export interface PutResult {
    version: number;
    created: boolean;
}
export interface CasResult {
    matched: boolean;
    newVersion?: number;
}
export interface DelResult {
    deleted: boolean;
}
export interface QueryRow {
    key: string;
    value: unknown;
    version: number;
    updated_at: number;
}
export interface PutOpts {
    ttl_ms?: number;
    metadata?: unknown;
}
export declare class StateStore {
    private db;
    constructor(dbPath: string);
    private enableWalMode;
    private initSchema;
    private runTtlGc;
    get(namespace: string, key: string): QueryRow | null;
    put(namespace: string, key: string, value: unknown, opts?: PutOpts, producer?: string): PutResult;
    cas(namespace: string, key: string, expectedVersion: number, value: unknown, opts?: PutOpts, producer?: string): CasResult;
    del(namespace: string, key: string): DelResult;
    query(namespace: string, opts?: {
        key_prefix?: string;
        limit?: number;
        offset?: number;
    }): QueryRow[];
    close(): void;
}