# facebookincubator/Glean

System for collecting, deriving and working with facts about source code.

Repository: https://github.com/facebookincubator/Glean
Canonical: https://ross.abutalabs.com/products/glean
Homepage: https://glean.software/
Language: Hack
License: NOASSERTION
License Family: other
Last push: 2026-08-25T17:32:33+00:00

## Health v2 (maintenance only)
Score: 77/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 35, longevity 100
- inputs: {"age_days": 2200, "days_push": 8, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1391, forks 93 (observed 2026-08-28T04:04:35.977939+00:00)

## What it is
Glean is a system for collecting, storing, and querying facts about source code, such as symbol definitions, references, call hierarchies, and type relationships. It stores typed, schema-defined facts in a RocksDB-backed database and provides a Datalog-style query language called Angle for precise semantic code analysis at monorepo scale.

## Use cases
- find all callers of a function across a monorepo
- jump to definition and find references for code navigation tools
- build refactoring and API migration tools that locate every callsite or implementer
- power IDE features and coding agents with accurate semantic code queries
- detect dead code or write custom linters via code structure queries
- index large codebases in C++, Python, Java, Go, Rust, and TypeScript

## When to choose
- you need precise, semantic answers about code structure rather than text-based grep matching
- you are analyzing very large codebases or monorepos with billions of facts
- you want cross-file and cross-language code intelligence for IDEs, bots, or LLM coding agents
- you need a queryable database of code facts with extensible schemas

## When to avoid
- you only need simple text-based code search without semantic understanding
- your language has no indexer or LSIF/SCIP support available
- you want a lightweight tool without running a storage backend and query engine
- you need a turnkey hosted solution rather than a self-managed system

## Facets
- artifact type: service
- maturity: active
- function: search-engine, parser, database, developer-tools
- domain: developer-tools, parsers, programming-languages, apis
- platform: cli
- tags: code-indexing, code-search, static-analysis, datalog, monorepo, cross-references, angle-query-language, code-navigation, linux, macos, docker

## Member repositories
- facebookincubator/Glean (main) score 77

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:35.977939+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T04:39:36.004881+00:00, confidence not recorded.
  - readme: https://github.com/facebookincubator/Glean (fetched 2026-08-28T04:04:35.977939+00:00, sha f70dc2fc19f4)
  - homepage: https://glean.software/ (fetched 2026-08-29T11:54:36.358930+00:00, sha bf0ab1d51cdc)
  - site_page: https://glean.software/docs/introduction (fetched 2026-08-29T11:54:36.367972+00:00, sha 7e888bdbbd4c)
- Data as of 2026-08-30T08:39:29.467469+00:00.