/** Layout of the on-disk store, all under `<project>/.nightwatch/`. */
export interface StorePaths {
    readonly root: string;
    readonly ledgerDir: string;
    readonly headsDir: string;
    readonly locksDir: string;
    readonly spillDir: string;
    /** Created on demand by `nightwatch keygen`, not by ensureStore. */
    readonly keysDir: string;
    readonly metaFile: string;
    readonly checkpointsFile: string;
    readonly errorLog: string;
}
export declare const STORE_DIRNAME = ".nightwatch";
export declare function storePathsAt(projectRoot: string): StorePaths;
export declare function ensureStore(paths: StorePaths): void;
/** Walk upward from `start` until a directory containing `.nightwatch/` is found. */
export declare function findProjectRoot(start: string): string;
export declare function ledgerFile(paths: StorePaths, session: string): string;
export declare function headFile(paths: StorePaths, session: string): string;
/** Session ids come from external payloads — never let them traverse paths. */
export declare function sanitizeSession(session: string): string;