0.12.6

Release Notes

Released on 2026-08-25.

Python

• Update CPython to use OpenSSL 3.5.8 and libffi 3.4.8 #21295)

Enhancements

• Report cache-cleaning space savings from filesystem block allocation and avoid double-counting hard links (#21261)
• Limit warnings about unbounded uv_build requirements to source-distribution builds (#21078)
• Display byte counts below 1 KiB without a fractional part (#21237)

Preview features

• Add uv workspace metadata --sync --exact to remove packages outside the selected resolution (#21117)
• Add the artifact-hash-filtering preview feature to make uv pip compile --generate-hashes honor --only-binary and --no-binary (#21235)
• Respect package-specific exclude-newer cutoffs when uv check selects its ty executable (#21227)
• Preserve virtual-environment hints from tar-codec source-distribution errors when the base interpreter is outside a bin directory (#21146)

Performance

• Enable profile-guided optimization for Linux x86-64 release binaries (#21001)
• Enable profile-guided optimization for Windows x86-64 release binaries (#21003)
• Enable profile-guided optimization for macOS ARM64 release binaries (#21002)
• Enable profile-guided optimization for Linux ARM64 release binaries (#21004)
• Speed up syncing projects with many activated conflict items by reusing their encoded representation (#21148)

Bug fixes

• Allow explicit uv build and non-editable first-party workspace packages when no-build is enabled (#21294)
• Reuse configured index credentials during uv tool upgrade when the tool receipt references the same index (#21275)
• Ensure full 40-character Git commit pins resolve to the requested object instead of a SHA-named branch (#21224)
• Prevent TLS segfaults in riscv64 musl release binaries (#21158)
• Preserve dependencies selected by recursive extras when markers mix production and extra conditions (#21181)
• Preserve version constraints from transitively referenced recursive extras (#21209)
• Resolve repository-relative Git archive dependencies inside the checkout during the initial uv sync (#21264)
• Return an error instead of panicking when a bearer token cannot be encoded as an HTTP header (#21282)
• Do not misclassify package URLs ending in .py as local script paths (#21144)
• Use directory creation times consistently across libc implementations for directory cache-keys entries (#21137)
• Promote human-readable sizes to the next unit at rounding boundaries (#21136)

Other changes

• Add Python 3.15 release-candidate Docker images (#21293)
• Raise the minimum supported Rust version to 1.96 and update the repository toolchain to Rust 1.98 (#21258)

Install uv 0.12.6

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-installer.sh | sh

Install prebuilt binaries via powershell script

powershell -ExecutionPolicy Bypass -c "irm https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-installer.ps1 | iex"

Download uv 0.12.6

Verifying GitHub Artifact Attestations

The artifacts in this release have attestations generated with GitHub Artifact Attestations. These can be verified by using the GitHub CLI:

gh attestation verify  --repo astral-sh/uv

You can also download the attestation from GitHub and verify against that directly:

gh attestation verify  --bundle