/**
 * Append-only JSONL store backing the trace upload WAL.
 */
import { WalRecord } from './types';
/**
 * Promise-chained queue that serializes async tasks one at a time.
 */
declare class SerialQueue {
    private tail;
    run<T>(fn: () => Promise<T>): Promise<T>;
}
export declare const queueWriter: SerialQueue;
export declare function ensureParentDir(filePath: string): Promise<void>;
/**
 * Append a pending trace upload to the WAL.
 */
export declare function appendRecord(record: WalRecord): Promise<void>;
/**
 * Append a tombstone for `id` to the WAL. Logically shadows any earlier
 * `{type:"append"}` line for the same id.
 */
export declare function appendTombstone(id: string): Promise<void>;
/**
 * Append `record` to the dead-letter file (`failed.log.<YYYY-MM-DD>`).
 */
export declare function appendDeadLetter(record: WalRecord): Promise<void>;
/**
 * Replay `queue.log` and return the set of records still considered pending.
 */
export declare function readPending(): Promise<WalRecord[]>;
/**
 * Rewrite `queue.log` to contain only currently-live records.
 */
export declare function compact(): Promise<void>;
/**
 * Size of `queue.log` in bytes, or 0 if the file does not exist.
 * Used by the daemon's idle-shutdown heuristic.
 */
export declare function walSize(): Promise<number>;
export {};