The KSoft.Si API sadly doesn't exist anymore, so this library is deprecated.
Depending on what you used it for, you might find the following alternatives interesting:
- User Trust: the ravy.org API (free, application required for non-KSoft users, ksoft users can use their KSoft token but are encouraged to also apply)
- Weather: OpenWeatherMap (limited free tier)
- Weather: Open-Meteo (unlimited free tier without API key)
- Currency: MasterCard (???)