/**
 * The RUN PROGRAM record: the source a run was started from, beside its spec.
 *
 * A run used to store no source, so every `resume` and every takeover had to be handed the same
 * file again, and a daemon that hosts drivers had nowhere to read it from after a restart. The
 * source is written here by the driver that pins the run, create-only, and read back by whoever
 * drives the run next. A resume handed DIFFERENT source is a fork (SPEC 14.5); the recorded source
 * is what that comparison is made against, and the hash the language pins each step to is derived
 * from the same bytes.
 *
 * Atomic and create-only: what a run was started from is one fact, decided once. It carries no hash
 * of its own on purpose: the language owns `programHashOf`, core does not depend on the language,
 * and a second hash function here would be a different answer wearing the same name.
 */
import type { KV } from "@nats-io/kv";
export interface RunProgramValue {
    readonly v: 1;
    readonly run: string;
    /** The program, verbatim. */
    readonly source: string;
    /** The file name the source came from, when it came from one. Diagnostic only. */
    readonly file?: string;
    readonly at: number;
}
/**
 * Record a run's source, create-only.
 *
 * A retry with the SAME source is this driver's own earlier attempt and succeeds. A different source
 * under a run that already has one is refused: a run is started from one program, and moving it onto
 * another is a migration, which files its own record.
 */
export declare function recordRunProgram(kv: KV, endpoint: string, value: RunProgramValue): Promise<{
    key: string;
    created: boolean;
}>;
/** The source a run was started from. `undefined` = none recorded (a run started before this
 *  record existed, or one whose start crashed between the activation and the pin). */
export declare function readRunProgram(kv: KV, endpoint: string, runId: string): Promise<RunProgramValue | undefined>;
//# sourceMappingURL=run-program.d.ts.map