Add `UV_LINK_MODE=copy`

Metadata

Project: craft-parts
Number: #1451
Type: pull request
State: closed
Author: carlcsaposs-canonical
Labels: —
Created: 2026-02-09 11:21 AM UTC
Updated: 2026-02-09 11:24 AM UTC
Closed: 2026-02-09 11:23 AM UTC

Current evaluation

PR #1451 (Add `UV_LINK_MODE=copy`) was closed unmerged and replaced by canonical/craft-parts#1452, opened by the author to fix the PR title per the Conventional Commits policy check that was failing here.

Resolution: closed superseded

Reason: The one comment on the PR (carlcsaposs-canonical, 2026-02-09) states it was "Reopened as #1452 to edit pr title to include conventional commit prefix". The 'policy / Check PR title for Conventional Commits' check was failing on #1451, and canonical/craft-parts#1452 carries the same one-line change forward and is still open/approved.

Evaluated by: mr-cal-bot

No scores available.

Issue body

Companion to https://github.com/canonical/craft-providers/pull/900 When the cache dir is mounted from the LXD host, hardlinking from the global cache (uv's default behavior) is not possible e.g. ``` :: warning: Failed to hardlink files; falling back to full copy. This may lead to degraded performance. :: If the cache and target directories are on different filesystems, hardlinking may not be supported. :: If this is intentional, set `export UV_LINK_MODE=copy` or use `--link-mode=copy` to suppress this warning. ```

Evaluation history

Date	Model	Scores	Action	Summary
2026-10-03 10:09 AM UTC	stealth/space-bunny-alpha	—	closed superseded	PR #1451 (Add `UV_LINK_MODE=copy`) was closed unmerged and replaced by canonical/craft-parts#1452, opened by the author to fix the PR title per the Conventional Commits policy check that was failing here.
2026-09-25 06:17 AM UTC	stealth/space-bunny-alpha	—	closed superseded	Closed unmerged and superseded by canonical/craft-parts#1452, which carries forward the UV_LINK_MODE=copy change with a Conventional Commits-compliant title.
2026-09-25 06:17 AM UTC	stealth/space-bunny-alpha	—	closed superseded	Closed unmerged and superseded by canonical/craft-parts#1452 to fix the failed title-policy check. The replacement remained open, so UV_LINK_MODE=copy was not yet merged.
2026-07-22 02:05 PM UTC	qwen/qwen3.6-35b-a3b	—	—	Added UV_LINK_MODE=copy to resolve LXD cache hardlinking warnings. Closed and abandoned by the author, superseded by PR #1452 to correct the title format for conventional commits.
2026-07-02 07:24 AM UTC	qwen3.6-35b-a3b-mtp-q6	—	—	Superseded by PR #1452 for title formatting. Introduces UV_LINK_MODE=copy to resolve hardlinking warnings when the cache directory is mounted from an LXD host.

Update history

No update history recorded yet.

Related work

Superseded By: canonical/craft-parts#1452 (confidence 95%)
Same change re-opened as 'feat: Add `UV_LINK_MODE=copy`' to satisfy the Conventional Commits title policy; now open with approvals.
Related To: canonical/craft-providers#900 (confidence 70%)
Companion PR in craft-providers applying the same UV_LINK_MODE=copy setting; no UV_LINK_MODE references found in craft-parts source at the pinned baseline, so the change is not yet merged here.

Related issues

Issue	Project	State	Summary	Similarity
#1452 feat: Add `UV_LINK_MODE=copy`	craft-parts	open	Adds UV_LINK_MODE=copy to the uv plugin build environment to fix hardlink failures when the cache dir is LXD-mounted; companion to craft-providers#900. Approved by 4 reviewers, 1 unresolved comment, some slow CI tests failing.	75%