* fix: multiple transitions in a single event with the same to and from states (see [issue #372](https://github.com/aasm/aasm/issues/372) and [issue #362](https://github.com/aasm/aasm/issues/362) for details, fixed with [pull-request #408](https://github.com/aasm/aasm/pull/408), thanks to [@dathanb](https://github.com/dathanb))
* fix: passing nil as a argument to callbacks (see [issue #404](https://github.com/aasm/aasm/issues/404) for details, fixed with [pull-request #406](https://github.com/aasm/aasm/pull/406), thanks to [@yogeshjain999](https://github.com/yogeshjain999))
* fix: Scopes when states are defined as a series of symbols (see [issue #397](https://github.com/aasm/aasm/pull/397) for details, thanks to [@evheny0](https://github.com/evheny0))
* fix: permissible states not respecting guard parameters (see [issue #388](https://github.com/aasm/aasm/issues/388)) with [pull-request #389](https://github.com/aasm/aasm/pull/389)
* support `logger` configuration (see [issue #370](https://github.com/aasm/aasm/pull/370) for details, thanks to [@HoyaBoya](https://github.com/HoyaBoya))
* support configuration to let bang transitions fail if object is invalid (see [issue #366](https://github.com/aasm/aasm/pull/366) and [issue #262](https://github.com/aasm/aasm/issues/262) for details, thanks to [@Wildebeest](https://github.com/Wildebeest))
* fix: suppress warnings when using ActiveRecord enums feature (see [issue #346](https://github.com/aasm/aasm/pull/346) for details, thanks to [@110y](https://github.com/110y), and [issue #353](https://github.com/aasm/aasm/pull/353) for details, thanks to [@nathanstitt](https://github.com/nathanstitt))
* fix: handle array of success callbacks for transitions properly (see [issue #363](https://github.com/aasm/aasm/pull/363) for details, thanks to [@shunichi](https://github.com/shunichi))
* support `permitted: false` for states and events query/inspection methods (see [issue #364](https://github.com/aasm/aasm/pull/364) for details, thanks to [@hspazio](https://github.com/hspazio))
* fix: some issues with RubyMotion (see [issue #320](https://github.com/aasm/aasm/pull/320) and [issue #343](https://github.com/aasm/aasm/pull/343) for details, thanks to [@Infotaku](https://github.com/Infotaku))
* fix: transitions now work in dup'ed copies (see [issue #325](https://github.com/aasm/aasm/pull/325) which fixes [issue #273](https://github.com/aasm/aasm/pull/273) for details, thanks to [@lingceng](https://github.com/lingceng))
* fix: allow skipping the `aasm_ensure_initial_state` callback (see [issue #326](https://github.com/aasm/aasm/pull/326) for details, thanks to [@sineed](https://github.com/sineed))
* fix: has_many association helper works again for Mongoid (see [issue #333](https://github.com/aasm/aasm/pull/333) which fixes [issue #332](https://github.com/aasm/aasm/pull/332) for details, thanks to [@anilmaurya](https://github.com/anilmaurya))
* improve performance / refactor: load and run only code which is needed (see [issue #336](https://github.com/aasm/aasm/pull/336) for details, thanks to [@csmuc](https://github.com/csmuc))
* improve: warn when overriding an existing method (see [issue #340](https://github.com/aasm/aasm/pull/340) which fixes [issue #335](https://github.com/aasm/aasm/pull/335) for details, thanks to [@pirj](https://github.com/pirj))
* fix: correct error message (by not evaluating the current state lazily) (see [issue #341](https://github.com/aasm/aasm/pull/341) which fixes [issue #312](https://github.com/aasm/aasm/pull/312) for details, thanks to [@pirj](https://github.com/pirj))
* addition: support for Redis as persistence layer (see [issue #190](https://github.com/aasm/aasm/pull/190) for details, thanks to [@javajax](https://github.com/javajax))
* addition: support transition `:success` callbacks (see [issue #239](https://github.com/aasm/aasm/pull/239) which fixes [issue #236](https://github.com/aasm/aasm/pull/236) for details, thanks to [@brega](https://github.com/brega))
* addition: support for namespacing methods and state names (see [issue #259](https://github.com/aasm/aasm/pull/259) for details, thanks to [@allspiritseve](https://github.com/allspiritseve))
* addition: support for defining multiple states in one line (see [issue #288](https://github.com/aasm/aasm/pull/288) which fixes [issue #146](https://github.com/aasm/aasm/pull/146) for details, thanks to [@HParker](https://github.com/HParker))
