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](https://github.com/astral-sh/uv/pull/21295))
### Enhancements

- Report cache-cleaning space savings from filesystem block allocation and avoid double-counting hard links ([#21261](https://github.com/astral-sh/uv/pull/21261))
- Limit warnings about unbounded `uv_build` requirements to source-distribution builds ([#21078](https://github.com/astral-sh/uv/pull/21078))
- Display byte counts below 1 KiB without a fractional part ([#21237](https://github.com/astral-sh/uv/pull/21237))

### Preview features

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

### Performance

- Enable profile-guided optimization for Linux x86-64 release binaries ([#21001](https://github.com/astral-sh/uv/pull/21001))
- Enable profile-guided optimization for Windows x86-64 release binaries ([#21003](https://github.com/astral-sh/uv/pull/21003))
- Enable profile-guided optimization for macOS ARM64 release binaries ([#21002](https://github.com/astral-sh/uv/pull/21002))
- Enable profile-guided optimization for Linux ARM64 release binaries ([#21004](https://github.com/astral-sh/uv/pull/21004))
- Speed up syncing projects with many activated conflict items by reusing their encoded representation ([#21148](https://github.com/astral-sh/uv/pull/21148))

### Bug fixes

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

### Other changes

- Add Python 3.15 release-candidate Docker images ([#21293](https://github.com/astral-sh/uv/pull/21293))
- Raise the minimum supported Rust version to 1.96 and update the repository toolchain to Rust 1.98 ([#21258](https://github.com/astral-sh/uv/pull/21258))

## Install uv 0.12.6

### Install prebuilt binaries via shell script

```sh
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

```sh
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

|  File  | Platform | Checksum |
|--------|----------|----------|
| [uv-aarch64-apple-darwin.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-aarch64-apple-darwin.tar.gz) | Apple Silicon macOS | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-aarch64-apple-darwin.tar.gz.sha256) |
| [uv-x86_64-apple-darwin.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-x86_64-apple-darwin.tar.gz) | Intel macOS | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-x86_64-apple-darwin.tar.gz.sha256) |
| [uv-aarch64-pc-windows-msvc.zip](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-aarch64-pc-windows-msvc.zip) | ARM64 Windows | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-aarch64-pc-windows-msvc.zip.sha256) |
| [uv-i686-pc-windows-msvc.zip](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-i686-pc-windows-msvc.zip) | x86 Windows | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-i686-pc-windows-msvc.zip.sha256) |
| [uv-x86_64-pc-windows-msvc.zip](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-x86_64-pc-windows-msvc.zip) | x64 Windows | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-x86_64-pc-windows-msvc.zip.sha256) |
| [uv-aarch64-unknown-linux-gnu.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-aarch64-unknown-linux-gnu.tar.gz) | ARM64 Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-aarch64-unknown-linux-gnu.tar.gz.sha256) |
| [uv-i686-unknown-linux-gnu.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-i686-unknown-linux-gnu.tar.gz) | x86 Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-i686-unknown-linux-gnu.tar.gz.sha256) |
| [uv-powerpc64le-unknown-linux-gnu.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-powerpc64le-unknown-linux-gnu.tar.gz) | PPC64LE Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-powerpc64le-unknown-linux-gnu.tar.gz.sha256) |
| [uv-riscv64gc-unknown-linux-gnu.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-riscv64gc-unknown-linux-gnu.tar.gz) | RISCV Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-riscv64gc-unknown-linux-gnu.tar.gz.sha256) |
| [uv-s390x-unknown-linux-gnu.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-s390x-unknown-linux-gnu.tar.gz) | S390x Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-s390x-unknown-linux-gnu.tar.gz.sha256) |
| [uv-x86_64-unknown-linux-gnu.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-x86_64-unknown-linux-gnu.tar.gz) | x64 Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-x86_64-unknown-linux-gnu.tar.gz.sha256) |
| [uv-armv7-unknown-linux-gnueabihf.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-armv7-unknown-linux-gnueabihf.tar.gz) | ARMv7 Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-armv7-unknown-linux-gnueabihf.tar.gz.sha256) |
| [uv-aarch64-unknown-linux-musl.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-aarch64-unknown-linux-musl.tar.gz) | ARM64 MUSL Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-aarch64-unknown-linux-musl.tar.gz.sha256) |
| [uv-i686-unknown-linux-musl.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-i686-unknown-linux-musl.tar.gz) | x86 MUSL Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-i686-unknown-linux-musl.tar.gz.sha256) |
| [uv-riscv64gc-unknown-linux-musl.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-riscv64gc-unknown-linux-musl.tar.gz) | RISCV MUSL Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-riscv64gc-unknown-linux-musl.tar.gz.sha256) |
| [uv-x86_64-unknown-linux-musl.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-x86_64-unknown-linux-musl.tar.gz) | x64 MUSL Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-x86_64-unknown-linux-musl.tar.gz.sha256) |
| [uv-arm-unknown-linux-musleabihf.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-arm-unknown-linux-musleabihf.tar.gz) | ARMv6 MUSL Linux (Hardfloat) | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-arm-unknown-linux-musleabihf.tar.gz.sha256) |
| [uv-armv7-unknown-linux-musleabihf.tar.gz](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-armv7-unknown-linux-musleabihf.tar.gz) | ARMv7 MUSL Linux | [checksum](https://releases.astral.sh/github/uv/releases/download/0.12.6/uv-armv7-unknown-linux-musleabihf.tar.gz.sha256) |

## 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](https://cli.github.com/manual/gh_attestation_verify):
```sh
gh attestation verify <file-path of downloaded artifact> --repo astral-sh/uv
```

You can also download the attestation from [GitHub](https://github.com/astral-sh/uv/attestations) and verify against that directly:
```sh
gh attestation verify <file-path of downloaded artifact> --bundle <file-path of downloaded attestation>
```