mkcert is a simple tool for making locally-trusted development certificates. It requires no configuration. Using certificates from real certificate authorities (CAs) for development can be dangerous or impossible (for hosts like localhost or 127.0.0.1), but self-signed certificates cause trust errors. Managing your own CA is the best solution, but usually involves arcane commands, specialized knowledge and manual steps. mkcert automatically creates and installs a local CA in the system root store, and generates locally-trusted certificates. mkcert does not automatically configure servers to use the certificates, though, that's up to you.