meta-ast is a fast, standalone static analysis engine that parses multi-language projects, builds symbol-level dependency graphs, detects cyclic imports, and generates MetaCall deployment manifests. Written in Rust, powered by tree-sitter, with no runtime execution of user code.
Built as part of Google Summer of Code 2026 for the MetaCall organization by Khaled Alam.
Supports 8 languages: Python, JavaScript, TypeScript, TSX, C, C++, Rust, Go.
# Requires Rust toolchain - https://rustup.rs
git clone https://github.com/metacall/meta-ast.git
cd meta-ast
cargo build --releaseThe binary is at ./target/release/meta-ast.
meta-ast is published to crates.io. With a
Rust toolchain installed, install the latest release in one command:
cargo install meta-astThis installs the core analyzer (inspect and graph subcommands). To also
enable the MetaCall deployment manifest generator (deploy subcommand), install
with the metacall-deploy feature:
cargo install meta-ast --features metacall-deployThe binary lands at ~/.cargo/bin/meta-ast (on your PATH if cargo's bin dir is
configured). No external services, network calls, or runtime execution of your
code are involved.
git clone https://github.com/metacall/meta-ast.git
cd meta-ast
cargo build --release # core only
# or, with the deploy module:
cargo build --release --features metacall-deployThe binary is at ./target/release/meta-ast.
meta-ast exists to give polyglot codebases a single, fast, language-agnostic
view of their structure without executing any user code. Its objectives:
- Parse 8 languages with one tool. Python, JavaScript, TypeScript, TSX, C, C++, Rust, and Go flow through a uniform tree-sitter pipeline. A mixed Python/JS/Rust project is one graph, not three glued together.
- Normalize to a stable IR. Every declaration becomes a
Symbolwith a consistent shape and a stable JSON/YAML output contract. Downstream tooling consumes results without caring about the source language. - Surface deployment structure. Cross-file dependency graphs plus Tarjan SCC reveal cyclic import clusters and independent units. These feed the MetaCall Function Mesh deployment model via pod-based manifests.
- Recover, never abort. Partial or malformed trees are parsed as far as possible and any parse/extraction gaps are accumulated as diagnostics. A broken file never takes down the whole analysis.
- Stay standalone and safe. No runtime execution of target code, no network, no external services. Pure static analysis driven by CLI or library API.
In scope:
- Syntactic symbol extraction (functions, classes, objects, methods, structs, enums, interfaces, namespaces) and their visibility/doc metadata.
- Cross-file import resolution, reference resolution, and dependency graph assembly with confidence-weighted edges.
- Cyclic-import detection (Tarjan SCC) and deployment-unit classification.
- MetaCall pod-based deployment manifest generation (
metacall.pods.json) and Function Mesh annotation (metacall.mesh.json) behind themetacall-deployfeature. - External dependency resolution: per-language lockfile/manifest parsing to pin dependencies with exact versions.
- Single-snapshot analysis of a directory tree via CLI or
analyze_graph.
- Architecture review & onboarding. Get a normalized map of every symbol and
its dependencies across a polyglot repo to understand structure quickly.
Run
meta-ast inspecton a checkout and read the JSON/YAML, or open the interactive dashboard frommeta-ast graph --html. - Cyclic dependency guard. Run
meta-ast graphin CI to fail builds that introduce accidental import cycles (Tarjan SCC flags cyclic clusters). - Dependency-graph diffing & refactors. Before splitting a module or deleting a package, generate the graph and confirm what actually depends on it across languages - catch hidden cross-language coupling a grep would miss.
- Pre-commit / code-review signal. Emit the graph or inspect output as a PR artifact so reviewers see structural impact (new symbols, new edges) rather than reading diffs blind.
- Deployment planning for MetaCall / Function Mesh. With the
metacall-deployfeature, thedeploysubcommand turns detected cross-languagemetacall_load_from_*call sites and SCC units into manifests that drive co-deployment vs. independent-function decisions. Requires the feature-enabled install (cargo install meta-ast --features metacall-deploy). - Documentation & visualization. Emit an interactive Cytoscape.js dashboard
(
--html, loaded from a CDN and cached by the browser) to explore ownership, references, and deployment units visually. - Library integration. Consume
meta-astas a crate:analyze_graphreturns aGraphAnalysis(CodeGraph+SccAnalysis) for custom tooling, linters, or report generators.
