Examples

One minimal hub per supported language. Each shows an at: anchor and the rule that always holds: quiet on cosmetics (formatting, comments, consistent renames), loud on logic. Run surf verify once to seal the hash, then surf check gates it.

The anchor grammar and the verify loop are covered in Authoring hubs.

TypeScript

anchors:
  - claim: rotation is single-use; a reused token triggers global logout
    at: src/auth/refresh.ts > TokenService > rotate

• Rename a local, reformat, add a comment → no fire.
• Change if (token.used) to if (token.used || token.expired) → fires.

JavaScript / JSX

anchors:
  - claim: cart total applies the member discount before tax
    at: src/cart.js > computeTotal

JS/JSX is parsed by the TS-family grammar, so const computeTotal = (...) => { ... } resolves the same as a function declaration.

• Drop an await, flip * to + → fires.

Rust

anchors:
  - claim: combining site hashes is order-sensitive
    at: surf-core/src/hash.rs > combine_site_hashes

Type > method walks into an impl: at: surf-cli/src/workspace.rs > Workspace > discover.

• Change < to <=, alter a literal value → fires.

Python

anchors:
  - claim: retries use exponential backoff capped at 30s
    at: api/client.py > Client > _request

Decorators are transparent for resolution — @retry above def _request doesn’t change which symbol the anchor finds — but they are part of the hashed span, so a decorator swap (@retry → @retry_with_jitter) fires.

• Change the backoff base or the cap → fires.

Non-callables anchor too — module constants, type aliases, and class attributes:

anchors:
  - claim: retries fire on exactly these status codes
    at: api/client.py > RETRYABLE_STATUS_CODES
  - claim: the SDK supports these chains
    at: api/types.py > Chain

• Add or remove a status code, or change a Chain member → fires.

Go

anchors:
  - claim: the receiver validates the signature before decoding
    at: internal/webhook.go > Handler > Verify

Go methods attach by receiver, so the anchor is Type > Method even though the method isn’t nested in the type. Top-level funcs/types use a single segment: cmd/main.go > Run.

• Reorder unrelated declarations → no fire. Change the comparison in Verify → fires.