uuid

RFC4122 (v1, v4, v5, v6, v7, v8) UUID Generator and Parser for Dart

$dart pub add uuid

Official docs outline

Extra Credit builds an outline of uuid's docs the first time your work uses it. Until then, start at the official documentation.

mockito A mock framework inspired by Mockito with APIs for Fakes, Mocks, behavior verification, and stubbing.
path_provider Flutter plugin for getting commonly used locations on host platform file systems, such as the temp and app data directories.
args Library for defining parsers for parsing raw command-line arguments into a set of options and values using GNU and POSIX style options.
shared_preferences Flutter plugin for reading and writing simple key-value pairs. Wraps NSUserDefaults on iOS and SharedPreferences on Android.
crypto Implementations of SHA, MD5, and HMAC cryptographic functions.
logging Provides APIs for debugging and error logging, similar to loggers in other languages, such as the Closure JS Logger and java.util.logging.Lo
analyzer This package provides a library that performs static analysis of Dart code.
equatable A Dart package that helps to implement value based equality without needing to explicitly override == and hashCode.
yaml A parser for YAML, a human-friendly data serialization standard
cupertino_icons Default icons asset for Cupertino widgets based on Apple styled icons
url_launcher Flutter plugin for launching a URL. Supports web, phone, SMS, and email schemes.
provider A wrapper around InheritedWidget to make them easier to use and more reusable.