Languages and files

JavaScript and TypeScript

JS, TS, JSX and TSX are parsed with Babel and get the full treatment described in What a snapshot captures: signatures, members, hooks and a resolved call graph.

Framework shapes

• Next.js App Router. app/**/page.tsx and route.ts become route symbols carrying the URL they serve. Route groups (shell) and parallel slots @modal are dropped, [id] becomes :id, and catch-alls become *slug. Handlers exported under a method alias (export { handler as GET }) are recorded once per method.
• tRPC. createTRPCRouter({ … }) yields one procedure symbol per key, tagged query/mutation and protected/public, with its zod input fields as members. Schemas declared elsewhere are followed through imports, .extend, .merge, .pick, .omit and shape spreads. Mounted sub-routers become references edges.

Python

Python files are analysed with the interpreter's own ast module:

• module-level functions, with annotations and defaults in their signatures
• classes, with members, base classes and pydantic-style typed fields tagged schema
• constants, and calls between project modules (relative imports included)

Decorators become roles (lru_cache, async). Route decorators become route symbols: FastAPI's @app.post("/classify") reads as POST /classify, and Flask's @app.route("/items", methods=["POST"]) works too. Visibility follows __all__ when defined, otherwise the leading-underscore rule.

One interpreter run covers the whole scan. A file that will not parse still gets a hash-only symbol and an entry in the snapshot's errors.

Config, schema and migrations

File	Symbols
schema.prisma	One per model (fields, @@index/@@unique, relations as references edges), enum and datasource/generator block
prisma/migrations/**/*.sql	One per migration, with a one-line summary of each statement
package.json	scripts, dependencies, devDependencies. A bump reads as -react@^18 +react@^19
.env.example	Variable names only, never values
compose.yaml	One per service, with its settings
pyproject.toml, Cargo.toml	One per section, plus one per dependency list

Tests

Test files are scanned like any other source. Each top-level describe (or suite/context) becomes a test symbol whose members are its cases. A suite's edges record what it exercises, with the runner's own API filtered out. That is what lets review say whether a changed symbol had a test change.

Everything else

Go, Rust, Java, Kotlin, C#, Swift, PHP and shell get a shallow declaration scan: top-level functions, methods (named after their receiver, Server.Start), types with their fields or methods, and constants, using each language's own visibility rule. A Rust impl block merges into the type it implements.

The shallow scan records no call graph and does not go deeper than one level of nesting. It shows what changed where, not the depth TypeScript or Python get.