/**
 * §5.8 shipped compression posture for the direct segment endpoint:
 * negotiate `Content-Encoding` from the request's `Accept-Encoding`
 * (zstd preferred, gzip fallback, identity when the client offers
 * neither), feature-detecting the runtime's codecs — zero dependencies.
 *
 * Segment bytes are stored and content-addressed UNCOMPRESSED (§5.1);
 * this is a per-response serving concern only. It is never applied to
 * stored objects or the signed-URL path (§5.8: presigned GETs serve the
 * addressed bytes verbatim; edge compression is a deployment concern).
 *
 * Decision data (2026-07-03, 100k-row bench table, Bun 1.3): rows
 * segments 6.2× in 8 ms (zstd) / 7.7× in 42 ms (gzip); sqlite images
 * 3.4× in 14 ms (zstd) / 51 ms (gzip); client decompression ≤ 8 ms.
 */
export type SegmentContentEncoding = 'zstd' | 'gzip';
export interface EncodedSegmentBody {
    readonly bytes: Uint8Array;
    /** Absent ⇒ identity (no `Content-Encoding` header). */
    readonly contentEncoding?: SegmentContentEncoding;
}
/**
 * Compress a buffered segment body per §5.8. Returns the original bytes
 * (identity) when the client offered no supported encoding, the body is
 * tiny, or the runtime has no codec.
 */
export declare function encodeSegmentBody(bytes: Uint8Array, acceptEncoding: string | undefined): EncodedSegmentBody;