pipx/ansible breaks with brace version syntax

[agriffis]

good	bad
[tools] pipx = "latest" ansible = "latest"	[tools] pipx = "latest" ansible = { version = "latest" }

With the good config:

▶ mise i -f ansible
creating virtual environment...
creating shared libraries...
upgrading shared libraries...
installing ansible from spec 'ansible==13.3.0'...
done! ✨ 🌟 ✨
ansible@13.3.0                   - ansible-vault                                                                                                                                           ✔

With the bad config:

▶ mise i -f ansible
Resolved 10 packages in 158ms
Installed 10 packages in 340ms
 + ansible==13.3.0
 + ansible-core==2.20.2
 + cffi==2.0.0
 + cryptography==46.0.4
 + jinja2==3.1.6
 + markupsafe==3.0.3
 + packaging==26.0
 + pycparser==3.0
 + pyyaml==6.0.3
 + resolvelib==1.2.1
Installed 1 executable: ansible-community
ansible@13.3.0               uv tool install ansible==13.3.0                                                                                                                               ✔

It appears that with the good config, mise is using pipx without uv, and that is working.

With the right-side config, mise tries to use uv (because it's installed on my system, separately from mise) but the result doesn't work. I have no idea why this would be triggered by the different syntax.

Reproducer with simple script at https://github.com/agriffis/mise-ansible-demo

Tested this morning, this problem still exists in 2026.2.6

---

mise doctor output (it's the same with both configs above)

version: 2026.2.5 linux-x64 (2026-02-06)
activated: yes
shims_on_path: no
self_update_available: no

self_update_instructions:
  To update mise from the RPM repository, run:

    sudo dnf upgrade mise

build_info:
  Target: x86_64-unknown-linux-gnu
  Features: OPENSSL, RUSTLS_NATIVE_ROOTS, SELF_UPDATE
  Built: Fri, 6 Feb 2026 10:27:33 +0000
  Rust Version: rustc 1.93.0 (254b59607 2026-01-19)
  Profile: release

shell:
  /usr/bin/bash
  GNU bash, version 5.3.0(1)-release (x86_64-redhat-linux-gnu)
  Copyright (C) 2025 Free Software Foundation, Inc.
  License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

  This is free software; you are free to change and redistribute it.
  There is NO WARRANTY, to the extent permitted by law.

aqua:
  baked in registry tools: 2210

dirs:
  cache: ~/.cache/mise
  config: ~/.config/mise
  data: ~/.local/share/mise
  shims: ~/.local/share/mise/shims
  state: ~/.local/state/mise

config_files:
  ~/.config/mise/config.toml
  ~/src/mise-ansible-demo/b/mise.toml

ignored_config_files: (none)

backends:
  aqua
  asdf
  cargo
  conda
  core
  dotnet
  forgejo
  gem
  github
  gitlab
  go
  npm
  pipx
  spm
  http
  s3
  ubi
  vfox

plugins:
  ant                           https://github.com/mise-plugins/mise-ant.git#12b17eb
  asdf-mise-plugins-mise-maven  https://github.com/mise-plugins/mise-maven.git#456e724
  mise-plugins/mise-maven
  babashka                      https://github.com/pitch-io/asdf-babashka.git#3c26394
  clojure                       https://github.com/mise-plugins/mise-clojure.git#790f4f9
  cmake                         https://github.com/mise-plugins/mise-cmake.git#9959904
  pnpm                          https://github.com/jonathanmorley/asdf-pnpm.git#184f8cb
  yarn                          https://github.com/mise-plugins/asdf-yarn.git#74ea3b9
  zprint                        https://github.com/carlduevel/asdf-zprint.git#01c9fa5

toolset:
  aqua:BurntSushi/ripgrep@15.1.0
  aqua:anthropics/claude-code@2.0.50
  aqua:antonmedv/fx@39.2.0
  aqua:jdx/usage@2.9.0
  aqua:junegunn/fzf@0.67.0
  aqua:pypa/pipx@1.8.0
  aqua:zellij-org/zellij@0.43.1
  asdf:babashka@1.4.192
  asdf:clojure@1.12.0.1530
  asdf:cmake@4.2.0
  cargo:atuin@18.10.0
  cargo:serie@0.5.4
  cargo:stylua@2.3.1
  core:java@24.0.1
  core:node@24.11.1
  core:python@3.14.3
  core:rust@1.91.1
  github:cli/cli@2.83.2
  github:simulot/immich-go@0.31.0
  npm:@bitwarden/cli@2025.11.0
  npm:@github/copilot@0.0.362
  npm:@vscode/vsce@3.7.0
  pipx:ansible[uvx=false,pipx_args=--include-deps]@13.3.0
  ubi:borkdude/jet@0.7.27

