> ## Documentation Index > Fetch the complete documentation index at: https://developer.upsun.com/llms.txt > Use this file to discover all available pages before exploring further. # Single-runtime image > See all of the options for controlling your apps and how they're built and deployed on Upsun Cloud. Use the `.upsun/config.yaml` file, located at the root of your Git repository, to configure the apps in a single-runtime image. See a [comprehensive example](https://developer.upsun.com/docs/configure-apps#comprehensive-example) of a configuration in a `.upsun/config.yaml` file. [Multi-app projects](https://developer.upsun.com/docs/configure-apps/multi-app) can be set up in various ways. ## Primary application properties In the `.upsun/config.yaml` file, configure each application as a unique key beneath the top-level `applications` key. For example, if your deployed site requires a Javascript `frontend` application container and a Python `backend` application container, the `.upsun/config.yaml` file would start to look something like this: applications: frontend: type: 'nodejs:\{\{version:nodejs:latest}}' \# Additional frontend configuration backend: type: 'python:\{\{version:python:latest}}' \# Additional backend configuration The following table presents all of the properties available to each unique app beneath the `applications` key. The **Set in instance** column defines whether the given property can be overridden within a `web` or `workers` instance. To override any part of a property, you have to provide the entire property. > [!NOTE] > > The `build`, `dependencies`, and `runtime` properties are unique to this image type and are described later in this topic. All other properties are available in both single-runtime and composable images — click a property name to view its details in a separate topic. | Name | Type | Required | Set in instance? | Description | | - | - | - | - | - | | [`type`](#type) | A type | Yes | No | The base image to use with a specific app language. Format: `runtime:version`. | | [`container_profile`](https://developer.upsun.com/docs/configure-apps/image-properties/container_profile) | A container profile | | Yes | Determines which combinations of CPU and RAM a container can use. | | [`relationships`](https://developer.upsun.com/docs/configure-apps/image-properties/relationships) | A dictionary of relationships | | Yes | Connections to other services and apps. | | [`mounts`](https://developer.upsun.com/docs/configure-apps/image-properties/mounts) | A dictionary of mounts | | Yes | Directories that are writable even after the app is built. Allocated disk for mounts is defined with a separate resource configuration call using `upsun resources:set`. | | [`web`](https://developer.upsun.com/docs/configure-apps/image-properties/web) | A web instance | | N/A | How the web application is served. | | [`workers`](https://developer.upsun.com/docs/configure-apps/image-properties/workers) | A worker instance | | N/A | Alternate copies of the application to run as background processes. | | [`timezone`](https://developer.upsun.com/docs/configure-apps/timezone) | `string` | | No | The timezone for crons to run. Format: a [TZ database name](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones). Defaults to `UTC`, which is the timezone used for all logs no matter the value here. See also [app runtime timezones](https://developer.upsun.com/docs/projects/change-project-timezone.md) | | [`access`](https://developer.upsun.com/docs/configure-apps/image-properties/access) | An access dictionary | | Yes | Access control for roles accessing app environments. | | [`variables`](https://developer.upsun.com/docs/configure-apps/image-properties/variables) | A variables dictionary | | Yes | Variables to control the environment. | | [`build`](#build) | A build dictionary | | No | What happens when the app is built. | | [`dependencies`](#dependencies) | A dependencies dictionary | | No | What global dependencies to install before the `build` hook runs. | | [`hooks`](https://developer.upsun.com/docs/configure-apps/image-properties/hooks) | A hooks dictionary | | No | What commands run at different stages in the `build`, `deploy`, and `post_deploy` phases. | | [`crons`](https://developer.upsun.com/docs/configure-apps/image-properties/crons) | A cron dictionary | | No | Scheduled tasks for the app. | | [`source`](https://developer.upsun.com/docs/configure-apps/image-properties/source) | A source dictionary | | No | Details about the app’s source code and available operations. | | [`runtime`](#runtime) | A runtime dictionary | | No | Customizations to your PHP runtime. | | [`additional_hosts`](https://developer.upsun.com/docs/configure-apps/image-properties/additional_hosts) | An additional hosts dictionary | | Yes | Mappings of hostnames to IP addresses. | | [`authorizations`](https://developer.upsun.com/docs/configure-apps/image-properties/authorizations) | | An authorizations dictionary | Yes | An authorizations list that grants applications and tasks narrowly-scoped access to the environment API and task