Register grammar assets

Use a compatible, user-trusted precompiled native library and two matching Tree-sitter queries. Native libraries execute code in the editor process; ABI and query validation do not sandbox that code. Rev does not download, compile or install grammars.

Place a versioned asset set

Before starting rev, place the library and UTF-8 queries in a new versioned directory, such as ~/.local/share/rev/grammars/python-0.25.0/:

python-0.25.0/
├── parser.so
├── highlights.scm
└── completions.scm

When XDG_DATA_HOME is set, use rev/grammars beneath that directory. Relative registration paths resolve there. Use regular files and keep relative paths and their symlinks within that root. Absolute file paths are also accepted.

Prepare queries using the supported external query profile. Highlights and completion queries are both required; arbitrary upstream query files may use captures or operations outside that finite profile.

Register and check

Add this complete registration to your startup config.toml:

[language.python.external]
parser = "python-0.25.0/parser.so"
symbol = "tree_sitter_python"
highlights = "python-0.25.0/highlights.scm"
completions = "python-0.25.0/completions.scm"

Use the exported symbol and paths belonging to your actual assets. Restart rev and open a .py file, whose existing language association selects python. First use admits the library and both queries on a temporary worker. Successful admission shows External in the language status. Try M-x completion-at-point beside a declaration observed by your query.

An invalid library, ABI, symbol or query preserves bundled syntax when available; an unbundled identity remains editable as Text. A completed failure is cached for that session. Correct the assets or registration and restart to retry.

For an upgrade, install another versioned directory, change all relevant paths and restart. Never overwrite a library mapped by a running editor. Loaded native mappings remain for the process lifetime. See External grammar assets for path/query limits, fallback and replacement details.