Micromamba on Windows 10

Summary:

There's nothing more fun than setting up Python environments and packages. I started using Micromamba after getting angry at a previous mamba/conda/WSL installation (self-induced pain/complication). I wanted to try it in hopes of finding a simpler python environment config with steps I could share/automate with my other enterprisey team members.

5-ish Ws for this guide

What: Microconda installation
Who: Anyone in need of a simple Python env configuration
Where: Windows 10 / PowerShell

A. Delete existing Conda/Mamba or related libraries

1. Remove Anaconda and/or Mambaforge from Windows Programs

2. Delete .condarc/.mambarc files from $HOME directory if no longer needed

B. Download and configure micromamba directory

1. Open Powershell as administrator (not to be confused with Windows Powershell)

2. Create the new directory for Micromamba

   • For example: mkdir \micromamba or mkdir ~\micromamba

3. Navigate to the new directory cd \micromamba

4. Download the latest Windows binaries

    Invoke-Webrequest -URI https://micro.mamba.pm/api/micromamba/win-64/latest -OutFile micromamba.tar.bz2
   

5. Extract micromamba using 7-zip (or preferred unzip tool)

    7z e micromamba.tar.bz2 && 7z x micromamba.tar && MOVE -Force Library\bin\micromamba.exe micromamba.exe
   

   ```

Script Details

- Decompress the tarball 7z e micromamba.tar.bz2
- Extract the tarball 7z x micromamba.tar
- Move micromamba.exe to root MOVE -Force Library\bin\micromamba.exe micromamba.exe

1. Cleanup

   • You can delete the Library folder, .tar, and .tar.bz2 files now

   • Close Powershell

2. Create new MAMBA_ROOT_PREFIX env variable and add new folder to PATH env variable example instructions

   • Control Panel -> Edit System Environment Variables -> Environment Variables

   • Verify changes in new Powershell with following command micromamba -v

C. Configure Micromamba for Powershell

1. Open Powershell as admin

2. Run following init script micromamba shell init -s powershell

   • This will create or update powershell profile at Powershell location

     - E.g. C:\Users\_YourUserName_\Documents\PowerShell\profile.ps1

3. Create a new python virtual environment (I prefer the .yml config file route)

   • Create new yml config file in micromamba folder

           name: new-venv-name
           channels:
             - conda-forge
           dependencies:
             - python >=3.6,<3.7
             - ipykernel >=5.1
             - ipywidgets
     

   • Create the new virtual env: micromamba create -f ./new-venv-name.yaml -y

     - Replace new-venv-name with your venv name

Bonus: Fancy Terminal (Oh My Posh)

• If you want to wow coworkers with your shell scripting setup, then checkout Oh My Posh for Windows terminal app

• I like to create a dedicated Windows terminal profile to avoid having to wait an extra 3 seconds for terminal to boot and conda to activate (micromamba does activate faster than conda)

  - Example config for terminal as it was confusing my first time around:

  

  1. Open terminal settings: ctrl + ,

  2. Edit command line: pwsh -NoExit -Command "& micromamba activate new_venv_name"

  - Replace new-venv-name with your venv name

• Congrats! You now have a normal powershell prompt and a dedicated micromamba terminal