* fix: uninitialised constant when running Rails generator (see [issue #339](https://github.com/aasm/aasm/pull/339) for details, thanks to [@long-long-float](https://github.com/long-long-float))
* add support for callback classes (`after` only) (see [issue #316](https://github.com/aasm/aasm/pull/316) for details, thanks to [@mlr](https://github.com/mlr))
* allow easier extension of _AASM_ (utilising the idea of _ApplicationRecords_ from _Rails 5_) (see [issue #296](https://github.com/aasm/aasm/pull/296) for details, thanks to [@mlr](https://github.com/mlr))
* support pessimistic locking for _ActiveRecord_ (see [issue #283](https://github.com/aasm/aasm/pull/283) for details, thanks to [@HoyaBoya](https://github.com/HoyaBoya))
* fix: support database sharding for _ActiveRecord_ (see [issue #289](https://github.com/aasm/aasm/pull/289) for details, thanks to [@scambra](https://github.com/scambra))
* fix: some issues with RubyMotion (see [issue #318](https://github.com/aasm/aasm/pull/318) for details, thanks to [@Infotaku](https://github.com/Infotaku))
* fix: Rails generator now features the correct namespace (see [issue #328](https://github.com/aasm/aasm/pull/328) and [issue #329](https://github.com/aasm/aasm/pull/329) for details, thanks to [@anilmaurya](https://github.com/anilmaurya))
* add support for [dynamoid](http://joshsymonds.com/Dynamoid/) (see [issue #300](https://github.com/aasm/aasm/pull/300) for details, thanks to [@LeeChSien](https://github.com/LeeChSien))
* make compatible with [RubyMotion](http://www.rubymotion.com) (see [issue #315](https://github.com/aasm/aasm/pull/315) for details, thanks to [@Infotaku](https://github.com/Infotaku))
* improve error handling in case of an exception during transitioning (see [issue #275](https://github.com/aasm/aasm/pull/275) for details, thanks to [@chriswoodrich](https://github.com/chriswoodrich))
* rspec matcher `on_event` now supports arguments (see [issue #309](https://github.com/aasm/aasm/pull/309) for details, thanks to [@zacviandier](https://github.com/zacviandier))
* fix: permitted states now respect guards (see [issue #308](https://github.com/aasm/aasm/pull/308) for details, thanks to [@eebs](https://github.com/eebs))
* fix: reloading the env now doesn't add callbacks twice anymore (see [issue #311](https://github.com/aasm/aasm/pull/311) for details, thanks to [@lingceng](https://github.com/lingceng))
* add new callbacks: transactions, all events, ensure (see [issue #282](https://github.com/aasm/aasm/issues/282) for details, thanks to [@HoyaBoya](https://github.com/HoyaBoya))
* fix: make sure the column is actually present for _ActiveRecord_ enums (see [issue #265](https://github.com/aasm/aasm/issues/265) and [issue #152](https://github.com/aasm/aasm/issues/152) for details, thanks to [@anilmaurya](https://github.com/anilmaurya))
* add generators to configure active_record and mongoid after install (see [issue #261](https://github.com/aasm/aasm/issues/261) for details, thanks to [@anilmaurya](https://github.com/anilmaurya))
* make sure to use override configuration options if state machine is defined more than once (see [issue #287](https://github.com/aasm/aasm/issues/287) for details)
* add RSpec matcher `transition_from` (see [issue #178](https://github.com/aasm/aasm/issues/178) for details, thanks to [@thomasstephane](https://github.com/thomasstephane))
* add support for rejecting certain events on inspection (see [issue #272](https://github.com/aasm/aasm/issues/272) for details, thanks to [@dubroe](https://github.com/dubroe))
* add support global transation callbacks (see [issue #221](https://github.com/aasm/aasm/issues/221) and [issue #253](https://github.com/aasm/aasm/issues/253) for details)
* add support (bugfix) for Mongoid >= 5.0 (see [issue #277](https://github.com/aasm/aasm/issues/277) and [issue #278](https://github.com/aasm/aasm/issues/278) for details)
* add support for multiple state machines per class (see [issue #158](https://github.com/aasm/aasm/issues/158) and [issue #240](https://github.com/aasm/aasm/issues/240) for details)
* special thanks to [@evadne](https://github.com/evadne) for testing this feature, and providing comments and patches (see [issue #245](https://github.com/aasm/aasm/issues/245) for details)
