• Added flat_map method to Promise
• Added zip method to Promise
• Fixed bug with logging in Actor
• Improvements to Promise tests
• Removed actor-experimental warning
• Added an IndirectImmediateExecutor class
• Allow disabling auto termination of global executors
• Fix thread leaking in ThreadLocalVar (uses Ref gem on non-JRuby systems)
• Fix thread leaking when pruning pure-Ruby thread pools
• Prevent Actor from using an ImmediateExecutor (causes deadlock)
• Added missing synchronizations to TimerSet
• Fixed bug with return value of Concurrent::Actor::Utils::Pool#ask
• Fixed timing bug in TimerTask
• Fixed bug when creating a JavaThreadPoolExecutor with minimum pool size of zero
• Removed confusing warning when not using native extenstions
• Improved documentation