import type { StreamableSignatureSuite } from './types.js';
export declare class SignStream {
    private readonly suite;
    private readonly sk;
    private readonly ctx;
    private hasher;
    private finalized;
    private disposed;
    constructor(suite: StreamableSignatureSuite, sk: Uint8Array, ctx: Uint8Array);
    /**
     * Build the wire-format preamble for `payloadLength`. Available at
     * any point in the stream lifecycle. See
     * docs/signing.md#attached-envelope.
     */
    buildPreamble(payloadLength: number): Uint8Array;
    /** Feed a chunk to the running prehash. */
    update(chunk: Uint8Array): void;
    /**
     * Finalize the running prehash and sign. Returns the signature bytes.
     * Caller writes these as the last segment of the output stream.
     */
    finalize(): Uint8Array;
    /** Wipe lib-owned state. Idempotent. */
    dispose(): void;
}