The most notable features of this new release are:

Windows support is almost there and will probably be shipped in a minor release in the coming weeks.

Here is the full changelog

Major syntax changes

Types are now specified after the identifier + : (#310). This includes:
- Variable declarations
- Function argument definitions
- Catch clauses
- if (...: type as ...)
Arrow function use => instead of ->
Comments and docblocks must now be prefixed by // and /// instead of | and ||
Bitwise or operator is | instead of \
Function type now use fun keyword instead of Function
If a function type has multiple error types, they must be put in parenthesis
Namespace can now be multiple \ separated identifiers
Qualified name now use \ separator instead of .
The float type is renamed to double (#311)
Enum type is declared between <> rather than ()
Protocol list object is conforming to is declared between <> rather than ()
const keyword is renamed to final (#318)

Added

Immutability by default (#139)
- All non-scalar values are immutable by default
- Mutability can be specified in types and for values with the mut keyword
- Object methods that mutate this must be prefixed by mut
- FFI data are considered mutable
Compiler will warn about variable declared with var but never assigned
Object can have final properties (#13)
rg.subsetOf, rg.intersect, rg.union
Tuples (#298): syntaxic sugar over anonymous objects:

const tuple = .{ "john", "james" };

tuple.@"0" == "john";

Checked subscript access to list and strings (gives null when index is out of bound) (#304):

var list = [1, 2, 3];

list[?10] == null;

"hello"[?20] == null;

User input is syntax highlighted in REPL (#217)
REPL handles multilines input (#218)
std\args(): returns the command line arguments with which the script was launched
Compiler is better at inferring empty list/map type from their context (#86)

Enum can now have rg, ud, void, pat as value type
Anonymous object can also omit property name when initial value is a named variable
Mir was updated to 1.0 (#300)

Type checking was not done on object instance property assignments
Http client could not be collected because it kept connection opened to previous requests' domains
Fixed an issue where a JIT compiled function making a lot of function calls would stack overflow

Properties are now retrieved with an index rather than a hashmap lookup (#90) which gives a nice performance boost of about 40% on some benches