/**
 * A per-directory fingerprint cache backed by a JSON file on disk.
 *
 * Each fingerprinted directory gets its own cache file in ~/.cdk/cache/fingerprints/.
 * Entries map file metadata (inode+mtime+size) to content fingerprints.
 */
export declare class FingerprintDiskCache {
    private cache;
    private dirty;
    private cacheFile;
    /**
     * Create a FingerprintDiskCache
     *
     * The `directoryPath` argument is expected to be pre-resolved to an absolute path.
     */
    constructor(directoryPath: string);
    /**
     * Look up a cached fingerprint or compute it.
     */
    obtain(cacheKey: string, calcFn: () => string): string;
    /**
     * Persist the cache to disk.
     */
    save(): void;
    private _load;
    private _evict;
    /** Remove oldest cache files if the directory exceeds MAX_CACHE_FILES */
    private _evictCacheDir;
}