astral-sh/ty 0.0.84

on GitHub

Release Notes

Released on 2026-09-24.

This release addresses GHSA-vxvm-j4xq-q7m4, a use-after-free vulnerability during incremental type checking that can result in arbitrary code execution when analyzing a specially crafted Python project. Users who run ty on untrusted code should upgrade to 0.0.84 or newer.

Bug fixes

• Fix stale diagnostics from the LSP server after toggling showSyntaxErrors (#28759)

LSP server

• Complete string keys from dictionary initializers (#28820)
• Support LSP requests against closed documents (#28595)
• Select projects for external files using import search paths (#28594)
• Use workspace editor settings for external files (#28639)

Performance

• Avoid repeated subtyping checks for materialized recursive protocols (#28774)
• Skip reading notebooks when discovering scripts (#28781)

Core type checking

• Avoid incorrect simplification of TypeIs materializations (#28817)
• Fix disjointness of generic class types (#28787)
• Fix staticmethod shadowing through generic receivers and unions (#28766)
• Infer callable signatures from bounded type variables (#28599)
• Infer constant membership in inline list and set literals (e.g. "foo" in ["foo"] is now inferred as Literal[True]) (#28676)
• Infer through optional generic containers in the legacy solver (#28791)
• Preserve call narrowing during cyclic inference (#28708)
• Preserve intersections of type guard return types (#28796)
• Use subtyping for constraint-set implication (#28657)

Configuration

• Disable invalid-legacy-positional-parameter by default (#28834)

Other changes

• Only consider reachable definitions when determining whether a condition should be exempted from redundant-condition(-strict) due to the condition being defined relative to sys.version_info, sys.platform, os.name or typing.TYPE_CHECKING (#28788)

Contributors

• @ibraheemdev
• @zsol
• @charliermarsh
• @lerebear
• @MichaReiser
• @ewdurbin
• @carljm
• @sharkdp

Install ty 0.0.84

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://releases.astral.sh/github/ty/releases/download/0.0.84/ty-installer.sh | sh

Install prebuilt binaries via powershell script

powershell -ExecutionPolicy Bypass -c "irm https://releases.astral.sh/github/ty/releases/download/0.0.84/ty-installer.ps1 | iex"

Download ty 0.0.84

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 <file-path of downloaded artifact> --repo astral-sh/ty

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

gh attestation verify <file-path of downloaded artifact> --bundle <file-path of downloaded attestation>