/** Release resources and stop accepting work. May be async. */
export type ShutdownTask = () => void | Promise<void>;
export interface ProcessGuardOptions {
    /** Transport id, used as the log prefix so the line says WHICH bridge died. */
    name: string;
    /** Runs once, on the first signal, before the process exits. */
    onShutdown?: ShutdownTask;
    /** Test seam; production ends the process. */
    exit?: (code: number) => void;
    /** How long a shutdown task may take before the process leaves anyway.
     *  Defaults to `SHUTDOWN_GRACE_MS`; tests shorten it. */
    graceMs?: number;
}
/** A shutdown task that hangs must not hold the terminal hostage. */
export declare const SHUTDOWN_GRACE_MS = 5000;
export declare function installProcessGuards(opts: ProcessGuardOptions): void;