---
title: "Installation"
manual: "Frontend Theme for Extension Development"
version: "1.0"
source: "Installation/Index.rst"
rendered: "2026-09-30T14:57:50+00:00"
---

# Installation {#installation}

The extension has to be installed like any other TYPO3 CMS extension.

> [!WARNING]
> This is a development tool, not a production theme. It belongs in a
> development or test instance, not in a live site — that applies to every
> installation method described below.

## Composer mode {#composer-mode}

Being a development tool, it usually belongs in `require-dev` — of the
extension repository whose frontend is to be looked at, or of the test instance
set up for it:

```bash
composer require --dev sbuerk/theme-extension-development
```

A TYPO3 extension required that way is installed and activated exactly like any
other one, because `typo3/cms-composer-installers` makes no distinction
between `require` and `require-dev`. A deployment installing with
`composer install --no-dev` simply leaves it out, which is the point.

> [!NOTE]
> As long as no stable version has been released, the development version of
> the `1` branch has to be required explicitly:
>
> ```bash
> composer require --dev sbuerk/theme-extension-development:^1.0@dev
> ```
>
> This additionally requires `minimum-stability` to be set to `dev`
> together with `prefer-stable` set to `true` in the root
> `composer.json` file.

## Classic mode {#classic-mode}

1.  **Get it from the Extension Manager**:
    Switch to the module **Admin Tools > Extensions**, switch to
    **Get Extensions** and search for the extension key
    *theme_extension_development*, then import the extension from the repository.
1.  **Get it from typo3.org**:
    You can always get the current version from [TER](https://extensions.typo3.org/extension/theme_extension_development) by downloading the zip
    version. Upload the file afterwards in the Extension Manager.

Installing the extension does not render anything yet. The theme still has to
be enabled for a site — see [Configuration](../Configuration/Index.html#configuration).