TOtome·Jan 31, 2025
They also have Glean: https://github.com/facebookincubator/Glean
In A better build system for OCamlfacebookincubator
Glean
Hack2021–2025
facebookincubator / Glean
Glean
System for collecting, deriving and working with facts about source code.
4Distinct people
5Mentions
1Explicit recommenders
1.4KGitHub stars
What to know before exploring
What it is
System for collecting, deriving and working with facts about source code.
GitHub
Where it is used
No documented product use has been verified yet.
What people are saying
Cool! I would love to play around with this. How do I write a schema and indexer for my favorite programming language that isn't currently (and won't be) supported with…
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This week on Hacker News
Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 3:56:07 PM UTC.
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Mentions over time
HN mentions by year5 dated mentions
Observed mentions: 2021-08-31 11:29:28 UTC to 2025-01-31 13:21:39 UTC.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| 2021 | 2021-01-01 00:00:00 UTC | 2022-01-01 00:00:00 UTC | 3 | 0 | 3 |
| 2022 | 2022-01-01 00:00:00 UTC | 2023-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2023 | 2023-01-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2024 | 2024-01-01 00:00:00 UTC | 2025-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2025 | 2025-01-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 2 | 0 | 2 |
What Hacker News says
5 sourcesI'm a little bit confused is it the opensource that searches also in jira, wiki, slack, ..? https://github.com/facebookincubator/glean ?
In Indexing Code at Scale with GleanKythe has one schema, whereas with Glean each language has its own schema with arbitrary amounts of language-specific detail. You can get a language-agnostic view by defining an abstraction layer as a schema. Our current (work in progress) language-agnostic layer is called "codemarkup" https://github.com/facebookincubator/Glean/blob/main/glean/s...
For wiring up the indexer, there are various methods, it tends to depend very much on the language and the build system. For Flow for example, Glean output is just built into the typechecker, you just run it with some flags to spit out the Glean data. For C++, you need to get the compiler flags from the build system to pass to the Clang frontend. For Java the indexer is a compiler plugin; for Python it's built on libCST. Some indexers send their data directly to a Glean server, others generate
Read the rest
files of JSON that get sent using a separate command-line tool.
References use different methods depending on the language. For Flow for example there is a fact for an import that matches up with a fact for the export in the other file. For C++ there are facts that connect declarations with definitions, and references with declarations.
Cool! I would love to play around with this.
How do I write a schema and indexer for my favorite programming language that isn't currently (and won't be) supported with official releases?
For Schemas, [1] says to modify (or base new ones off) these: https://github.com/facebookincubator/Glean/tree/main/glean/s...
For Indexers, it's a little less clear but it looks like I need to write my own type checker?
[1] https://glean.software/docs/schema/workflow
In Glean – System for collecting, deriving and querying facts about source codeThere will be more indexers: we have Python, C++/Objective C, Rust, Java and Haskell. It's just a case of getting them ready to open source. You can see the schemas for most of these already in the repo: https://github.com/facebookincubator/Glean/tree/main/glean/s...
In Glean – System for collecting, deriving and querying facts about source code