Mamba

mamba is a CLI tool to manage conda s environments.

If you already know conda, great, you already know mamba!

If you’re new to this world, don’t panic you will find everything you need in this documentation. We recommend to get familiar with concepts first.

Quickstart

The mamba create command creates a new environment.

You can create an environment with the name nameofmyenv by calling:

mamba create -n nameofmyenv <list of packages>

After this process has finished, you can _activate_ the virtual environment by calling mamba activate <nameofmyenv>. For example, to install JupyterLab from the conda-forge channel and then run it, you could use the following commands:

mamba create -n myjlabenv jupyterlab -c conda-forge
mamba activate myjlabenv  # activate our environment
jupyter lab               # this will start up jupyter lab and open a browser

Once an environment is activated, mamba install can be used to install further packages into the environment.

mamba activate myjlabenv
mamba install bqplot  # now you can use bqplot in myjlabenv
mamba install "matplotlib>=3.5.0" cartopy  # now you installed matplotlib with version>=3.5.0 and default version of cartopy

mamba vs conda CLIs

mamba is a drop-in replacement and uses the same commands and configuration options as conda.

You can swap almost all commands between conda & mamba:

mamba install ...
mamba create -n ... -c ... ...
mamba list

Repoquery

mamba comes with features on top of stock conda. To efficiently query repositories and query package dependencies you can use mamba repoquery.

Here are some examples:

# will show you all available xtensor packages.
$ mamba repoquery search xtensor

# you can also specify more constraints on this search query
$ mamba repoquery search "xtensor>=0.18"

# will show you a list of the direct dependencies of xtensor.
$ mamba repoquery depends xtensor

# will show you a list of the dependencies (including dependencies of dependencies).
$ mamba repoquery depends xtensor --recursive

The flag --recursive shows also recursive (i.e. transitive) dependencies of dependent packages instead of only direct dependencies. With the -t,--tree flag, you can get the same information of a recursive query in a tree.

$ mamba repoquery depends -t xtensor

xtensor == 0.21.5
├─ libgcc-ng [>=7.3.0]
│ ├─ _libgcc_mutex [0.1 conda_forge]
│ └─ _openmp_mutex [>=4.5]
│   ├─ _libgcc_mutex already visited
│   └─ libgomp [>=7.3.0]
│     └─ _libgcc_mutex already visited
├─ libstdcxx-ng [>=7.3.0]
└─ xtl [>=0.6.9,<0.7]
    ├─ libgcc-ng already visited
    └─ libstdcxx-ng already visited

And you can ask for the inverse, which packages depend on some other package (e.g. ipython) using whoneeds.

$ mamba repoquery whoneeds ipython

Name            Version Build          Depends          Channel
-------------------------------------------------------------------
jupyter_console 6.4.3   pyhd3eb1b0_0   ipython          pkgs/main
ipykernel       6.9.1   py39haa95532_0 ipython >=7.23.1 pkgs/main
ipywidgets      7.6.5   pyhd3eb1b0_1   ipython >=4.0.0  pkgs/main

With the -t,--tree flag, you can get the same information in a tree.

$ mamba repoquery whoneeds -t ipython

ipython[8.2.0]
├─ jupyter_console[6.4.3]
│  └─ jupyter[1.0.0]
├─ ipykernel[6.9.1]
│  ├─ notebook[6.4.8]
│  │  ├─ widgetsnbextension[3.5.2]
│  │  │  └─ ipywidgets[7.6.5]
│  │  │     └─ jupyter already visited
│  │  └─ jupyter already visited
│  ├─ jupyter_console already visited
│  ├─ ipywidgets already visited
│  ├─ jupyter already visited
│  └─ qtconsole[5.3.0]
│     └─ jupyter already visited
└─ ipywidgets already visited

Note

depends and whoneeds sub-commands require either the specified package to be installed in you environment, or for the channel to be specified with the -c,--channel flag. When search sub-command is used without specifying the channel explicitly (using the flag previously mentioned), the search will be performed considering the channels set during the configuration.