Faster decompression (updated)
Fallout 4’s asset loading speeds up by replacing the game’s outdated zlib 1.2.7 decompression library with a more modern, optimized alternative. Universal plug-in, supporting "Fallout London", AE and VR.
Screenshots 1 screenshots
About this mod Machine translation
Fallout 4’s asset loading speeds up by replacing the game’s outdated zlib 1.2.7 decompression library with a more modern, optimized alternative. Universal plug-in, supporting "Fallout London", AE and VR.
Original address:
Prefix:
Fallout 4 Script Extender (F4SE)：
Fallout 4 Script Extender VR (F4SEVR) (optional, if you want to use it on the VR version):
Updated on September 9th:
Version 1.4.1
Detect Addicol bLibFlatate = true setting, if so disable the module with warning
Version 1.4
Added support for 1.11.240
Added lazy decompression initialization to reduce unnecessary memory allocation
Improved streaming capabilities and compatibility with game save load memory allocators
Update libdeflate to 1.26, zlib-ng to 2.3.3, LZ4 to 1.10.0
Updated on May 28th:
Version 1.3
- Remove address library dependency
- Removed AVX2 flag to be compatible with older systems
Updated on March 18th:
Version 1.2
- Update Libdeflate version to 1.25
- Replace call end wiring with auto-detection and Detours
- Added ini option for passthrough mode
Version 1.1
-Fixed the issue of module logs going to the wrong directory
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What does it do?
Every time Fallout 4 loads textures, meshes, sounds, or any other assets from BA2, it needs to be unzipped first. The game uses zlib version 1.2.7 released in 2012. FastDecompress intercepts these decompression calls and redirects them to the more modern zlib-ng and libdeflate libraries.
Compatibility with Addicol: FastDecompress uses libfllate to process form decompression, similar to Addictol, and adds zlib-ng for live expansion, which Addictol does not involve. There is no harm in using two free-deflating hooks at the same time.
FastDecompress is a single DLL software available for all three Fallout 4 runtimes: OG, AE, and VR.
How to use
Install mod
game
Enjoy faster decompression
Acknowledgments
Mod inspiration:
WallsoBG - Zlib Update
Framework and decompression:
F4SE Team - Fallout 4 Script Expander
Ryan McKenzie（powerof3） - CommonLibF4
alandtse (Alan Tse) - CommonLibF4 fork that supports unified OG/NG/VR in a single DLL
zlib-ng Contributor - zlib-ng
Install & use Install: follow the bundled instructions
- Unzip the archive from playbuff and read the bundled readme / instructions first.
- There is no universal mod manager for this game: some mods replace game files directly, some go into a game-specific Mods folder, and some need a game-specific community loader or tool first — follow the bundled readme.
- Place the files exactly as the readme says; mods with listed dependencies need those installed too.
- Launch the game to confirm it loaded; some games require enabling mods in settings or an in-game mod menu.
Install locations vary a lot between games and mods — the bundled readme is the most reliable guide.