — full sideload: the proxy DLL forwards all calls to the real system DLL while loading SmokeAPI silently. The original file is never checked.

5. Check the DLCs you want unlocked — unchecked DLCs stay at real ownership

6. Apply & Install

7. Launch the game normally through Steam

Removing

Select the game and click Remove SmokeAPI. Restores original files, cleans up hook DLLs, Koaloader configs, and SmokeAPI configs.

Config

Steam library path saved to:

Platform	Path
Linux	~/.config/vapor-activator/config.json
Windows	%APPDATA%\vapor-activator\config.json

How it works

SmokeAPI intercepts Steamworks SDK calls (BIsSubscribedApp, GetDLCCount, etc.) and reports DLCs as owned/unowned based on SmokeAPI.config.json. In Koaloader mode, the proxy DLL loads the real system DLL, forwards every call, and also loads SmokeAPI as a module — the game never sees the real steam_api.dll being touched.

License

MIT

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Built with the help of OpenCode