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 # Installation
 
-<!-- TODO: write document
+## Installing Godot Engine
 
-  This document should describe what the student needs to install
-  to allow working on the track on their local system using the CLI.
+The GDScript track is built on top of [Godot Engine][godot-engine], which runs on Windows, Linux, macOS, and Android.
+For the moment, the test runner for [working locally][working-locally] requires Linux.
+This track requires Godot version 4.0 or greater.
 
-  You can include the installation instructions in this document, but
-  usually it is better to link to a resource with the official installation
-  instructions, to prevent the instructions from becoming outdated.
+After completing the installation, you can verify if the CLI was installed successfully by running this command in a terminal:
 
-  The contents of this document are displayed on the track's documentation
-  page at `https://exercism.org/docs/tracks/<track>/installation`.
+```bash
+godot --version
+```
 
-  See https://exercism.org/docs/building/tracks/docs for more information. -->
+## Installing the Exercism GDScript track test runner
+
+You'll need [Godot installed][installation] correctly to use the test runner.
+
+To build and test GDScript scripts for Exercism, Godot will be run in "headless" mode from the CLI.
+These instructions currently require Linux and bash.
+
+### Step 1: Installing the overall test runner infrastructure
+
+To set up for testing, clone [https://github.com/exercism/gdscript-test-runner][gdscript-test-runner] and move its contents to `/opt/exercism/gdscript/test-runner/`:
+
+```sh
+git clone https://github.com/exercism/gdscript-test-runner.git
+sudo mv gdscript-test-runner/ /opt/exercism/gdscript/test-runner/
+```
+
+### Step 2: Downloading the single-exercise test runner script
+
+Assuming you have the `exercism` tool set up and have downloaded at least one GDScript exercise, it should have created a `gdscript` folder under your workspace (as shown by running `exercism configure`) to house the exercises.
+Save [the test runner][test-local-gdscript-solution] in this folder and mark the file executable.
+
+## Running tests
+
+With the installation steps done, you should be able start from any exercise directory (e.g., `~/exercism/gdscript/two-fer`) and run the script (living one level up, in `../`) to test your local solution to that exercise:
+
+```sh
+../test-local-gdscript-solution.sh
+```
+
+[installation]: https://exercism.org/docs/tracks/gdscript/installation
+[gdscript-test-runner]: https://github.com/exercism/gdscript-test-runner
+[test-local-gdscript-solution]: https://raw.githubusercontent.com/exercism/gdscript-test-runner/refs/heads/main/bin/test-local-gdscript-solution.sh
+
+## Using an IDE
+
+For features like syntax highlighting of GDScript files from, for example, [Visual Studio Code][vscode], you'll need an extension like [godot-tools][godot-tools] installed and activated, and a running debug server.
+When you open the Godot GUI and open a project, a debug server automatically runs in the background until you close the project or Godot.
+
+[godot-engine]: https://godotengine.org/
+[working-locally]: /docs/using/solving-exercises/working-locally.md
+[vscode]: https://code.visualstudio.com/download
+[godot-tools]: https://open-vsx.org/vscode/item?itemName=geequlim.godot-tools
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