This is necessary because, in the words of Michael Polanyi, "we can know more than we can tell." Our design choices are not the result of an ineluctable chain of logic; they come from a deeper place, one which is visceral and inarticulate.Polanyi calls this "tacit knowledge", a thing which we only understand as part of something else. When we speak, we do not focus on making sounds, we focus on our words. We understand the muscular act of speech, but would struggle to explain it.To write software, we must learn where to draw boundaries. Good software is built through effective indirection. We seem to have decided that this skill can only be learned through practice; it cannot be taught, except by example. Our decisions may improve with time, but not our ability to explain them. It's true that the study of these questions cannot yield a closed-form solution for judging software design. We can make our software simple, but we cannot do the same to its problem domain, its users, or the physical world. Our tacit knowledge of this environment will always inform our designs.This doesn't mean that we can simply ignore our design process. Polanyi tells us that tacit knowledge only suffices until we fail, and the software industry is awash with failure. Our designs may never be provably correct, but we can give voice to the intuition that shaped them. Our process may always be visceral, but it doesn't have to be inarticulate.And so this book does not offer knowledge, it offers clarity. It is aimed at readers who know Clojure, but struggle to articulate the rationale of their designs to themselves and others. Readers who use other languages, but have a passing familiarity with Clojure, may also find this book useful.

    It presents a learning journey, not definitive guidance. It describes the experiences of a development team with no prior CQRS proficiency in building, deploying (to Windows Azure), and maintaining a sample real-world, complex, enterprise system to showcase various CQRS and ES concepts, challenges, and techniques.The development team did not work in isolation; we actively sought input from industry experts and from a wide group of advisors to ensure that the guidance is both detailed and practical.The CQRS pattern and event sourcing are not mere simplistic solutions to the problems associated with large-scale, distributed systems. By providing you with both a working application and written guidance, we expect you’ll be well prepared to embark on your own CQRS journey.

    The vision behind Clojure is of a radically simple language framework holding together a sophisticated collection of programming features. Learning Clojure involves much more than just learning the mechanics of the language. To really get Clojure you need to understand the ideas underlying this structure of framework and features. You need this book: an accessible introduction to Clojure that focuses on the ideas behind the language as well as the practical details of writing code.

    

    This concise book shows you how to use the API to perform set operations with the DbSet class, handle change tracking and resolve concurrency conflicts with the Change Tracker API, and validate changes to your data with the Validation API.With DbContext, you’ll be able to query and update data, whether you’re working with individual objects or graphs of objects and their related data. You’ll find numerous C# code samples to help you get started. All you need is experience with Visual Studio and database management basics.Use EF’s query capabilities to retrieve data, and use LINQ to sort and filter dataLearn how to add new data, and change and delete existing dataUse the Change Tracker API to access information EF keeps about the state of entity instancesControl change tracking information of entities in disconnected scenarios, including NTier applicationsValidate data changes before they’re sent to the database, and set up validation rulesBypass EF’s query pipeline and interact directly with the database

    

    Cloud computing is rapidly transitioning from a niche technology embraced by startups and tech-forward companies to the foundation upon which enterprise systems build their future. In order to compete in today’s marketplace, organizations large and small are embracing cloud architectures and practices.

    Writing code that handles unexpected errors and still works is really hard. Most of us learn by trial and error. This short book removes the uncertainty. With over 100 pages of content and dozens of working examples, you’ll learn everything from the mechanics of how exceptions work to how to design a robust failure management architecture for your app or library. Whether you are a Ruby novice or a seasoned veteran, Exceptional Ruby will help you write cleaner, more resilient Ruby code.

    It combines the nice features of a scripting language with the powerful features of a production environment—features like persistent data structures and clean multithreading that you'll need for industrial-strength application development.The Joy of Clojure goes beyond just syntax to show you how to write fluent and idiomatic Clojure code. You'll learn a functional approach to programming and will master Lisp techniques that make Clojure so elegant and efficient. The book gives you easy access to hard soft ware areas like concurrency, interoperability, and performance. And it shows you how great it can be to think about problems the Clojure way. Purchase of the print book comes with an offer of a free PDF, ePub, and Kindle eBook from Manning. Also available is all code from the book. What's InsideThe what and why of ClojureHow to work with macrosHow to do elegant application designFunctional programming idiomsWritten for programmers coming to Clojure from another programming background—no prior experience with Clojure or Lisp is required.

