major software change was removal of the requirement that chunks must be specified based on predefined chunk-types. The chunk-type mechanism was not removed, but changed from being a required construct of the architecture to being an optional syntactic mechanism in the software. This allowed for more flexibility in knowledge representation for modeling tasks that require learning novel information and extended the functionality provided through dynamic pattern matching now allowing models to create new "types" of chunks. This also lead to a simplification of the syntax required for specifying the actions in a production because all the actions now have the same syntactic form. The ACT-R software has also been subsequently updated to include a remote interface based on JSON RPC 1.0. That interface was added to make it easier to build tasks for models and work with ACT-R from languages other than Lisp, and the tutorial included with the software has been updated to provide Python implementations for all of the example tasks performed by the tutorial models. Workshop and summer school In 1995, Carnegie Mellon University began hosting their Annual ACT-R Workshop and Summer School. Their ACT-R Workshop is currently hosted at the annual MathPsych/ICCM Conference, and their Summer School is hosted on-campus with a virtual attendance option at Carnegie Mellon University. Spin-offs The long development of the ACT-R theory gave birth to a certain number of parallel and related projects. The most important ones are the PUPS production system, an initial implementation of Anderson's theory, later abandoned; and ACT-RN, a neural network implementation of the theory developed by Christian Lebiere. Lynne M. Reder, also at Carnegie Mellon University, developed SAC in the early 1990s, a model of conceptual and perceptual aspects of memory that shares many features with the ACT-R core declarative system, although differing in some assumptions. For his dissertation at Carnegie Mellon University, Christopher L. Dancy developed, and successfully defended in 2014, ACT-R/Phi, an implementation of ACT-R with added physiological modules which enable ACT-R to interface with human physiological processes. Notes References Anderson, J. R. (2007). How can the human mind occur in the physical universe? New York, NY: Oxford University Press. . Anderson, J. R., Bothell, D., Byrne, M. D., Douglass, S., Lebiere, C., & Qin, Y . (2004). An integrated theory of the mind. Psychological Review'', 1036–1060. External links Official ACT-R website with a lot of online material, including the source code, list of