```ts
/** The KEY=VALUE pairs of a config file. */
export function parseConfig(text: string): Record<string, string> {
  const config: Record<string, string> = {};
  for (const line of text.split("\n")) {
    if (!line.trim() || line.startsWith("#")) continue;
    const parts = line.split("=", 2);
    const [key, value] = parts.map(part => part.trim());
    if (!key) throw new Error(`Empty key on line: ${line}`);
    config[key] = value;
  }
  return config;
}
```