Design Principles Behind Smalltalk

The purpose of the Smalltalk project is to provide computer support for the creative spirit in everyone. Our work flows from a vision that includes a creative individual and the best computing hardware available. We have chosen to concentrate on two principle areas of research: a language of description (programming language) that serves as an interface between the models in the human mind and those in computing hardware, and a language of interaction (user interface) that matches the human communication system to that of the computer. Our work has followed a two- to four-year cycle that can be seen to parallel the scientific method: Build an application program within the current system (make an observation) Based on that experience, redesign the language (formulate a theory) Build a new system based on the new design (make a prediction that can be tested) The Smalltalk-80 system marks our fifth time through this cycle. In this article, I present some of the general principles we have observed in the course of our work. While the presentation frequently touches on Smalltalk "motherhood", the principles themselves are more general and should prove useful in evaluating other systems and in guiding future work.

Design OOP Philosophy

Jan 2 2024

 12 Software Architecture Pitfalls and How to Avoid Them

Developing a successful software architecture is simple, but it’s not easy. Understanding QARs and then understanding and making the trade-offs that will maximally satisfy the QARs takes insight and experience, much of which has to be gathered through iterative experimentation on the architecture itself. The process itself is simple, but the trade-offs that need to be considered are often tough, and there are seldom easy answers.

Architecture Best Practices Design

Dec 18 2023

 Cell-Based Architecture — Architecture Pattern

Cell-based architecture in computing involves designing systems that consist of interconnected cells, each cell capable of executing tasks independently. Like the cells in a biological organism, these computing cells have their own processing units, memory, and communication capabilities. They operate in parallel, exchanging information and collaborating to solve complex problems efficiently.

Architecture Design

Sep 4 2023

 How to do distributed locking

As part of the research for my book, I came across an algorithm called Redlock on the Redis website. The algorithm claims to implement fault-tolerant distributed locks (or rather, leases [1]) on top of Redis, and the page asks for feedback from people who are into distributed systems. The algorithm instinctively set off some alarm bells in the back of my mind, so I spent a bit of time thinking about it and writing up these notes.

Design Disributed Systems

Aug 20 2023

 The lost art of software design

“Big design up front is dumb. Doing no design up front is even dumber.” This quote epitomises what I’ve seen during our journey from “big design up front” in the 20th century, to “emergent design” and “evolutionary architecture” in the 21st. In their desire to become “agile”, many teams seem to have abandoned architectural thinking, upfront design, documentation, diagramming, and modelling. In many cases, this is a knee-jerk reaction to the heavy bloated processes of times past, and in others, it’s a misinterpretation and misapplication of the agile manifesto. As a result, many of the software design activities I witness these days are very high-level and superficial in nature. The resulting output, typically an ad hoc sketch on a whiteboard, is usually ambiguous and open to interpretation, leading to a situation where the underlying solution can’t be communicated, assessed, or reviewed. If you’re willing to consider that upfront design is about creating a sufficient starting point, rather than creating a perfect end-state, you soon realise that a large amount of the costly rework and “refactoring” seen on many software development teams can be avoided. Join me for a discussion about the lost art of software design, and how we can reintroduce it to help teams scale and move faster.

Design Video

Aug 13 2023

 An Introduction to Residuality Theory

Residuality theory is a revolutionary new theory of software design that aims to make it easier to design software systems for complex business environments. Residuality theory models software systems as interconnected residues - an alternative to component and process modeling that uses applied complexity science to make managing uncertainty a fundamental part of the design process.

Architecture Design

Jul 5 2023

 Transactions in a Microservice World

Typically, microservice-based applications distribute data widely, especially in cloud-based applications, resulting in distributed applications. This impacts the transactions within these applications. This white paper refreshes the concepts of classical and distributed transactions. Next, we explain how cloud-based applications are affected by distribution. Finally, we present compensation-based transactions as a reliable method for microservice-based application transactions, even in the cloud.

Design Microservices

Jun 16 2023

 How do committees invent?

When I think about design, I more naturally think about it the other way around: how to decompose the whole into a set of parts that will work together to accomplish the system goals. But of course Conway is right that those parts do have to fit together to produce the intended whole again.

Design Philosophy

Jun 14 2023

 How to design software architecture: Top tips and best practices

You wouldn’t want to jump into a project without a solid plan, and software architecture design is no different. By making this process more effective, you can account for all of your requirements properly and give stakeholders the opportunity to provide their input. Using technical visuals and a careful planning process, you can outline your software architecture and design before you get started on a prototype.

Architecture Design

May 21 2023