Need help with gamebuilder?
Click the “chat” button below for chat support from the developer who created it, or find similar developers for support.

About the developer

206 Stars 99 Forks Other 11 Commits 0 Opened issues


Game Builder is an application that allows users to create games with little or no coding experience.

Services available


Need anything else?

Contributors list

This project is no longer actively developed or maintained.

Game Builder

Game Builder

Welcome to the Game Builder open-source repository. This is the source code to build Game Builder, an application that allows users to create games with little or no coding experience. We are excited to share the source code with the community and are looking forward to seeing what you will create!

This is not an officially supported Google product.


  • Unity 2018.4.12f1

    It will probably work with later 2018.4.* versions, but this is the one we tested with. Unity 2019 is known to not work. If in doubt, use this exact version.

  • Python 2 to run code_gen scripts.

  • If you are using a Windows machine, you also need Git Bash (part of Git for Windows) to run shell scripts. If you are using a Mac, you don't need it: the built-in Terminal app is enough.

Running in Unity Editor

  1. Open the project (just the root of the repo).
  2. Open the splash screen scene:
  3. When the "TMP Importer" shows, click "Import TMP Essentials".
  4. Restart Unity.
  5. Click on the Play button.

Building the standalone EXE

To build a standalone, you must use the menu item

Game Builder
| Build
. Going through the normal Unity Build Settings window will not work. Once done, your build will be located under the

We have included a reference build (

). This is the build that you should get if you simply build a Windows standalone as-is, without enabling any extra plugins.

Scripting documentation

For documentation about how the in-game scripting works, open the

file in a browser (after downloading/cloning this repository).

Optional features

Game Builder was originally built using several Unity Asset Store plugins. We cannot include them in the repo, so by default the features that require them are disabled. However, we've set things up so it's easy to re-enable some features once you've purchased and imported some plugins (many are free!). Instructions for individual features are below.

Common instructions

  • Running shell scripts: Whenever these instructions mention that you must run a given shell script, it's implied that you must run it (e.g 'bash') in Git Bash (or OSX terminal) at the root of the repository.

  • Define a C# directive: When these instructions tell you to "define a C# directive" this means adding a C# #define symbol. To do this:

    • In Unity, open
      File | Build Settings
    • Go to
      Player Settings | Other Settings | Configuration
    • Add the directive to the end of the
      Scripting Define Symbols
      text field (with a semi-colon before it)
    • Restart Unity

Features that can be enabled for free

  • Photon Unity Networking - Enables multiplayer and collaborative-editing

    • NOTE: Because PUN integration is complex, we recommend you start with a fresh checkout of the codebase before following these steps. This reduces the likelihood of prefabs losing important property values after being edited without PUN.
    • First run the project as-is, freshly checked out, just to make sure it's working.
    • Don't forget to confirm TMPro's import dialog (import TMP Essentials).
    • Import the plugin from the Asset Store link above.
    • Define the directive
    • Close Unity before the next step
    • Run the shell script
    • Sign up for a PUN account (
    • In the PUN website, create a new application (type: Photon PUN)
    • Copy your new application's AppId.
    • Open the Unity project again and wait for importing to finish
    • Enter your AppId if prompted, but if not, go to the next step (the dialog might freeze while Unity imports assets, but don't worry, just wait until it finishes).
    • Finally, inspect the "PhotonServerSettings" asset and change the following:
      • "Hosting" to "Best Region"
      • "Regions" to "Everything"
      • Paste your AppId into the "AppId" field
    • Making sure it's all working:
      • After the above steps, make a build (
        Game Builder | Build
      • Run the build and create a private multiplayer game (
        New Project | Empty | Private MP
      • Run another instance (using the same build copy is fine) and join that game (
        Multiplayer | Use Join Code
      • Confirm that both "players" can run around as their robots (red and green), and that movements are seen by both.
      • Confirm that when one player scales an actor (like the text box), the other player sees the size change as well.
      • If these don't work, try this: In Unity's project window, inspect the Actor prefab. In its PhotonView component, does it have "ActorNetworking" as one of its "Observed components"? If it does not, then something went wrong, and you should start over with a fresh checkout.
  • Crosstales File Browser - Enables the system file browser UI for local disk import/export features

    • Import the plugin from the Asset Store link above.
    • Define the directive
  • Poly Toolkit for Unity

    To enable importing 3D models from Poly, you must enter an API Key for the Poly API.

    You do NOT need to import the Poly SDK (Poly Toolkit). It's already included. All you need to do is enter your API key.

    To do so, click the PtSettings.asset file in Unity (you will find it in Assets/third_party/PolyToolkit/Resources). The Inspector window will show several options for it. Click the RUNTIME tab, open the Auth Config section and enter your API Key, replacing the placeholder text "INSERT YOUR API KEY HERE".

    For instructions on how to get an API key, see the Google Cloud Console. When you create your Google Cloud Console project, don't forget to enable the Poly API on it before (not after) generating your API Key.

  • Google Image Search

    To enable Google Image Search in you Creation Library, you must setup a Custom Search Engine on Google Cloud Platform.

    (Instructions assume basic familiarity with Google Cloud)

    • Create a new project on Google Cloud Platform
    • Enable the “Custom Search API”
    • Create an API Key for the Custom Search API (via “Create Credentials”)
    • Inside the Unity project, paste the generated API key in to the
      variable at the top of GisSearchManager.cs
    • Go to the Custom Search Engine control panel ( and create a new search engine. When creating the search engine, enter any domain (we will delete it in the next step).
    • Edit the new search engine
      • Remove the site to search
      • Turn on “search the entire web”
      • Turn on “image search” and “safe search”
      • Inside the Unity project, copy the search engine's ID and paste it in to the searchID variable at the top of GisSearchManager.cs
    • You are all set!

Features that require premium plugins

  • 2D Shaper Library

    If you want game-generated 2D graphics (that is, you want to allow games to show HUD text, draw shapes on the screen, etc).

    • Import the plugin from the Asset Store link above.
    • Define the directive USESHAPER2D_LIBRARY.
  • Steam Workshop - If you are releasing on Steam and want to enable functionality like project sharing.

    • Import the plugin from the Asset Store link above.
    • Run the shell script "".
    • Define the directive USE_STEAMWORKS.
    • Find the file "steam_appid.txt" in the repo root (NOT the one in "redist"). Put your AppID in there (instead of 480).
  • TriLib - To import FBX files with animation from Poly.

    • Import the plugin from the Asset Store link above.
    • Define the directive USE_TRILIB.
  • Embedded Browser

    This plugin allows rendering of an HTML page inside of Game Builder, which enables you to use the Monaco-based code editor IDE.

    • Import the plugin from the Asset Store link above.
    • Define the directive
    • Run the shell script

Archival Build

In the

directory, you will also find the last build that we published to Steam (the
files). This differs from the open-source build because it has several optional plugins enabled such as 2D UI, rich JS editor, etc.


See the LICENSE file for more details.


This repository does not currently accept pull requests, but you are welcome to fork it to make your own version of it, if you want to.

We use cookies. If you continue to browse the site, you agree to the use of cookies. For more information on our use of cookies please see our Privacy Policy.