tree-sitter · wasm · zero-config

Catch breaking API
changes before they ship.

Parses both sides of a git diff into ASTs, classifies every structural change, and traces call sites to show you exactly what breaks. TypeScript, Go, Python, Java, Rust — Say goodbye to PR merge headaches.

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diff-guardian — Terminal

$ npx dg compare main feature/payments

  Diff-Guardian API Analysis

  Base: main → Head: feature/payments

  [BREAKING] Changes (2)

  ► processPayment (signature_change)

    src/api/payments.ts:42

    R01: Parameter 'currency' was removed.

    Affected call sites (3):

      X  src/checkout/handler.ts:18 — provides 3 arg(s), needs 2

      OK src/invoices/gen.ts:31 — Fixed by developer in this PR

      ✓ 1 other call site(s) have correct arguments

  ► UserConfig (interface_property_removed)

    src/types/config.ts:8

    R26: Property 'timeout' was removed from interface.

  ────────────────────────────────────────

  [STRICT MODE]

  2 breaking changes found. Exiting with code 1.

Tree-Sitter AST Parsing

WASM-compiled grammars parse your old and new source into structured signatures — functions, interfaces, enums, and type aliases.

Lazy Graph Engine

Signature caching and on-demand tracing — only breaking changes trigger call-site resolution. No wasted compute.

CI/CD & IDE Ready

Ships with GitHub Actions workflows, pre-push git hooks, and PR comment reports. Works in your terminal, your editor, and your pipeline.

Multi-Language

One tool for your
entire stack.

Each language has a dedicated translator module built on Tree-Sitter queries. Add a grammar, write a translator — the engine handles the rest.

TypeScript

.ts .tsx

JavaScript

.js .jsx

Python

.py

.go

Java

.java

Rust

.rs

Catch breaking APIchanges before they ship.

Tree-Sitter AST Parsing

Lazy Graph Engine

CI/CD & IDE Ready

One tool for yourentire stack.

Catch breaking API
changes before they ship.

One tool for your
entire stack.