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bdep - Man Page

project dependency manager


bdep --help
bdep --version
bdep help [command | topic]
bdep [common-options] command [command-options] command-args


The build2 project dependency manager is used to manage the dependencies of a project during development.

For a detailed description of any command or help topic, use the help command or see the corresponding man page (the man pages have the bdep- prefix, for example bdep-help(1)). Note also that command-options and command-args can be specified in any order and common-options can be specified as part of command-options.

A bdep project is a directory, normally under a version control system such as git(1), called project repository. A project contains one or more packages. If it contain several, then they are normally related, for example, the libhello library and the hello program.

Packages in a project may depend on other packages outside of the project. To distinguish between the two we call them project packages and dependency packages, respectively.  Naturally, our project packages may be someone else's dependency packages.

A simple, single-package project contains the package in the root of the project repository. For example (note the location of the package manifest and lockfile):

|-- .git/
|-- ...
|-- lockfile
`-- manifest

See Package Manifest (#manifest-package) for details on the manifest file.

If a project contains multiple packages or we wish to place the package into a subdirectory, then the root of the project repository must contain the packages.manifest file that specifies the package locations. For example:

|-- .git/
|-- hello/
|   |-- ...
|   |-- lockfile
|   `-- manifest
|-- libhello/
|   |-- ...
|   |-- lockfile
|   `-- manifest
`-- packages.manifest

For this project, packages.manifest would have the following contents:

: 1
location: hello/
location: libhello/

A project repository root would usually also contain the repositories.manifest file that lists the repositories that provide the dependency packages. For example:

|-- ...
|-- manifest
`-- repositories.manifest

If our hello project wanted to use libhello as a dependency package, then its repositories.manifest could look like this:

: 1
summary: hello project repository
role: prerequisite
location: https://example.com/libhello.git

See Repository List Manifest (#manifest-repository-list) for details on the repositories.manifest file.

For development a bdep project is associated with one or more bpkg(1) build configurations. These configuration are used as a backing for building project packages and their dependencies.

The list of the associated build configuration as well as the list of project packages initialized in each configuration are stored in the bdep project database under the .bdep/ subdirectory of the project root directory. For example:

hello-gcc/     # Build configuration for gcc.
hello-clang/   # Build configuration for clang.
|-- .bdep/
|-- .git/
`-- ...

The core of bdep functionality is state synchronization between the project and one or more associated build configurations. For example, if we list a new dependency in the package's manifest file, then bdep fetches and configures this dependency in a build configuration. Similarly, if we upgrade or downgrade a dependency in a build configuration, then bdep updates the corresponding entry in the package's lockfile.

A typical bdep workflow would consist of the following steps.

Obtain the Project

Normally we would use the version control system to obtain the project we want to develop:

$ git clone ssh://example.com/hello.git

Alternatively, we can use the bdep-new(1) command to start a new project (see Package Name (#package-name) for details on project naming):

$ bdep new -l c++ -t exe hello

Similar to version control tools, we normally run bdep from the project's directory or one of its subdirectories:

$ cd hello

See bdep-projects-configs(1) for alternative ways to specify the project location.

Initialize the Project

Next we use the bdep-init(1) command to create new or add existing build configurations and initialize our project in these configurations:

$ bdep init -C ../hello-gcc @gcc cc config.cxx=g++
$ bdep init -A ../hello-clang @clang

If the configuration directory is next to the project and its name is in the prj-name-cfg-name form, then the shortcut version of the init can be used instead:

$ bdep init -C @gcc cc config.cxx=g++
$ bdep init -A @clang

After initialization we can use the bdep-status(1) command to examine the status of our project in its configurations:

$ bdep status -a
in configuration @gcc:
hello configured 0.1.0-a.0.19700101000000

in configuration @clang:
hello configured 0.1.0-a.0.19700101000000

Most bdep commands operate on one or more build configurations associated with the project. If we don't specify one explicitly, then the default configuration (usually the first added; gcc in our case) is used. Alternatively, we can specify the configurations by name (if assigned), as directories, or with --all|-a (see bdep-projects-configs(1) for details). For example:

$ bdep status @clang @gcc      # by name
$ bdep status -c ../hello-gcc  # as a directory

If a command is operating on multiple configurations (like status -a in the previous example), then it will print a line identifying each configuration before printing the command's result.

By default the project's source directory is configured to forward to the default build configuration. That is, we can run the build system in the source directory and it will automatically build in the forwarded configuration as well as link the results back to the source directory using symlinks or another suitable mechanism (see bdep-config(1) for details). For example:

$ b        # build in gcc

$ ./hello  # run the result

Using the build system directly on configurations other than the default requires explicitly specifying their paths. To make this more convenient, the bdep-update(1), bdep-test(1), and bdep-clean(1) commands allow us to refer to them by names, perform the desired build system operation on several of them at once, and, in case of test, perform it on immediate or all dependencies or a project. For example:

$ bdep test @gcc @clang
in configuration @gcc:

in configuration @clang:

To deinitialize a project in one or more build configurations we can use the bdep-deinit(1) command. For example:

$ bdep deinit -a
Add, Remove, or Change Dependencies

Let's say we found libhello that we would like to use in our project. First we edit our project's repositories.manifest file and add the libhello's repository as our prerequisite:

$ cat repositories.manifest
role: prerequisite
location: https://example.com/libhello.git

Next we edit our manifest file and specify a dependency on libhello:

$ cat manifest
depends: libhello ^1.0.0

If we now run bdep-status(1), we will notice that a new iteration of our project is available for synchronization:

$ bdep status
hello configured 0.1.0-a.0.19700101000000
      available  0.1.0-a.0.19700101000000#1

See Package Version (#package-version) for details on package versions and iterations.

