Instagram/LibCST
A concrete syntax tree parser and serializer library for Python that preserves many aspects of Python's abstract syntax tree observed · 2026-08-28
Health v2 · maintenance only
93/100
- Activity 97
- Release rhythm 83
- Longevity 100
Flags: no_license
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-09-03. Adoption (stars, forks) is never an input.
- gap_med: 45.0
- age_days: 2584
- days_rel: 35
- days_push: 22
- n_releases_24m: 11
Adoption not part of the score
1939 stars · 228 forks observed · 2026-08-28
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded
LibCST is a concrete syntax tree (CST) parser and serializer library for Python that preserves formatting details like whitespace and comments. It enables lossless programmatic reading, analysis, and transformation of Python source code.
Use cases
- parse python source code into a syntax tree
- write codemods to refactor python codebases
- build custom linters for python
- automatically rewrite python files while preserving formatting
- analyze python code for static analysis tools
When to choose
- you need lossless round-tripping of python source including comments and whitespace
- you are building codemods, linters, or refactoring tools for python
- you need typed tree nodes with visitor and transformer patterns
When to avoid
- you only need the abstract syntax tree without formatting details (use ast)
- you are parsing languages other than python
- you need extremely fast parsing with no tree fidelity requirements
Facets
library · maturity active
parser serialization developer-tools parsers developer-tools programming-languages python cross-platform concrete-syntax-tree code-analysis codemod python-source-transformation ast
1 source
- readme: https://github.com/Instagram/LibCST · fetched 2026-08-28 · 5b9ce80c1ab9
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| Instagram/LibCST | main | 93 |
For agents
markdown · JSON · MCP: product_card(name="Instagram/LibCST")
Data as of 2026-08-30T08:39:29.467469+00:00 · Report a problem