Extracts all function, class, and object declarations from a codebase.
meta-ast inspect <path> [-l language] [-f json|yaml] [-o output.json]Builds the cross-file dependency graph, resolves imports, and runs Tarjan SCC to identify cyclic clusters and independent deployment units.
meta-ast graph <path> [-l language] [-f json|yaml] [-o graph.json]
meta-ast graph <path> --html # interactive Cytoscape.js dashboard (CDN, browser-cached)
meta-ast graph <path> --datagraph # export detailed datagraph.json (requires --features dataflow)
meta-ast graph <path> --watch # watch mode: continuous re-analysis on file changes (requires --features watch)
meta-ast graph <path> --watch --watch-debounce 100 --html -o graph.html--watch enters a debounced watch loop: on each file change, only changed files
are re-extracted using BLAKE3 cryptographic content fingerprinting (unchanged files reuse cached Arc extractions), then the graph + SCC
are rebuilt. Snapshot IDs increment with each re-analysis tick. Requires
cargo install meta-ast --features watch (or cargo build --features watch).
Scans for cross-language metacall_load_from_* call sites, resolves external dependencies from lockfiles and package manifests, partitions files into same-language pods, and generates deployment artifacts.
cargo build --release --features metacall-deploy
meta-ast deploy <path> [-f json|yaml] [-o ./out] # generate manifests
meta-ast deploy <path> --check # CI validation: verify every cut edge has an RPC stubGenerates two artifacts:
| File | Description |
|---|---|
metacall.pods.json |
Pod manifest: language-based deployment units, inter-pod edges with confidence scores, per-pod dependency lists with pinned versions, and AST node metrics |
metacall.mesh.json |
SCC-derived Function Mesh topology annotation with cross-language call-site attribution |
See docs/DEPLOY.md for scanner details, confidence scoring, pod partitioning, manifest schema, and the fairness check used in CI.
| Document | Description |
|---|---|
| CONTRIBUTING.md | How to build, test, and submit changes |
| docs/ARCHITECTURE.md | High-level pipeline and component boundaries |
| docs/STRUCTURE.md | Module layout, data structures, design patterns |
| docs/DEPLOY.md | Deploy module: scanner, manifests, mesh annotation |
| docs/ROADMAP.md | Phase-by-phase delivery plan |
| docs/adr/ | Architecture Decision Records |
| docs/rfcs/ | Design RFCs |
| docs/specs/ | Requirements and traceability |
- Phase 4 (In Progress): Watch mode complete (feature-gated behind
--features watch). Remaining: C ABI scaffolding. - Phase 5 (Complete):
metacall-deploy- call-site scanning, pod partitioning, dependency resolution, pod manifests, Function Mesh annotation, fairness checking. - Phase 6 (Planned): Language expansion (C#, Java).
Full details in docs/ROADMAP.md.
Performance is measured with criterion
via three benchmark suites (harness = false):
benches/pipeline.rs- end-to-end extraction across the per-language fixtures (python, javascript, typescript, tsx, rust, go, c, cpp, mixed).benches/graph.rs- graph construction, Tarjan SCC on varied topologies (acyclic chains, single/multiple cycles, dense graphs), edge deduplication, and node lookup at scale (up to 10k nodes / 10k duplicates).benches/incremental.rs- cold vs warm incremental re-analysis after file modifications (requires--features watch).
Run them locally:
cargo bench # all suites
cargo bench --bench pipeline # extraction only
cargo bench --bench graph -- --plotting-backend=plotters
cargo bench --bench incremental --features watch # incremental watch benchmarkBenchmarks run on the fixture corpus under tests/fixtures/, so results scale
with that corpus. Typical wall-clock figures (your hardware will vary):
- Per-language extraction of the fixture set completes in low milliseconds.
- SCC and node lookup stay sub-millisecond into the thousands-of-nodes range; edge deduplication is linear in the duplicate count.
For reproducible CI numbers, pin the toolchain (MSRV 1.94.0) and run on a
quiet machine; criterion reports mean/stddev and supports --save-baseline for
regression tracking.
Apache License, Version 2.0. See LICENSE for details.