operations. | | [`operations`](https://developer.upsun.com/docs/configure-apps/runtime-operations) | A dictionary of runtime operations | | No | Runtime operations for the application. | ## Root directory Some of the properties you can define are relative to your app's root directory. The root defaults to the root of the repository. applications: frontend: type: 'nodejs:\{\{version:nodejs:latest}}' \# Default behavior of source.root source: root: "/" That is, if a custom value for `source.root` is not provided in your configuration, the default behavior is equivalent to the above. To specify another directory, for example for a [multi-app project](https://developer.upsun.com/docs/configure-apps/multi-app), use the [`source.root` property](https://developer.upsun.com/docs/configure-apps/image-properties/source). ## `type` > [!NOTE] > > To install *multiple* runtimes and tools in your application container, use the Upsun Cloud composable image.\\ > > If you arrived here from another page, you may want to review the supported `stack` key where `type` was referenced.\\ > > For details, see the list of [supported Nix runtimes](https://developer.upsun.com/docs/configure-apps/app-reference/composable-image.md#upsun-supported-nix-runtimes) that you can define in a composable image `stack`. The `type` defines the base container image used to run the application. The version is the major (`X`) and sometimes minor (`X.Y`) version numbers, depending on the service, as in the following table. Security and other patches are taken care of for you automatically. Available languages and their supported versions: | Language | Type key | Supported versions | | - | - | - | | [C#/.Net Core](https://developer.upsun.com/docs/languages/dotnet.md) | `dotnet` | 10.0 8.0 | | [Elixir](https://developer.upsun.com/docs/languages/elixir.md) | `elixir` | 1.20 1.19 1.18 | | [FrankenPHP](https://developer.upsun.com/docs/languages/php/frankenphp.md) | `frankenphp` | 1.8.5 1.8.4 1.8.3 1.8.2 | | [Go](https://developer.upsun.com/docs/languages/go.md) | `golang` | 1.27 1.26 | | [Java](https://developer.upsun.com/docs/languages/java) | `java` | 25 21 | | [JavaScript/Node.js](https://developer.upsun.com/docs/languages/nodejs) | `nodejs` | 26 24 22 | | [PHP](https://developer.upsun.com/docs/languages/php) | `php` | 8.5 8.4 8.3 8.2 | | [Python](https://developer.upsun.com/docs/languages/python) | `python` | 3.14 3.13 3.12 3.11 | | [Ruby](https://developer.upsun.com/docs/languages/ruby.md) | `ruby` | 4.0 3.4 3.3 | | [Rust](https://developer.upsun.com/docs/languages/rust.md) | `rust` | 1 | ### Example configuration These are used in the format `runtime:version`: applications: \: type: 'php:\{\{version:php:latest}}' ## `build` The only property of the `build` dictionary is `flavor`, which specifies a default set of build tasks to run. Flavors are language-specific. See what the build flavor is for your language: * [Node.js](https://developer.upsun.com/docs/languages/nodejs#dependencies) * [PHP](https://developer.upsun.com/docs/languages/php#dependencies) In all languages, you can also specify a flavor of `none` to take no action at all (which is the default for any language other than PHP and Node.js). applications: \: source: root: "/" type: 'nodejs:\{\{version:nodejs:latest}}' build: flavor: none ## `dependencies` Installs global dependencies as part of the build process. They're independent of the code dependencies of your application and are available in the `PATH` during the build process and in the runtime environment. They're installed before the `build` hook runs using a package manager for the language. | Language | Key name | Package manager | | - | - | - | | PHP | `php` | [Composer](https://getcomposer.org/) | | Python 2 | `python` or `python2` | [Pip 2](https://packaging.python.org/tutorials/installing-packages/) | | Python 3 | `python3` | [Pip 3](https://packaging.python.org/tutorials/installing-packages/) | | Ruby | `ruby` | [Bundler](https://bundler.io/) | | Node.js | `nodejs` | [npm](https://www.npmjs.com/) (see [how to use yarn](https://developer.upsun.com/docs/languages/nodejs#use-yarn-as-a-package-manager)) | The format for package names and version constraints are defined by the specific package manager. An example of dependencies in multiple languages: applications: \: type: 'nodejs:\{\{version:nodejs:latest}}' source: root: "/" dependencies: php: # Specify one Composer package per line. drush/drush: '8.0.0' python2: # Specify one Python 2 package per line. behave: '\*' requests: '\*' python3: # Specify one Python 3 package per line. numpy: '\*' ruby: # Specify one Bundler package per line. sass: '3.4.7' nodejs: # Specify one NPM package per line. pm2: '^4.5.0' ## `runtime` This applies to PHP only. The following table lists the various possible modifications to your PHP runtime: | Name | Type | Language | Description | | - | - | - | - | | `extensions` | List of `string`s OR [extensions definitions](#extensions) | PHP | [PHP extensions](https://developer.upsun.com/docs/languages/php/extensions.md) to enable. | | `disabled_extensions` | List