# MaskRay/ccls

C/C++/ObjC language server supporting cross references, hierarchies, completion and semantic highlighting

Repository: https://github.com/MaskRay/ccls
Canonical: https://ross.abutalabs.com/products/ccls
Language: C++
License: Apache-2.0
License Family: permissive
Topics: cpp, language-server-protocol, ide, lsp-server
Last push: 2026-07-02T07:04:21+00:00

## Health v2 (maintenance only)
Score: 76/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 90, release rhythm 45, longevity 100
- inputs: {"age_days": 3077, "days_push": 62, "days_rel": 291, "gap_med": 40, "n_releases_24m": 4}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 4083, forks 279 (observed 2026-08-28T04:08:34.459816+00:00)

## What it is
ccls is a C/C++/Objective-C language server implementing the Language Server Protocol, originating from cquery. It provides code completion, cross references, call/inheritance/member hierarchies, semantic highlighting, and whole-project indexing for editor integration.

## Use cases
- set up C++ code completion and go-to-definition in my editor
- find all references and callers of a C++ function
- view class inheritance hierarchies in C++ code
- get semantic syntax highlighting for C/C++ in vim or emacs
- rename symbols across a large C++ codebase
- index a large C/C++ project for fast code navigation

## When to choose
- you need deep cross-reference and hierarchy features for C/C++/Objective-C
- you want a language server with a global index of the whole codebase
- you use an editor like Vim, Emacs, or Neovim without a full IDE

## When to avoid
- you prefer clangd, which is more actively maintained and standard
- you work mainly in languages other than C/C++/Objective-C
- memory-constrained environments indexing very large projects

## Facets
- artifact type: application
- maturity: active
- function: editor, search-engine, parser
- domain: developer-tools, text-editors, programming-languages
- platform: windows, cross-platform, editor-plugin
- tags: language-server-protocol, lsp-server, c-cpp, objective-c, code-indexing, clang, code-navigation, semantic-highlighting, linux, macos

## Member repositories
- MaskRay/ccls (main) score 76

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:08:34.459816+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 2026-08-29T18:23:24.566207+00:00, confidence not recorded.
  - readme: https://github.com/MaskRay/ccls (fetched 2026-08-28T04:08:34.459816+00:00, sha c300faf8bfc9)
- Data as of 2026-08-30T08:39:29.467469+00:00.