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Sync Details

This page aims to describe how Rojo turns files on the filesystem into Roblox objects.


Any directory on the filesystem will turn into a Folder instance in Roblox, unless that folder matches the name of a service or other existing instance. In those cases, that instance will be preserved.


Rojo can represent ModuleScript, Script, and LocalScript objects. The default script type is ModuleScript, since most scripts in well-structured Roblox projects will be modules.

File Name Instance Type
*.server.lua Script
*.client.lua LocalScript
*.lua ModuleScript

If a directory contains a file named init.server.lua, init.client.lua, or init.lua, that folder will be transformed into a *Script instance with the contents of the init file. This can be used to create scripts inside of scripts.

For example, this file tree:

  • my-game
    • init.client.lua
    • foo.lua

Will turn into these instances in Roblox:

Example of Roblox instances


Rojo supports a JSON model format for representing simple models. It's designed for instance types like BindableEvent or Value objects, and is not suitable for larger models.

Rojo JSON models are stored in .model.json files.

Starting in Rojo version 0.4.10, model files named init.model.json that are located in folders will replace that folder, much like Rojo's init.lua support. This can be useful to version instances like Tool that tend to contain several instances as well as one or more scripts.


In the future, Rojo will support .rbxmx models. See issue #7 for more details and updates on this feature.


Prior to Rojo version 0.4.9, the Properties and Children properties are required on all instances in JSON models!

JSON model files are fairly strict; any syntax errors will cause the model to fail to sync! They look like this:


    "Name": "hello",
    "ClassName": "Model",
    "Children": [
            "Name": "Some Part",
            "ClassName": "Part"
            "Name": "Some StringValue",
            "ClassName": "StringValue",
            "Properties": {
                "Value": {
                    "Type": "String",
                    "Value": "Hello, world!"