/**
 * Release-channel primitives shared by the self-update command and the
 * startup update check.
 *
 * Kept in the config layer (no shell, theme, or updater imports) so the
 * startup path in main.ts can resolve the channel without pulling in the
 * updater implementation.
 */
import type { Settings } from "./settings";
export declare const UPDATE_CHANNELS: readonly ["stable", "nightly"];
export type UpdateChannel = (typeof UPDATE_CHANNELS)[number];
export declare function isUpdateChannel(value: string): value is UpdateChannel;
/** npm dist-tag backing each release channel. `latest` is the stable tag; nightly publishes never move it. */
export declare function distTagForChannel(channel: UpdateChannel): string;
/**
 * Resolve the machine-local update channel: read the user/global layer only (a
 * project `.gjc/config.yml` `startup.updateChannel` override must never pick
 * the global release channel) and fall back to the stable schema default when
 * the global value is unset or invalid. Used by both the `gjc update` command
 * and the startup update check so a nightly notification can always be
 * satisfied by the same default invocation.
 */
export declare function resolveMachineLocalUpdateChannel(settings: Settings): UpdateChannel;