import type { XlsxSink } from '../io/sink';
import { type Workbook } from '../workbook/workbook';
export interface SaveOptions {
    /** Reserved — passes through to the underlying ZIP writer when implemented. */
    compressionLevel?: number;
}
/** Convenience: serialise a Workbook to an in-memory `Uint8Array` xlsx.
 *
 * Browser-safe: this path uses an in-memory `Uint8Array` sink and never
 * touches Node's `Buffer` global, so it works unchanged in browser bundles.
 */
export declare function workbookToBytes(wb: Workbook, opts?: SaveOptions): Promise<Uint8Array>;
/** Save a workbook through the given sink. Returns once `finalize()` resolves. */
export declare function saveWorkbook(wb: Workbook, sink: XlsxSink, _opts?: SaveOptions): Promise<void>;