perf(shell): pixi shell is slow with fish #4846
Description
Checks
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I have checked that this issue has not already been reported.
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I have confirmed this bug exists on the latest version of pixi, using
pixi --version.
Reproducible example
pixi info output:
System
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Pixi version: 0.58.0
Platform: osx-arm64
Virtual packages: __unix=0=0
: __osx=15.6.1=0
: __archspec=1=m2
Cache dir: /Users/user/Library/Caches/rattler/cache
Auth storage: /Users/user/.rattler/credentials.json
Config locations: /Users/user/.pixi/config.toml
Global
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Bin dir: /Users/user/.pixi/bin
Environment dir: /Users/user/.pixi/envs
Manifest dir: /Users/user/.pixi/manifests/pixi-global.toml
Workspace
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Name: new
Version: 0.1.0
Manifest file: /Users/user/Downloads/new/pixi.toml
Last updated: 28-10-2025 17:24:03
Environments
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Environment: default
Features: default
Channels: conda-forge
Dependency count: 0
Target platforms: osx-arm64
Prefix location: /Users/user/Downloads/new/.pixi/envs/default
Issue description
When using fish (with an empty config), pixi shell takes a few seconds to spawn into a shell. By contrast, starting in zsh or bash the shell launches almost instantaneously.
Running pixi shell -vvv, allow debug commands print nearly immediately, with the last command being:
DEBUG pixi_cli::shell: Starting shell 'fish ' with source command: ' source "/var/folders/gq/kk0fb78d50vdr2kh_vjdml2syy_81s/T/pixi_env_2lP.fish"'
which hangs until the shell spawns.
Expected behavior
It should start quickly, comparably with zsh or bash. Is there a setting that might ameliorate this? I've been using pixi with fish for a while now, and I believe it used to be faster in the past.