@errcheck/js-core

Internal shared foundation for Errcheck's error-tracking SDKs.

Scope model, client, transport, and rate limiting — shared by every platform package.

This package is not meant to be installed directly. Install one of the platform packages instead — they depend on @errcheck/js-core automatically.

| Package | For | | --- | --- | | @errcheck/js-browser | The browser | | @errcheck/js-server | Server-side JavaScript |

What lives here

graph TD
    Browser["@errcheck/js-browser"] --> Core
    Server["@errcheck/js-server"] --> Core
    subgraph Core["@errcheck/js-core"]
        Scope["Scope model<br/>(global · isolation · current)"]
        Client["Client<br/>(init, capture*, flush)"]
        Transport["Transport<br/>(drop-on-failure, rate-limit aware)"]
    end

• Scope model — global / isolation / current scopes, merged in that precedence order at capture time. See src/scope.ts.
• Client — init, captureException, captureMessage, flush, and the rest of the public API that platform packages re-export as-is.
• Transport — drops rather than retries on failure or an active rate limit; a retry storm during an incident is worse than a few missed events. See src/transports/.
• Async context strategy — an injectable interface (AsyncContextStrategy) that each platform package implements for its own concurrency model. The browser's default is a simple closure-based scope (one JS thread per tab); the server package overrides it with an AsyncLocalStorage-backed implementation for per-request isolation.

License

MIT