# Third-party dependencies

## yyjson

The salvage metadata backend uses yyjson for JSON read/write support when the
vendored source tree is available at `third_party/yyjson`.

Recommended setup:

```sh
git submodule add -b master https://github.com/ibireme/yyjson.git third_party/yyjson
git submodule update --init --recursive third_party/yyjson
```

CMake auto-detects `third_party/yyjson/CMakeLists.txt`.  When the submodule is
missing, mars_nwe still builds, but the salvage JSON entry read/write helpers
return `ENOSYS` and the yyjson-backed smoke assertions are skipped.