L'étant

L'étant is a short for les étant, meaning "The Beings" in French.

Provide a clear provenance map, trimming out noises for comprehension.

About

A structural code comprehension tool. letant parses source files using Tree-Sitter, extracts every scope boundary and name binding, construct a queryable definition graph, provide provenance map of given position.

A Different Question

Every other tool in this space asks "where is this symbol and who uses it?" — a cartographic question that requires mapping everything. L'étant asks "where did this come from?" — a genealogical question that requires only following the lineage of what you're looking at.

This follows the natural direction of code comprehension. When you read code, you encounter a symbol and look up where it came from. L'étant only traces forward: from usage to origin.

Architecture

Data Model

All output is two types:

• Node — a code entity with a path segments, hashed to a compact NodeId inside the graph. A kind classifies the entity, a type role classifies its scope behavior.
• Edge — a directed relationship between two nodes (from → to)

Node Roles

Every node has a type field with one of three values:

| type | Description | Example kind values | | ------ | ----------- | --------------------- | | "scope" | A named scope — introduces names and is itself introduced into a parent scope | function, class, method, ... | | "anonymous" | An unnamed scope — introduces names but has no binding identity of its own | iife, if, for, while, ... | | "binding" | A pure binding — is introduced into a scope, does not introduce names | variable, member, import, parameter, ... |

Responsibilities

L'étant separates concerns across three layers:

Language plugin — interprets the raw Tree-Sitter AST for a specific language. Faithfully extracts every entity the parser exposes and maps it to the common node/edge schema. Two phases:

• capture — runs tree-sitter queries against AST nodes and returns typed match results. Decides what entity to capture from the source.
• convert — transforms captures into graph nodes and edges. Decides how the entities relate, and provides opinionated result.

Core — constructs a queryable graph based on the converted result from plugin, and provides navigable interface on top of it.

Prerequisites

• Node.js 22+ — Node 22 uses prebuilt Tree-Sitter binaries. Node 24 and 25 build from source and additionally require python3, make, and g++ with C++20 support.
• pnpm — workspace manager.
• On Node 24/25, set CXXFLAGS="-std=c++20" before installing.

Usage

# Install dependencies (Node 24/25: prefix with CXXFLAGS="-std=c++20")
pnpm install

# Build core
pnpm build

# Build all packages
pnpm build:all

# Type check everything
pnpm check-types:all

# Run CLI against mock data
pnpm dev:config

# Lint
pnpm lint

# Tests
pnpm test

License

MIT