CHANGELOG.md in cel-0.1.2 vs CHANGELOG.md in cel-0.2.0

@@ -1,6 +1,58 @@
 ## [Unreleased]
 
+## [0.2.0] - 2023-01-17
+
+### Features
+
+#### Timestamp/Duration types
+
+Implementing `Cel::Timestamp` and `Cel::Duration` CEL types, along with support for functions for those types (such as `getDate`, `getDayOfYear`).
+
+```ruby
+Cel::Environment.new.evaluate("timestamp('2022-12-25T00:00:00Z').getDate()") #=> 25
+Cel::Environment.new.evaluate("duration('3600s10ms').getHours()") #=> 1
+```
+
+#### Protobuf-to-CEL conversion
+
+Support for auto-conversion of certain protobuf messages in the `google.protobf` package to CEL types.
+
+https://github.com/google/cel-spec/blob/master/doc/langdef.md#dynamic-values
+
+```ruby
+Cel::Environment.new.evaluate("google.protobuf.BoolValue{value: true}") #=> true
+Cel::Environment.new.evaluate("google.protobuf.Value{string_value: 'bla'}") #=> "bla"
+```
+
+#### Custom Functions
+
+`cel` supports the definition of custom functions in the environment, to be used in expressions:
+
+```ruby
+Cel::Environment.new(foo: Cel::Function(:int, :int, return_type: :int) { |a, b| a + b }).evaluate("foo(2, 2)") #=> 4
+```
+
+### Expression encoding/decoding
+
+Expressions can now be encoded and decoded, to improve storage / reparsing to and from JSON, for example.
+
+```ruby
+enc = Cel::Environment.new.encode("1 == 2") #=> ["op", ...
+store_to_db(JSON.dump(enc))
+
+# then, somewhere else
+env = Cel::Environment.new
+ast = env.decode(JSON.parse(read_from_db))
+env.evaluate(ast) #=> 3
+```
+
+**NOTE**: This feature is only available in ruby 3.1 .
+
+### Bugfixes
+
+* fixed parser bug disallowing identifiers composed "true" or "false" (such as "true_name").
+
 ## [0.1.2] - 2022-11-10
 
 point release to update links in rubygems.
 
 ## [0.1.1] - 2022-08-11