* support turning off and on the configuration option for `no_direct_assignment` (see [issue #223](https://github.com/aasm/aasm/issues/223) for details)
* event arguments are now passed to `:after_commit` callbacks as well (see [issue #238](https://github.com/aasm/aasm/pull/238), thanks to [@kuinak](https://github.com/kuinak))
* event arguments are now passed to state callbacks as well (not only to event callbacks) (see [issue #219](https://github.com/aasm/aasm/issues/219), thanks to [@tobithiel](https://github.com/tobithiel))
*`AASM::InvalidTransition` now references the current object (with the state machine) and the _AASM_ event name (see [issue #217](https://github.com/aasm/aasm/issues/217), thanks to [@awsmsrc](https://github.com/awsmsrc))
* bugfix: do not update unloaded state for [Sequel](http://sequel.jeremyevans.net/) (see [issue #218](https://github.com/aasm/aasm/issues/218), thanks to [@godfat](https://github.com/godfat))
* bugfix: initialize the aasm state column after initialization of the _Mongoid_ instance (see [issue #206](https://github.com/aasm/aasm/issues/206), thanks to [@Shwetakale ](https://github.com/Shwetakale ))
* added support for mongomapper ORM (see [issue #203](https://github.com/aasm/aasm/issues/203), thanks to [@reidmorrison ](https://github.com/reidmorrison ))
* bugfix: `false` is treated as uninitialised state (same as `nil`) (see [issue #195](https://github.com/aasm/aasm/issues/195) for details)
* bugfix: an event's `:error` callback now retrieves all arguments passed to the event (see [issue #196](https://github.com/aasm/aasm/issues/196) for details)
* bugfix: initialize the aasm state column after initialization of the _ActiveRecord_ instance only if the attribute has been loaded (see [issue #193](https://github.com/aasm/aasm/issues/193) for details)
* bugfix: initialize the aasm state column after initialization of the _ActiveRecord_ instance (see [issue #191](https://github.com/aasm/aasm/issues/191) for details)
* bugfix: avoid Rails autoloading conflicts (see [issue #137](https://github.com/aasm/aasm/issues/137) and [issue #139](https://github.com/aasm/aasm/issues/139) for details)
* support `if` and `unless` guard syntax: (see [issue #179](https://github.com/aasm/aasm/issues/179) and [issue #181](https://github.com/aasm/aasm/issues/181)), thanks to [@bigtunacan](https://github.com/bigtunacan)
* allow retrieving the current event (`aasm.current_event`) (see [issue #159](https://github.com/aasm/aasm/issues/159) and [issue #168](https://github.com/aasm/aasm/issues/168))
* bugfix: avoid conflicts with `failed` and `fired` event names (see [issue #157](https://github.com/aasm/aasm/issues/157)), thanks to [@MichaelXavier](https://github.com/MichaelXavier)
* bugfix: not using transactions unless saving to the database (see [issue #162](https://github.com/aasm/aasm/issues/162) and [issue #164](https://github.com/aasm/aasm/issues/164)), thanks to [@roberthoner](https://github.com/roberthoner)
* bugfix: `after_commit` should only run if saving to the database (see [issue #151](https://github.com/aasm/aasm/issues/151)), thanks to [@ivantsepp](https://github.com/ivantsepp)
* support for Rails 4.1 enum fields (see [issue #124](https://github.com/aasm/aasm/issues/124), thanks to [@bkon](https://github.com/bkon))
* bugfix: allow lazy-evaluation for Rails 3 scopes (see [issue #144](https://github.com/aasm/aasm/issues/144), thanks to [@laurens](https://github.com/laurens))
* bugfix: permissible_events and events did not contain events with an empty "from" transition (see [issue #140](https://github.com/aasm/aasm/issues/140) and [issue #141](https://github.com/aasm/aasm/issues/141), thanks to [@daniel-rikowski](https://github.com/daniel-rikowski))
* support [Sequel](http://sequel.jeremyevans.net/) (see [issue #119](https://github.com/aasm/aasm/issues/119), thanks to [@godfat](https://github.com/godfat))
* bugfix: don't require ActiveRecord for localizing AASM event and state name (see [issue #113](https://github.com/aasm/aasm/issues/113), thanks to [@silentshade](https://github.com/silentshade))
* initialize the state even if validation is skipped (for ActiveRecord and Mongoid persistence) (see [issue #103](https://github.com/aasm/aasm/issues/103), thanks to [@vfonic](https://github.com/vfonic) and [@aaronklaassen](https://github.com/aaronklaassen))