PKG001-invalid-pyproject — Malformed pyproject.toml

Dimension: Packaging Default severity: High Languages: All (project-level) Last reviewed: 2026-05-08

What it detects

Emits when pyproject.toml exists in the project root but cannot be parsed as valid TOML. The finding is anchored to the line and column of the first parse error.

Why it matters

A broken pyproject.toml silently disables every tool that reads it: build backends (pip, build), linters (ruff, mypy), and package managers (poetry, uv). Downstream consumers who run pip install . will receive a cryptic error with no clear cause.

Configuration

No configuration knobs in v1.

Example — flagged

# pyproject.toml — truncated table header (missing closing bracket)
[project
name = "my-package"

Example — not flagged

[project]
name = "my-package"
version = "1.0.0"

Fix guidance

• Validate with taplo lint pyproject.toml or an online TOML validator.
• Common causes: unclosed [table, missing quotes around values, trailing commas in inline arrays/tables.

Suppression

Because pyproject.toml is not parsed as a Python source file by zuit, engine-level # zuit: ignore PKG001 suppression in the TOML file does not apply. Fix the TOML syntax error instead.

Implementation

Source: crates/zuit-lang-python/src/analyzers/pkg/pkg001_invalid_pyproject.rs

References

• pyproject.toml specification
• TOML specification