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Where a game developer's disk goes: engines, libraries and build caches

Game engines install per version, projects keep generated libraries, and asset caches grow with every import. A map for Unity, Unreal, Godot and Blender users.

6 min read

Game development combines the largest installs of any kind of software with projects that generate gigabytes of intermediate files. Most of that is rebuildable, which is good news, if you know which folders.

The map

WhatTypical sizeRebuildable?Guide
Unity Editor, per version5 to 15 GB with modulesReinstallUnity projects
Unity project Library folder1 to 20 GBYes, on openUnity projects
Unreal Engine, per version40 GB and upReinstallgame launchers
Unreal DerivedDataCache, IntermediateGBs per projectYes
Blender projects and cachesvariesPartlyBlender
Xcode for Apple platformstens of GBBuild output, yeshow much space Xcode needs

The biggest wins

  1. Old engine versions. Unity Hub and the Epic launcher make it easy to install a version per project and hard to notice the total.
  2. Generated folders in projects you are not working on. Unity's Library and Unreal's DerivedDataCache, Intermediate, Saved and Binaries all regenerate.
  3. Platform modules you do not build for. Android, iOS, WebGL and console modules are each gigabytes.
du -sh /Applications/Unity/Hub/Editor/* 2>/dev/null | sort -h
find ~ -maxdepth 4 -type d -name Library -path '*Unity*' 2>/dev/null | xargs du -sh 2>/dev/null | sort -h
find ~ -maxdepth 5 -type d \( -name DerivedDataCache -o -name Intermediate \) 2>/dev/null | xargs du -sh 2>/dev/null | sort -h

Where the projects should live

Engines work well from a fast external SSD, and moving projects there frees the internal disk for the engine itself. The trade-offs are in external SSDs for developers, and the player side of games in Mac storage for gamers.

Related: Unity Asset Store cache taking up space on Mac.

Common questions

What takes the most space for game development on a Mac?

Engine installs, especially several versions of one engine, followed by generated project folders such as Unity's Library and Unreal's DerivedDataCache.

Is it safe to delete a Unity project's Library folder?

Yes, with Unity closed. Unity rebuilds it the next time the project opens, which takes a while for large projects.

Which Unreal project folders can be deleted?

DerivedDataCache, Intermediate, Saved and Binaries are regenerated. Keep Content, Config and Source.

How much space does a game engine need?

Unity is typically 5 to 15 GB per version with modules, and Unreal Engine 40 GB or more per version.

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