--- description: Compose pre-defined environment variables keywords: fig, composition, compose, docker, orchestration, cli, reference title: Change pre-defined environment variables redirect_from: - /compose/reference/envvars/ --- Compose already comes with pre-defined environment variables. This page contains information on how you can change the following pre-defined environment variables if you need to: - `COMPOSE_CONVERT_WINDOWS_PATHS` - `COMPOSE_FILE` - `COMPOSE_PROFILES` - `COMPOSE_PROJECT_NAME` - `DOCKER_CERT_PATH` - `COMPOSE_PARALLEL_LIMIT` - `COMPOSE_IGNORE_ORPHANS` - `COMPOSE_REMOVE_ORPHANS` - `COMPOSE_PATH_SEPARATOR` - `COMPOSE_ANSI` - `COMPOSE_STATUS_STDOUT` Compose also inherits common Docker CLI environment variables, such as `DOCKER_HOST` and `DOCKER_CONTEXT`. See [Docker CLI environment variable reference](/engine/reference/commandline/cli/#environment-variables) for details. ## Methods to override You can change the pre-defined environment variables: - Within your Compose file using the [`environment` attribute](set-environment-variables.md#use-the-environment-attribute) - With an [environment file](env-file.md) - From the command line - From your [shell](set-environment-variables.md#substitute-from-the-shell) When changing or setting any environment variables, be aware of [Environment variable precedence](envvars-precedence.md). ## Configure ### COMPOSE\_PROJECT\_NAME Sets the project name. This value is prepended along with the service name to the container's name on startup. For example, if your project name is `myapp` and it includes two services `db` and `web`, then Compose starts containers named `myapp-db-1` and `myapp-web-1` respectively. Compose can set the project name in different ways. The level of precedence (from highest to lowest) for each method is as follows: 1. The `-p` command line flag 2. `COMPOSE_PROJECT_NAME` 3. The top level `name:` variable from the config file (or the last `name:` from a series of config files specified using `-f`) 4. The `basename` of the project directory containing the config file (or containing the first config file specified using `-f`) 5. The `basename` of the current directory if no config file is specified Project names must contain only lowercase letters, decimal digits, dashes, and underscores, and must begin with a lowercase letter or decimal digit. If the `basename` of the project directory or current directory violates this constraint, you must use one of the other mechanisms. See also the [command-line options overview](../reference/index.md#command-options-overview-and-help) and [using `-p` to specify a project name](../reference/index.md#use--p-to-specify-a-project-name). ### COMPOSE\_FILE Specifies the path to a Compose file. Specifying multiple Compose files is supported. - Default behavior: If not provided, Compose looks for a file named `compose.yaml` or `docker-compose.yaml` in the current directory and, if not found, then Compose searches each parent directory recursively until a file by that name is found. - Default separator: When specifying multiple Compose files, the path separators are, by default, on: * Mac and Linux: `:` (colon), * Windows: `;` (semicolon). The path separator can also be customized using `COMPOSE_PATH_SEPARATOR`. Example: `COMPOSE_FILE=docker-compose.yml:docker-compose.prod.yml`. See also the [command-line options overview](../reference/index.md#command-options-overview-and-help) and [using `-f` to specify name and path of one or more Compose files](../reference/index.md#use--f-to-specify-name-and-path-of-one-or-more-compose-files). ### COMPOSE\_PROFILES Specifies one or more profiles to be enabled on `compose up` execution. Services with matching profiles are started as well as any services for which no profile has been defined. For example, calling `docker compose up`with `COMPOSE_PROFILES=frontend` selects services with the `frontend` profile as well as any services without a profile specified. * Default separator: specify a list of profiles using a comma as separator. Example: `COMPOSE_PROFILES=frontend,debug` This example enables all services matching both the `frontend` and `debug` profiles and services without a profile. See also [Using profiles with Compose](../profiles.md) and the [`--profile` command-line option](../reference/index.md#use---profile-to-specify-one-or-more-active-profiles). ### COMPOSE\_CONVERT\_WINDOWS\_PATHS When enabled, Compose performs path conversion from Windows-style to Unix-style in volume definitions. * Supported values: * `true` or `1`, to enable, * `false` or `0`, to disable. * Defaults to: `0`. ### COMPOSE\_PATH\_SEPARATOR Specifies a different path separator for items listed in `COMPOSE_FILE`. * Defaults to: * On MacOS and Linux to `:`, * On Windows to`;`. ### COMPOSE\_IGNORE\_ORPHANS When enabled, Compose doesn't try to detect orphaned containers for the project. * Supported values: * `true` or `1`, to enable, * `false` or `0`, to disable. * Defaults to: `0`. ### COMPOSE\_PARALLEL\_LIMIT Specifies the maximum level of parallelism for concurrent engine calls. ### COMPOSE\_ANSI Specifies when to print ANSI control characters. * Supported values: * `auto`, Compose detects if TTY mode can be used. Otherwise, use plain text mode. * `never`, use plain text mode. * `always` or `0`, use TTY mode. * Defaults to: `auto`. ### COMPOSE\_STATUS\_STDOUT When enabled, Compose writes its internal status and progress messages to `stdout` instead of `stderr`. The default value is false to clearly separate the output streams between Compose messages and your container's logs. * Supported values: * `true` or `1`, to enable, * `false` or `0`, to disable. * Defaults to: `0`. ## Unsupported in Compose V2 The environment variables listed below have no effect in Compose V2. For more information, see [Migrate to Compose V2](../migrate.md). - `COMPOSE_API_VERSION` By default the API version is negotiated with the server. Use `DOCKER_API_VERSION`. See the [Docker CLI environment variable reference](../../../engine/reference/commandline/cli/#environment-variables){:target="_blank" rel="noopener" class="_"} page. - `COMPOSE_HTTP_TIMEOUT` - `COMPOSE_TLS_VERSION` - `COMPOSE_FORCE_WINDOWS_HOST` - `COMPOSE_INTERACTIVE_NO_CLI` - `COMPOSE_DOCKER_CLI_BUILD` Use `DOCKER_BUILDKIT` to select between BuildKit and the classic builder. If `DOCKER_BUILDKIT=0` then `docker compose build` uses the classic builder to build images.