Mojo🔥 Installation on Ubuntu 23.04 [Not Stable]

Warning: Not Stable, please DO NOT try it on production environment

The default Python3 version for Ubuntu 23.04 is 3.11, thus we must install version from 3.8 to 3.10 for Mojo🔥 requirement.

Photo by WrongTog on Unsplash

Installation Guide

Sign in to https://developer.modular.com/signup?redirect=%2Fdownload to get the MODULAR_AUTH_TOKEN

Install modular CLI

$ curl https://get.modular.com | \
  MODULAR_AUTH=<MODULAR_AUTH_TOKEN> \
  sh -

Install mojo SDK via modular command

$ modular install mojo

Output from Ubuntu 23.04 with Python3.11

$ modular install mojo
# Found release for https://packages.modular.com/mojo @ 0.2.1, installing to /home/user/.modular/pkg/packages.modular.com_mojo
# Downloads complete, setting configs...
# Configs complete, running post-install hooks...
error: externally-managed-environment

× This environment is externally managed
╰─> To install Python packages system-wide, try apt install
    python3-xyz, where xyz is the package you are trying to
    install.
    
    If you wish to install a non-Debian-packaged Python package,
    create a virtual environment using python3 -m venv path/to/venv.
    Then use path/to/venv/bin/python and path/to/venv/bin/pip. Make
    sure you have python3-full installed.
    
    If you wish to install a non-Debian packaged Python application,
    it may be easiest to use pipx install xyz, which will manage a
    virtual environment for you. Make sure you have pipx installed.
    
    See /usr/share/doc/python3.11/README.venv for more information.

note: If you believe this is a mistake, please contact your Python installation or OS distribution provider. You can override this, at the risk of breaking your Python installation or OS, by passing --break-system-packages.
hint: See PEP 668 for the detailed specification.
modular: error: failed to run python:

Build Python3.10 from Source Code [ref1] [ref2]

$ sudo apt install -y wget build-essential libreadline-dev libncursesw5-dev libssl-dev libsqlite3-dev tk-dev libgdbm-dev libc6-dev libbz2-dev libffi-dev zlib1g-dev

$ wget -c https://www.python.org/ftp/python/3.10.13/Python-3.10.13.tar.xz
$ tar -Jxf Python-3.10.13.tar.xz

$ cd Python-3.10.13/
$ ./configure --enable-optimizations --enable-shared
$ sudo make -j4 && sudo make altinstall

The python3.10 will be installed in /usr/local/bin/

$ which python3.10
/usr/local/bin/python3.10

$ which python3
/usr/bin/python3


$ python3 --version
Python 3.11.4

Config Python3 version with update-alternatives command to make python3.10 as system python3 temporary. [ref]

$ sudo update-alternatives --list python3
update-alternatives: error: no alternatives for python3

$ sudo update-alternatives --list python
update-alternatives: error: no alternatives for python

$ sudo update-alternatives --install /usr/bin/python3 python3 /usr/local/bin/python3.10 1
$ sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.11 1

$ sudo update-alternatives --config python3
There are 2 choices for the alternative python3 (providing /usr/bin/python3).

  Selection    Path                       Priority   Status
------------------------------------------------------------
* 0            /usr/local/bin/python3.10   2         auto mode
  1            /usr/bin/python3.11         1         manual mode
  2            /usr/local/bin/python3.10   2         manual mode

Press <enter> to keep the current choice[*], or type selection number:

After config the python3 version for the system, please aware to check again.

$ python3 --version
Python 3.10.13

Finally, time to install mojo again.

$ modular install mojo

After Installed, add modular path for system environment

## Bash
echo 'export MODULAR_HOME="$HOME/.modular"' >> ~/.bashrc
echo 'export PATH="$HOME/.modular/pkg/packages.modular.com_mojo/bin:$PATH"' >> ~/.bashrc
source ~/.bashrc

## ZSH
echo 'export MODULAR_HOME="$HOME/.modular"' >> ~/.zshrc
echo 'export PATH="$HOME/.modular/pkg/packages.modular.com_mojo/bin:$PATH"' >> ~/.zshrc
source ~/.zshrc

Ready to go

$ mojo

Error & Fix

modular: error: failure detected

modular: error: failure detected - please run `modular clean` and try again
==========================
Failure Information:
 - Creating symlink for /home/user/.modular/pkg/packages.modular.com_mojo/lib/liblldb.so.18.0.0git -> /home/user/.modular/pkg/packages.modular.com_mojo/lib/liblldb.so failed: File exists
 - Creating symlink for /home/user/.modular/pkg/packages.modular.com_mojo/lib/libMojoJupyter.so.18git -> /home/user/.modular/pkg/packages.modular.com_mojo/lib/libMojoJupyter.so failed: File exists
 - Creating symlink for /home/user/.modular/pkg/packages.modular.com_mojo/lib/liblldb.so.18.0.0git -> /home/user/.modular/pkg/packages.modular.com_mojo/lib/liblldb.so.18git failed: File exists
 - Creating symlink for /home/user/.modular/pkg/packages.modular.com_mojo/lib/libKGENCompilerRTShared.so.18git -> /home/user/.modular/pkg/packages.modular.com_mojo/lib/libKGENCompilerRTShared.so failed: File exists
 - Creating symlink for /home/user/.modular/pkg/packages.modular.com_mojo/lib/libMojoLLDB.so.18git -> /home/user/.modular/pkg/packages.modular.com_mojo/lib/libMojoLLDB.so failed: File exists
 - Creating symlink for /home/user/.modular/pkg/packages.modular.com_mojo/lib/libLLCLRuntimeGlobals.so.18git -> /home/user/.modular/pkg/packages.modular.com_mojo/lib/libLLCLRuntimeGlobals.so failed: File exists
 - Creating symlink for /home/user/.modular/pkg/packages.modular.com_mojo/lib/libMSupportGlobals.so.18git -> /home/user/.modular/pkg/packages.modular.com_mojo/lib/libMSupportGlobals.so failed: File exists
==========================

$ module clean && modular install mojo

python3: error while loading shared libraries: libpython3.10.so.1.0: cannot open shared object file: No such file or directory

$ find /usr/local/lib/ -name "libpython*.so*"
/usr/local/lib/libpython3.10.so.1.0
/usr/local/lib/libpython3.so
/usr/local/lib/libpython3.10.so

$ export LD_LIBRARY_PATH="/usr/local/lib/:$LD_LIBRARY_PATH"
$ module clean && modular install mojo

Thanks for your time, hope this article can help you install mojo in Ubuntu 23.04.