altair-viz/altairNew scan
97/ 100 · A

A top-tier open source project. Docs, tests, and CI are all in excellent shape.

Declarative visualization library for Python

Python10,406 starsBSD-3-Clauseupdated 3d ago

Outstanding work. A score of 97/100 puts this repo in a very small tier of truly well-engineered open source projects.

DocumentationREADME, setup, examples, license
96
EngineeringTests, CI, linting, lockfiles
98
Project healthDescription, activity, stars, deps
100

What to fix first

The highest-impact improvements for this repo.

  1. 1
    CI/CD
    EngineeringInfo

    Upload coverage to Codecov, Coveralls, or report it with `--coverage` flags.

  2. 2
    Install and run instructions
    DocumentationInfo

    Add a .env.example listing all required environment variables so contributors know what to set up.

  3. 3
    Reproducibility
    EngineeringInfo

    Add a Dockerfile, .nvmrc, or .python-version to pin the runtime version and make the environment reproducible.

Detailed breakdown

Documentation

96
  • README100
    • README is present.
    • README is well structured with multiple sections.
    • README includes screenshots or visuals. Great for first impressions.
    • README has code examples.
    • README links to a live demo or deployed app.
    • README includes status badges.
  • Install and run instructions90
    • README documents how to install the project.
    • README documents how to run the project.
    • If your project uses environment variables, add a .env.example listing them (+10 pts).Add a .env.example listing all required environment variables so contributors know what to set up.
  • License100
    • Licensed under BSD-3-Clause.
  • Contributing guide91
    • Contributing guide is detailed and thorough.
    • Contributing guide lacks a setup section (−12 pts).Show new contributors how to get a local dev environment running.
    • Contributing guide describes code style expectations.
    • Contributing guide explains how to run tests.
    • Contributing guide describes the PR/review workflow.
    • Contributing guide includes code examples.
    • Code of conduct present.

Engineering

98
  • Tests100
    • Test files detected (tests).
    • Pytest is fully configured in pyproject.toml with testpaths and test files detected.
  • CI/CD100

    Not applicable?

    • CI is configured (.github/workflows/build-free-threaded.yml).
    • CI workflow runs tests.
    • CI runs on pull requests, not just on pushes to main.
    • CI workflow runs a lint or format check.
    • CI runs type checking (tsc, mypy, cargo check, etc.).
    • Optional: report test coverage in CI.Upload coverage to Codecov, Coveralls, or report it with `--coverage` flags.
    • CI tests across multiple environments or versions.
  • Linting and formatting100
    • pyproject.toml configures both a formatter/linter (ruff/black) and type checking (mypy).
  • Reproducibility90
    • Lockfile present (uv.lock). Installs are reproducible.
    • No Dockerfile or runtime version pin found. Adding one earns +10 pts.Add a Dockerfile, .nvmrc, or .python-version to pin the runtime version and make the environment reproducible.
    • Dependabot covers 2 ecosystems (github-actions, uv). Dependencies stay current.
  • Issue and PR templates90
    • Issue or PR templates present.
    • Optional: add a SECURITY.md.A SECURITY.md explains how to responsibly disclose vulnerabilities. Worth adding once the project has real users.

Project health

100
  • Dependency manifest100
    • Dependency manifest found (pyproject.toml).
    • pyproject.toml has a [project] table with package metadata.
    • pyproject.toml includes a description.
    • pyproject.toml specifies requires-python, preventing installs on incompatible versions.
    • pyproject.toml has a [build-system] table. The package can be built and published.
  • Repository metadata100
    • Repository has a description.
    • Primary language detected: Python.
    • pyproject.toml [project] metadata is complete (description, authors, urls).
  • Activity100
    • Actively maintained (pushed within the last month).
    • 10,406 stars.
  • Housekeeping100
    • .gitignore present.
Repository files20 root entries
  • .github
    Good: CI is configured (.github/workflows/build-free-threaded.yml).
    Good: Dependabot covers 2 ecosystems (github-actions, uv). Dependencies stay current.
    Good: Issue or PR templates present.
  • altair
  • design
  • doc
  • images
  • paper
  • sphinxext
  • tests
    Good: Test files detected (tests).
  • tools
  • .gitattributes
  • .gitignore
    Good: .gitignore present.
  • CODE_OF_CONDUCT.md
    Good: Code of conduct present.
  • cog.toml
  • CONTRIBUTING.md
    Good: Contributing guide is detailed and thorough.
    Info: Contributing guide lacks a setup section (−12 pts).Fix: Show new contributors how to get a local dev environment running.
    Good: Contributing guide describes code style expectations.
    Good: Contributing guide explains how to run tests.
    Good: Contributing guide describes the PR/review workflow.
    Good: Contributing guide includes code examples.
  • LICENSE
    Good: Licensed under BSD-3-Clause.
  • NOTES_FOR_MAINTAINERS.md
  • pyproject.toml
    Good: Dependency manifest found (pyproject.toml).
  • README.md
    Good: README is present.
    Good: README is well structured with multiple sections.
    Good: README includes screenshots or visuals. Great for first impressions.
    Good: README has code examples.
    Good: README links to a live demo or deployed app.
    Good: README includes status badges.
    Good: README documents how to install the project.
    Good: README documents how to run the project.
  • RELEASING.md
  • uv.lock
    Good: Lockfile present (uv.lock). Installs are reproducible.