---
title: "Feature: #84153 - Introduce a generic Environment class"
manual: "TYPO3 Core Changelog"
version: "main"
permalink: "https://docs.typo3.org/permalink/changelog:feature-84153"
source: "Changelog/9.2/Feature-84153-IntroduceAGenericEnvironmentClass.rst"
typo3-version: "9.2"
typo3-major: 9
type: "feature"
issue: 84153
forge: "https://forge.typo3.org/issues/84153"
tags: ["PHP-API"]
rendered: "2026-09-20T18:31:11+00:00"
---

# Feature: #84153 - Introduce a generic Environment class {#feature-84153}

See [forge#84153](https://forge.typo3.org/issues/84153)

## Description {#description}

A new base API class `\TYPO3\CMS\Core\Core\Environment` has been added. This class contains application-wide
information related to paths and PHP internals, which were previously exposed via PHP constants.

This Environment class comes with a new possibility, to have a `config` and `var` folder outside of the document root
(known as `PATH_site`). When the environment variable `TYPO3_PATH_APP` is set, which defines the project root
folder, the new `config` and `var` folders outside of the document root are used for installation-wide configuration and
volatile files.

The following static API methods are exposed within the Environment class:

-   `Environment::isCli()` \- defines whether TYPO3 runs on a CLI context or HTTP context
-   `Environment::getApplicationContext()` \- returns the ApplicationContext object that encapsulates `TYPO3_CONTEXT`
-   `Environment::isComposerMode()` \- defines whether TYPO3 was installed via composer
-   `Environment::getProjectPath()` \- returns the absolute path to the root-level folder without the trailing slash
-   `Environment::getPublicPath()` \- returns the absolute path to the publicly accessible folder (previously known as PATH_site) without the trailing slash
-   `Environment::getVarPath()` \- returns the absolute path to the folder where non-public semi-persistent files can be stored. For regular projects, this is known as PATH_site/typo3temp/var
-   `Environment::getConfigPath()` \- returns the absolute path to the folder where (writeable) configuration is stored. For regular projects, this is known as PATH_site/typo3conf
-   `Environment::getCurrentScript()` \- the absolute path and filename to the currently executed PHP script
-   `Environment::isWindows()` \- whether TYPO3 runs on a windows server
-   `Environment::isUnix()` \- whether TYPO3 runs on a unix server

## Impact {#impact}

You should not rely on the PHP constants anymore, but rather use the Environment class to resolve paths:

-   `PATH_site`
-   `PATH_typo3conf`
-   `PATH_site . 'typo3temp/var/'`
-   `TYPO3_OS`
-   `TYPO3_REQUESTTYPE_CLI`
-   `PATH_thisScript`