pip install julialang && julialang install && julia

Contents

• Why julialang?
• Quick start
• Everyday use
  • Install Julia · Run Julia · See what you have · Switch version · Upgrade and downgrade · Remove versions · Remove everything
• Version specs
• Command reference
• Environment variables
• How it works
• For maintainers
• Notes

Why julialang?

On machines where you have no sudo/admin rights, or where the network only reaches PyPI and GitHub (a locked-down server, a CI runner, the sandbox of Claude chat), you cannot run an installer, apt or juliaup, and julialang.org is blocked. pip install julialang fixes that: it needs nothing but pip, installs Julia in your home directory from GitHub, and works the same on Linux, macOS and Windows. As far as we know there is no other simple way to get Julia there.

Like ziglang does for Zig, julialang makes Julia installable from Python tooling. What you get:

• Tiny wheel. pip install julialang downloads a pure-Python wheel of a few KB (py3-none-any), the same on every platform.
• No julialang.org needed. The official binaries are mirrored on GitHub by CI; julialang downloads from there and verifies sha256 and md5.
• Many versions side by side. Install as many as you like, switch with one command, upgrade, downgrade, remove.
• pip-style version specs. julialang install ">=1.10,<1.13", julialang install 1.12, julialang install ~=1.12.2.
• Every stable release. The mirror covers all stable Julia versions, from 0.x to the latest.
• Zero dependencies. Standard library only. Works on Linux (x86_64, aarch64, i686), macOS (x86_64, arm64) and Windows (x86_64, i686) with Python 3.9+.

Quick start

pip install julialang
julialang install                 # latest Julia, becomes the default
julia -e 'println("hello from Julia ", VERSION)'

Julia itself is not inside the wheel: julialang install downloads it into ~/.julialang.

Everyday use

Install Julia

julialang install                 # the latest version
julialang install 1.12            # the newest 1.12.x
julialang install 1.10.5          # exactly this version
julialang install ">=1.10,<1.13"  # the newest version that satisfies the spec
julialang install 1.10 1.12       # several at once

install only adds versions: nothing is removed, and the installed version becomes the default. Pass --no-default to keep the current default:

julialang install 1.10 --no-default

Run Julia

julia is a thin shim that runs the selected Julia with your arguments. When only Python is on your PATH, julialang run does the same (everything after run goes to Julia):

julia                             # REPL
julia script.jl                   # run a script
julia -e 'print(VERSION)'
JULIALANG_VERSION=1.10 julia -e 'print(VERSION)'   # one command with another installed version
julialang run script.jl           # the same as `julia script.jl`
python -m julialang run -e 'print(VERSION)'

Which Julia runs: JULIALANG_VERSION (a spec, must be installed), else the default chosen by julialang, else the newest installed one. The shim never touches the network. If nothing is installed yet it tells you to run julialang install (set JULIALANG_AUTO_INSTALL=1 to let julia install the latest on first use instead).

See what you have

julialang                         # status: installed versions, the default, the latest on the mirror
julialang list                    # installed versions and the ones the mirror offers
julialang list --installed        # only what is on your machine
julialang list --all              # everything the mirror has
julialang latest                  # newest version on the mirror
julialang which                   # path of the executable `julia` runs
julialang fetch                   # refresh the cached list of mirrored versions now

Switch version

Switch the default among the versions you have installed:

julialang use 1.10
julia -e 'print(VERSION)'         # 1.10.x
julialang use latest

use never downloads: if the version is not installed it tells you to julialang install it first.

Upgrade and downgrade

install keeps old versions; upgrade and downgrade replace the current default:

julialang upgrade                 # install the latest, make it the default, remove the previous default
julialang upgrade 1.12            # ... or the newest 1.12.x
julialang downgrade 1.10          # same, towards an older version (the spec is required)

The previous default is deleted only after the new version is downloaded and its checksum verified. Asking upgrade for an older version (or downgrade for a newer one) is an error that points you to the other command; asking for the version you already use just says so.

Remove versions

julialang uninstall 1.12.2        # one version
julialang uninstall 1.10 1.11     # several
julialang uninstall "<1.12" --yes # a spec that matches many versions asks first; --yes skips the question

Uninstalling the default promotes the newest remaining version to be the new default.

Remove everything

julialang purge                   # delete every installed Julia and julialang's data; the pip package stays
julialang self-uninstall          # purge, then `pip uninstall julialang`

Both ask first (--yes skips the question). purge deletes every installed Julia and julialang's own files in ~/.julialang; self-uninstall does the same and then runs python -m pip uninstall -y julialang for you. (A directory set with JULIALANG_HOME is only removed if nothing else lives in it.)

Installed versions live outside your virtual environment, so a plain pip uninstall julialang leaves them in place: run julialang self-uninstall instead, or delete ~/.julialang (Windows: %USERPROFILE%\.julialang) by hand afterwards.

Version specs

Specs work like pip's, with npm-style handling of partial versions:

Quote specs that contain < or > so the shell does not treat them as redirection. Several words are joined with commas, so julialang install ">=1.10" "<1.13" means the same as julialang install ">=1.10,<1.13".

Command reference

The cached version list is trusted for one hour by status, list and latest; install, upgrade, downgrade and fetch always try the network first and fall back to the cache when offline.

Environment variables

State layout: ~/.julialang/versions/<version>/ holds each Julia, and ~/.julialang/config.json records the default and the installed versions; it is re-synchronised with the folders on every command, so you can also delete a folder by hand.

Notes

• Julia is MIT-licensed, but its binary distribution bundles third-party libraries under their own licenses (see share/julia/ and share/licenses inside each version). The code in this repository is MIT.
• The julia command of this package may shadow another julia earlier on your PATH; julialang which shows what is actually run.
• GitHub pauses scheduled workflows after 60 days without repository activity; if the weekly sync stops, re-enable it in the Actions tab.