of `string`s | PHP | [PHP extensions](https://developer.upsun.com/docs/languages/php/extensions.md) to disable. | | `request_terminate_timeout` | `integer` | PHP | The timeout (in seconds) for serving a single request after which the PHP-FPM worker process is killed. | | `sizing_hints` | A [sizing hints definition](#sizing-hints) | PHP | The assumptions for setting the number of workers in your PHP-FPM runtime. | | `xdebug` | An Xdebug definition | PHP | The setting to turn on [Xdebug](https://developer.upsun.com/docs/languages/php/xdebug.md). | You can also set your [app's runtime timezone](https://developer.upsun.com/docs/configure-apps/timezone.md). ### Extensions > [!NOTE] > > To install multiple runtimes and tools in your application container, use the Upsun Cloud composable image.\\ > > If you arrived here from another page and you are using the composable image, you enable and disable extensions by using the `stack.runtimes.extensions`/`stack.runtimes.disabled_extensions` keys.\\ > > For details and an example, see the [`stack`](https://developer.upsun.com/docs/configure-apps/app-reference/composable-image#stack) section in the "Composable image" topic. You can enable [PHP extensions](https://developer.upsun.com/docs/languages/php/extensions.md) just with a list of extensions: applications: \: type: 'php:\{\{version:php:latest}}' source: root: "/" runtime: extensions: \- geoip \- tidy Alternatively, if you need to include configuration options, use a dictionary for that extension: applications: \: type: 'php:\{\{version:php:latest}}' source: root: "/" runtime: extensions: \- geoip \- name: blackfire configuration: server\_id: \ server\_token: \ In this case, the `name` property is required. ### Sizing hints The following table shows the properties that can be set in `sizing_hints`: | Name | Type | Default | Minimum | Description | | - | - | - | - | - | | `request_memory` | `integer` | 45 | 10 | The average memory consumed per request in MB. | | `reserved_memory` | `integer` | 70 | 70 | The amount of memory reserved in MB. | See more about [PHP-FPM workers and sizing](https://developer.upsun.com/docs/languages/php/fpm.md). ## Resources (CPU, memory, and disk space) By default, Upsun Cloud assigns a container profile and container size to each application and service on the first deployment of a project. \ The container *profile* defines and enforces a specific CPU-to-memory ratio. The default container profile for an app or service in a composable image is `HIGH_CPU`. Use the Upsun Cloud CLI or Console to manually adjust the allocated container *size* (CPU and memory resources)—that is, to perform a **vertical‑scaling** action. When you redeploy, the container runs with the CPU‑to‑memory ratio defined by its profile, so it enforces the size you specified. Related topics: * For detailed steps for changing the container size, see the [Vertical scaling](https://developer.upsun.com/docs/manage-resources/adjust-resources.md#vertical-scaling) section of the "Resource configuration topic. * For details about container sizes for each resource allocation strategy (shared CPU, guaranteed CPU, and initial allocation), see the [Advanced: Container profiles](https://developer.upsun.com/docs/manage-resources/adjust-resources.md#advanced-container-profiles) section of the "Resource configuration" topic. * To learn more about general resource management in Upsun Cloud, see the topics in the [Manage resources](https://developer.upsun.com/docs/manage-resources.md) section. ### Downsize a disk You can reduce the target disk size of an app. Keep in mind: * Backups created before the downsize are incompatible and cannot be used; you must [create new backups](https://developer.upsun.com/docs/environments/backup.md). * The downsize will fail if the disk contains more data than the target size. ### Combine single-runtime and composable images In a [multiple application context](https://developer.upsun.com/docs/configure-apps/multi-app), you can use a mix of single-runtime images and [composable images](https://developer.upsun.com/docs/configure-apps/app-reference/composable-image.md). The following sample configuration includes two applications: * `frontend` – uses a single-runtime image * `backend` – uses a composable image\ In this app, PHP is the primary runtime and is started automatically (PHP-FPM also starts automatically when PHP is the primary runtime). For details, see the [PHP as a primary runtime](https://developer.upsun.com/docs/configure-apps/app-reference/composable-image.md#php-as-a-primary-runtime) section in the Composable image topic. applications: frontend: \# this app uses the single-runtime image with a specific node.js runtime type: 'nodejs:\{\{version:nodejs:latest}}' backend: \# this app uses the composable image and specifies two runtimes type: "composable:\{\{version:composable:latest}}" stack: runtimes: \- "php\@8.4": extensions: \- apcu \- sodium \- xsl \- pdo\_sqlite \- "python\@3.13" packages: \- "python313Packages.yq" # python package specific This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.