    It has become popular in recent years because of its simplicity, conciseness, and clarity. This book teaches functional programming as a way of thinking and problem solving, using Haskell, the most popular purely functional language. Rather than using the conventional (boring) mathematical examples commonly found in other programming language textbooks, the author uses examples drawn from multimedia applications, including graphics, animation, and computer music, thus rewarding the reader with working programs for inherently more interesting applications. Aimed at both beginning and advanced programmers, this tutorial begins with a gentle introduction to functional programming and moves rapidly on to more advanced topics. Details about progamming in Haskell are presented in boxes throughout the text so they can be easily found and referred to.

    This is official Amazon Web Services (AWS) documentation for Amazon Compute Cloud (Amazon EC2).This guide explains the infrastructure provided by the Amazon EC2 web service, and steps you through how to configure and manage your virtual servers using the AWS Management Console (an easy-to-use graphical interface), the Amazon EC2 API, or web tools and utilities.Amazon EC2 provides resizable computing capacity—literally, server instances in Amazon's data centers—that you use to build and host your software systems.

    You'll learn how to use Haskell in a variety of practical ways, from short scripts to large and demanding applications. Real World Haskell takes you through the basics of functional programming at a brisk pace, and then helps you increase your understanding of Haskell in real-world issues like I/O, performance, dealing with data, concurrency, and more as you move through each chapter. With this book, you will:Understand the differences between procedural and functional programming Learn the features of Haskell, and how to use it to develop useful programs Interact with filesystems, databases, and network services Write solid code with automated tests, code coverage, and error handling Harness the power of multicore systems via concurrent and parallel programming You'll find plenty of hands-on exercises, along with examples of real Haskell programs that you can modify, compile, and run. Whether or not you've used a functional language before, if you want to understand why Haskell is coming into its own as a practical language in so many major organizations, Real World Haskell is the best place to start.

    It combines the productivity and expressivity of Ruby with the concurrency and fault-tolerance of Erlang. Elixir makes full use of Erlang's powerful OTP library, which many developers consider the source of Erlang's greatness, so you can have mature, professional-quality functionality right out of the gate. Elixir's support for functional programming makes it a great choice for highly distributed event-driven applications like IoT systems.The Little Elixir & OTP Guidebook gets you started programming applications with Elixir and OTP. You begin with a quick overview of the Elixir language syntax, along with just enough functional programming to use it effectively. Then, you'll dive straight into OTP and learn how it helps you build scalable, fault-tolerant and distributed applications through several fun examples. Come rediscover the joy of programming with Elixir and remember how it feels like to be a beginner again.

    Clojure's clean, careful design lets you write programs that get right to the essence of a problem, without a lot of clutter and ceremony. Clojure is Lisp reloaded. Clojure has the power inherent in Lisp, but is not constrained by the history of Lisp. Clojure is a functional language. Data structures are immutable, and functions tend to be side-effect free. This makes it easier to write correct programs, and to compose large programs from smaller ones. Clojure is concurrent. Rather than error-prone locking, Clojure provides software transactional memory. Clojure embraces Java. Calling from Clojure to Java is direct, and goes through no translation layer. Clojure is fast. Wherever you need it, you can get the exact same performance that you could get from hand-written Java code. Many other languages offer some of these features, but the combination of them all makes Clojure sparkle. Programming Clojure shows you why these features are so important, and how you can use Clojure to build powerful programs quickly.

    New JVM-based languages like Groovy, Scala, and Clojure are redefining what it means to be a Java developer. The core Standard and Enterprise APIs now co-exist with a large and growing body of open source technologies. Multicore processors, concurrency, and massive data stores require new patterns and approaches to development. And with Java 7 due to release in 2011, there's still more to absorb.The Well-Grounded Java Developer is a unique guide written for developers with a solid grasp of Java fundamentals. It provides a fresh, practical look at new Java 7 features along with the array of ancillary technologies that a working developer will use in building the next generation of business software.