interface ShellSnapshotCacheOptions {
    tempRoot: string;
    home: string | (() => string);
    platform: NodeJS.Platform;
}
declare function createShellSnapshotCache(options: ShellSnapshotCacheOptions): {
    getOrCreateSnapshot(shell: string, env: Record<string, string | undefined>): Promise<string | null>;
    cleanup(): Promise<void>;
};
/** @internal Test-only factory for isolated filesystem and platform assertions. */
export declare const createShellSnapshotCacheForTesting: typeof createShellSnapshotCache;
/**
 * Create a shell snapshot, caching the result.
 * Returns the path to the snapshot file, or null if creation failed.
 */
export declare function getOrCreateSnapshot(shell: string, env: Record<string, string | undefined>): Promise<string | null>;
export {};