Czech green card can be naturalized after working in Switzerland for several years.

Five years. You can only apply for naturalization if you have lived in Switzerland for more than five years (these five years must include the year before application). The employer provides a job invitation, and the applicant applies for a B visa to work and live in Switzerland. Switzerland is a landlocked country in central Europe, bordering Germany in the north, France in the west, Italy in the south, Austria and Liechtenstein in the east, and Bern is the seat of the federal government.