• Sets and Maps are now backed by Red-Black Trees.
• Added mutable sets and maps (backed by immutable sets and maps for now).
• Added NonEmptyList (Nel) and Validation.
• Added spaceship operator.
• Added binary, octal, and hex literals.
• Added support for underscores in number literals.
• Added use construct to import defs/types/tags from other namespaces.
• Added a check for poorly named type variables.
• Reworked relation and lattice types. They now work more like type aliases.
• Improved the performance of the compiler.
• Extended the standard library.