import type { Checkpoint, Serializer } from '../types.ts';
/**
 * Serialize a Checkpoint to bytes.
 *
 * @example
 * ```ts
 * import { createCheckpoint, serializeCheckpoint } from '@lostgradient/weft';
 *
 * const checkpoint = createCheckpoint('wf-123', '1.0.0');
 * const bytes = serializeCheckpoint(checkpoint);
 * console.log(bytes instanceof Uint8Array); // true
 * console.log(bytes.byteLength > 0);        // true
 * ```
 */
export declare function serializeCheckpoint(checkpoint: Checkpoint, serializer?: Serializer): Uint8Array;
/**
 * Deserialize bytes to a Checkpoint. Throws if invalid.
 *
 * @example
 * ```ts
 * import { createCheckpoint, serializeCheckpoint, deserializeCheckpoint } from '@lostgradient/weft';
 *
 * const checkpoint = createCheckpoint('wf-456', '1.0.0');
 * const bytes = serializeCheckpoint(checkpoint);
 * const restored = deserializeCheckpoint(bytes);
 * console.log(restored.workflowId); // 'wf-456'
 * console.log(restored.step);       // 0
 * ```
 */
export declare function deserializeCheckpoint(bytes: Uint8Array, serializer?: Serializer): Checkpoint;
export declare function validateCheckpointShape(value: unknown): asserts value is Checkpoint;