path:
  ~/.local/share/mise/installs/python/3.14.3/bin
  ~/.local/share/mise/installs/ansible/13.3.0/bin
  ~/.local/share/mise/installs/pipx/1.8.0
  ~/.local/share/mise/installs/babashka/1.4.192/bin
  ~/.local/share/mise/installs/claude/2.0.50/bin
  ~/.local/share/mise/installs/clojure/1.12.0.1530/bin
  ~/.local/share/mise/installs/cmake/4.2.0/bin
  ~/.local/share/mise/installs/fx/39.2.0
  ~/.local/share/mise/installs/node/24.11.1/bin
  ~/.cargo/bin
  ~/.local/share/mise/installs/zellij/0.43.1
  ~/.local/share/mise/installs/cargo-atuin/18.10.0/bin
  ~/.local/share/mise/installs/cargo-serie/0.5.4/bin
  ~/.local/share/mise/installs/cargo-stylua/2.3.1/bin
  ~/.local/share/mise/installs/npm-bitwarden-cli/2025.11.0/bin
  ~/.local/share/mise/installs/npm-github-copilot/0.0.362/bin
  ~/.local/share/mise/installs/npm-vscode-vsce/3.7.0/bin
  ~/.local/share/mise/installs/ubi-borkdude-jet/0.7.27
  ~/.local/share/mise/installs/usage/2.9.0
  ~/.local/share/mise/installs/github-simulot-immich-go/0.31.0
  ~/.local/share/mise/installs/fzf/0.67.0
  ~/.local/share/mise/installs/ripgrep/15.1.0/ripgrep-15.1.0-x86_64-unknown-linux-musl
  ~/.local/share/mise/installs/github-cli-cli/2.83.2/bin
  ~/.local/share/mise/installs/java/24.0.1/bin
  ~/bin
  ~/.local/bin
  ~/.bun/bin
  ~/.cask/bin
  ~/.gem/bin
  ~/.go/bin
  ~/.npm-local/bin
  ~/.yarn/bin
  /usr/lib64/ccache/bin
  /usr/lib/ccache/bin
  /usr/lib64/ccache
  /usr/lib/ccache
  /usr/local/bin
  /usr/local/sbin
  /usr/bin
  /usr/sbin
  ~/.composer/vendor/bin
  /bin
  /sbin
  /var/lib/flatpak/exports/bin

env_vars:
  MISE_NODE_COREPACK=true
  MISE_SHELL=bash

settings:
  experimental                         true     ~/.config/mise/config.toml
  idiomatic_version_file_enable_tools  ["node"] ~/.config/mise/config.toml

1 warning found:

1. tool 'claude' installed with explicit backend 'npm:@anthropic-ai/claude-code'
   differs from registry recommendation 'aqua:anthropics/claude-code'.
   To switch: mise uninstall --all claude && mise install claude

No problems found

[agriffis]

I added this to the pipx backend:

▶ git di
diff --git a/src/backend/pipx.rs b/src/backend/pipx.rs
index 89b488b29..d61fa4de2 100644
--- a/src/backend/pipx.rs
+++ b/src/backend/pipx.rs
@@ -199,6 +199,8 @@ impl Backend for PIPXBackend {
             && Settings::get().pipx.uvx != Some(false)
             && tv.request.options().get("uvx") != Some(&"false".to_string());

+        debug!("use_uvx = {}", use_uvx);
+
         if !use_uvx {
             self.warn_if_dependency_missing(
                 &ctx.config,

and this showed that the good config does:

DEBUG 30 [src/backend/pipx.rs:202] use_uvx = false

while the bad config does:

DEBUG 31 [src/backend/pipx.rs:202] use_uvx = true

This seems like a bug. I don't know why the different version syntaxes would intentionally have this result.

I haven't done much in rust, but it seems like the difference is happening here:

mise/src/backend/pipx.rs

Lines 197 to 200 in 3439a73

	// Check if pipx is available (unless uvx is being used)
	let use_uvx = self.uv_is_installed(&ctx.config).await
	&& Settings::get().pipx.uvx != Some(false)
	&& tv.request.options().get("uvx") != Some(&"false".to_string());

My guess is that tv.request.options().get("uvx") resolves to something different in the two scenarios...

Yup, a little more debugging shows:

good

DEBUG 29 [src/backend/pipx.rs:197] tv.request.options(): ToolVersionOptions { os: None, install_env: {}, opts: {"uvx": "false", "pipx_args": "--include-deps"} }

bad

DEBUG 28 [src/backend/pipx.rs:197] tv.request.options(): ToolVersionOptions { os: None, install_env: {}, opts: {} }

The problem is that this line isn't applying properly in the "bad" case:

mise/registry/ansible.toml

Line 1 in 3439a73

backends = ["pipx:ansible[uvx=false,pipx_args=--include-deps]"]

so the workaround is to apply them in the config:

[tools]
ansible = { version = "latest", uvx = false, pipx_args = "--include-deps" }
pipx = "latest"

[risu729]

I created a PR to remove that syntax from the registry. This is not a proper fix but at least prevents the issue. #8146
Nvm, I noticed #8044 fixed this problem.

[agriffis]

Thank you! I checked and you're right, #8044 fixes this.