uv plugin doesn't cache wheels to LXC host
Metadata
Current evaluation
uv plugin fails to cache wheels built from source to the LXC host's charmcraft cache, leaving the untriaged issue open and awaiting a fix.
Suggested action: needs triage
Reason: The issue lacks maintainer labels, comments, or assignees, indicating it has not yet been assessed. Per guidelines, untriaged issues require initial review to determine current relevance and priority before any other action is taken.
Staleness:
65
Complexity:
45
Confidence:
80
Support Request:
0
Issue body
### Bug Description
When the uv plugin is used with
```toml
# pyproject.toml
[tool.uv]
no-binary = true
```
wheels built from source are not saved to charmcraft's cache on the LXC host
### To Reproduce
```shell
git clone https://github.com/carlcsaposs-canonical/bug-report-charmcraft-uv-no-cache
cd bug-report-charmcraft-uv-no-cache/
mkdir ~/foo
CRAFT_SHARED_CACHE=/home/ubuntu/foo charmcraft pack -v
```
```shell
ubuntu@juju-378fe5-stg-carlcsaposs-dev-env-46:~/bug-report-charmcraft-uv-no-cache$ ls ~/foo/
charmcraft-buildd-base-v7 charmcraft.lock
ubuntu@juju-378fe5-stg-carlcsaposs-dev-env-46:~/bug-report-charmcraft-uv-no-cache$ ls ~/foo/charmcraft-buildd-base-v7/
BuilddBaseAlias.NOBLE
ubuntu@juju-378fe5-stg-carlcsaposs-dev-env-46:~/bug-report-charmcraft-uv-no-cache$ ls ~/foo/charmcraft-buildd-base-v7/BuilddBaseAlias.NOBLE/
pip
ubuntu@juju-378fe5-stg-carlcsaposs-dev-env-46:~/bug-report-charmcraft-uv-no-cache$ ls ~/foo/charmcraft-buildd-base-v7/BuilddBaseAlias.NOBLE/pip/
ubuntu@juju-378fe5-stg-carlcsaposs-dev-env-46:~/bug-report-charmcraft-uv-no-cache$
```
### Environment
Ubuntu 24.04
Using charmcraft with lxc containers
### charmcraft.yaml
```yaml
type: charm
platforms:
ubuntu@24.04:amd64:
parts:
charm-uv:
plugin: uv
source: .
build-snaps:
- astral-uv
```
### Relevant log output
```shell
N/A
```
Evaluation history
| Date | Model | Scores | Action | Summary |
|---|---|---|---|---|
| 2026-06-15 13:46:14.888418+00:00 | qwen3.6-35b-a3b-mtp-q6 |
Staleness:
65
Complexity:
45
Confidence:
80
Support Request:
0
|
needs triage | uv plugin fails to cache wheels built from source to the LXC host's charmcraft cache, leaving the untriaged issue open and awaiting a fix. |
| 2026-06-15 13:43:55.152207+00:00 | pending | — | — | — |