Synchronize the Project with Configurations

To synchronize changes in the project's dependency information with its build configurations we use the bdep-sync(1) command. Continuing with our example, this will result in libhello being downloaded and configured since our project now depends on it:

$ bdep sync
  build libhello/1.0.0 (required by hello)
  upgrade hello/0.1.0-a.0.19700101000000#1

$ bdep status -i
hello configured 0.1.0-a.0.19700101000000#1
  libhello ^1.0.0 configured 1.0.0

Note that by default build configurations are automatically synchronized on every build system invocation (see bdep-config(1) for details). As a result, we rarely need to run the sync command explicitly and instead can just run the desired build system operation (for instance, update or test) directly. For example:

$ b test
  build libhello/1.0.0 (required by hello)
  upgrade hello/0.1.0-a.0.19700101000000#1

It is also possible for several projects to share a build configuration. In this case all the projects are synchronized at once regardless of the originating project. For example, if we were also the authors of libhello and hosted it in a separate version control repository (as opposed to being a package in the hello repository), then it would have been natural to develop it together with hello in the same configurations:

$ cd ../libhello
$ bdep init -A ../hello-gcc @gcc
$ bdep sync  # synchronizes both hello and libhello
Upgrade or Downgrade Dependencies

The bdep-sync(1) command is also used to upgrade or downgrade dependencies (and it is also executed as the last step of init). Let's say we learned a new version of libhello was released and we would like to try it out.

To refresh the list of available dependency packages we use the bdep-fetch(1) command (or, as a shortcut, the -f flag to status):

$ bdep fetch

$ bdep status libhello
libhello configured 1.0.0 available [1.1.0]

Without an explicit version or the --patch|-p option, sync will upgrade the specified dependency to the latest available version:

$ bdep sync libhello
  upgrade libhello/1.1.0
  reconfigure hello/0.1.0

$ bdep status -i
hello configured 0.1.0-a.0.19700101000000#1
  libhello ^1.0.0 configured 1.1.0

Let's say we didn't like the new version and would like to go back to using the old one. To downgrade a dependency we have to specify its version explicitly:

$ bdep status -o libhello
libhello configured 1.1.0 available [1.0.0] (1.1.0)

$ bdep sync libhello/1.0.0
  downgrade libhello/1.1.0
  reconfigure hello/0.1.0


help [topic]

bdep-help(1) – show help for a command or help topic


bdep-new(1) – create and initialize new project


bdep-init(1) – initialize project in build configurations


bdep-sync(1) – synchronize project and build configurations


bdep-fetch(1) – fetch list of available project dependencies


bdep-status(1) – print status of project and/or its dependencies


bdep-ci(1) – submit project test request to CI server


bdep-release(1) – manage project's version during release


bdep-publish(1) – publish project to archive repository


bdep-deinit(1) – deinitialize project in build configurations


bdep-config(1) – manage project's build configurations


bdep-test(1) – test project in build configurations


bdep-update(1) – update project in build configurations


bdep-clean(1) – clean project in build configurations

Help Topics


bdep-common-options(1) – details on common options


bdep-projects-configs(1) – specifying projects and configurations


bdep-default-options-files(1) – specifying default options


bdep-argument-grouping(1) – argument grouping facility

Common Options

The common options are summarized below with a more detailed description available in bdep-common-options(1).


Print essential underlying commands being executed.


Print all underlying commands being executed.


Run quietly, only printing error messages.

--verbose level

Set the diagnostics verbosity to level between 0 and 6.

--stdout-format format

Representation format to use for printing to stdout.

--jobs|-j num

Number of jobs to perform in parallel.


Display progress indicators for long-lasting operations, such as network transfers, building, etc.


Suppress progress indicators for long-lasting operations, such as network transfers, building, etc.


Use color in diagnostics.


Don't use color in diagnostics.

--bpkg path

The package manager program to be used for build configuration management.

--bpkg-option opt

Additional option to be passed to the package manager program.

--build path

The build program to be used to build packages.

--build-option opt

Additional option to be passed to the build program.

--curl path

The curl program to be used for network operations.

--curl-option opt

Additional option to be passed to the curl program.

--pager path

The pager program to be used to show long text.

--pager-option opt

Additional option to be passed to the pager program.

--options-file file

Read additional options from file.

--default-options dir

The directory to load additional default options files from.


Don't load default options files.

Exit Status

Non-zero exit status is returned in case of an error.


The BDEP_DEF_OPT environment variable is used to suppress loading of default options files in nested bdep invocations. Its values are false or 0 to suppress and true or 1 to load.


Send bug reports to the users@build2.org mailing list.


June 2023 bdep 0.16.0