import type { Result } from './result.js';
export type EnvVar = string & {
    readonly __brand: 'EnvVar';
};
export type EnvVarError = {
    type: 'missing_env_var';
    key: string;
};
export declare const envVar: (key: string, raw: string | undefined) => Result<EnvVar, EnvVarError>;
export declare const envVarUnsafe: (raw: string) => EnvVar;