/** Canonical project source directory for application preloads. */
export declare const PROJECT_PRELOAD_DIR = "src/preload";
/** Compatibility-only project-root directory used by older applications. */
export declare const LEGACY_PROJECT_PRELOAD_DIR = "preload";
/** Directory name relative to the configured build output. */
export declare const PROJECT_PRELOAD_OUTPUT_DIR = "preload";
/** Default production output directory for project preloads. */
export declare const DIST_PRELOAD_DIR = "dist/preload";
export declare const PROJECT_PRELOAD_FILE_PATTERN: RegExp;
export type ProjectPreloadDirectoryKind = "canonical" | "legacy";
export interface ProjectPreloadDirectory {
    path: string;
    relativePath: string;
    kind: ProjectPreloadDirectoryKind;
    hasSourceFiles: boolean;
}
/**
 * Resolves a project preload source directory without silently combining the
 * canonical and legacy locations. Preloads are side-effectful and their order
 * is part of application startup, so two populated locations are a migration
 * error rather than an implicit merge.
 */
export declare function resolveProjectPreloadDirectory(rootDir: string): ProjectPreloadDirectory | null;
export declare function formatLegacyProjectPreloadWarning(): string;