Martin Fowler

APRIL 21, 2024

Big Sur, CA

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190

Martin Fowler

APRIL 10, 2024

Alessio Ferri and Tom Coggrave complete their article about introducing seams into mainframe systems by looking how we can use data replication.

Data 219

Data System 219

Martin Fowler

APRIL 4, 2024

Alessio Ferri and Tom Coggrave move on to analyzing the internal seams of the application by treating the database as a coarse-grained seam. They describe how they introduced seams into the database readers and writers.

Applications 202

Applications 202

Martin Fowler

APRIL 4, 2024

Mainframe processing is often organized into pipelines of batch processes consuming and creating data files. Alessio Ferri and Tom Coggrave show a couple of ways they found to introduce seams into these pipelines , so that processing could be replaced by steps in a replacement platform.

Organization 212

Organization Data 212

Martin Fowler

MARCH 28, 2024

As the enmuskification of Twitter continues, I’ve increasingly heard that more people are using LinkedIn to keep up with new professional material. So, a couple of weeks ago, I set up my LinkedIn account , so people can follow me on that platform. I’ve always avoided LinkedIn - I’ve found the whole vibe of connections rather off-putting. I get too much spam from people wanting to connect as it is.

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194

Martin Fowler

MARCH 27, 2024

John Kordyback, a treasured colleague and friend, died last week, aged 64.

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291

Martin Fowler

MARCH 27, 2024

Alessio Ferri and Tom Coggrave start detailing the seams they explored with two areas of external interfaces. Batch input of files are copied to new implementations while comparing the output of the processing pipelines. API access points can be covered with a proxy and traffic gradually directed to the new implementation.

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Martin Fowler

MARCH 26, 2024

Mainframe systems continue to run much of the world's computing workload, but it's often difficult to add new features to support growing business needs. Furthermore the architectural challenges that make them slow to enhance also make them hard to replace. To reduce the risk involved, we use an incremental approach to legacy displacement, gradually replacing legacy capabilities with implementations in modern technology.

Architecture 295

Architecture System Strategy Technology 295

Martin Fowler

MARCH 19, 2024

Abi Noda and Tim Cochran complete their article on qualitative metrics by outlining how to capture them effectively. They discuss the mental steps that people go through as they respond to a survey and provide a template to get started when assessing developer experience. A final section looks at how qualitative and quantitative work together: often by starting with qualitative metrics to establish baselines and determine where to focus, followed with quantitative metrics to drill deeper into sp

Metrics 183

Metrics How To Survey Development 183

Martin Fowler

MARCH 15, 2024

From time to time people ask me for a copy of the code I used in the opening chapter of Refactoring , so they can follow along themselves. I had Reasons for not providing this code, specifically laziness. Fortunately Emily Bache is more dedicated, and she has set up a github repository - the Theatrical Players Refactoring Kata - with the code, and enough tests to make it reasonable to do the refactoring.

Video 170

Video Testing 170

Martin Fowler

MARCH 13, 2024

Abi Noda and Tim Cochran continue their discussion on using qualitative metrics to assess the productivity of development teams. In this installment they classify qualitative metrics into attitudinal and behavioral metrics. We also see that qualitative metrics allow you to measure things that are otherwise unmeasurable, provide missing visibility, and supply necessary context for quantitative data.

Metrics 179

Metrics Data Development 179

Martin Fowler

MARCH 12, 2024

Measuring developer productivity is a difficult challenge. Conventional metrics focused on development cycle time and throughput are limited, and there aren't obvious answers for where else to turn. Qualitative metrics offer a powerful way to measure and understand developer productivity using data derived from developers themselves. Abi Noda and Tim Cochran begin their discussion by explaining what a qualitative metric is and why we shouldn't reject them for being subjective or unreliable.

Development 292

Development Metrics Data 292

Martin Fowler

MARCH 5, 2024

When we gradually replace a legacy system, we have plenty of cases where the legacy system and its replacement need to interact. Since these legacy systems are often difficult, and costly, to change, we need a mechanism that can integrate elements of the replacement while minimizing the impact to the legacy system. Ian Cartwright, Rob Horn, and James Lewis explain how we can use Event Interception on state-changing events, allowing us to forward them to the replacement.

System 284

System 284

Martin Fowler

FEBRUARY 27, 2024

Improvements in communications technology have led an increasing number of teams that work in a Remote-First style, a trend that was boosted by the forced isolation of Covid-19 pandemic. But a team that operates remotely still benefits from face-to-face gatherings, and should do them every few months. Remote-first teams have everyone in a separate location, communicating entirely by email, chat, video and other communication tools.

Travel 147

Travel Video Hotels System Architecture 147

Martin Fowler

FEBRUARY 13, 2024

LLM engineering involves much more than just prompt design or prompt engineering. Here David Tan and Jessie Wang reflect on how regular engineering practices such as testing and refactoring helped them deliver a prototype LLM application rapidly and reliably.

Artificial Inteligence 273

Artificial Inteligence Engineering Applications Development 273

Martin Fowler

JANUARY 25, 2024

I’ve been using Emacs for many years, using it for any writing for my website, writing my books, and most of my programming. (Exceptions have been IntellJ IDEA for Java and RStudio for R.) As such I’ve been happy to see a lot of activity in the last few years to improve Emacs’s capabilities, making it feel rather less than a evolutionary dead end. One of the biggest improvements to my Emacs experience is using regexs for completion lists.

Tools 135

Tools Virtualization Programming Company 135

Martin Fowler

JANUARY 24, 2024

Tim and Premand begin their discussion of how to get out of the difficulties of onboarding by explaining how to create a path to effectiveness for new hires. Such a path outlines the needs of employee and how the onboarding process should fulfill them.

How To 192

How To 192

Martin Fowler

JANUARY 23, 2024

The last year has been a hard one for the technology industry, which faced its greatest waves of cutbacks and layoffs since the dotcom crash at the beginning of the century. As 2024 begins, we're seeing the early signs of a turn-around, which hopefully means technology organizations will soon be thinking of hiring again. Should such happy days return, firms will again run into the common problem of taking too long for new hires to become effective.

Industry 287

Industry Organization Technology 287

Martin Fowler

JANUARY 18, 2024

At the turn of the century, I was lucky to involved in several projects that developed the practice of Continuous Integration. I wrote up our lessons from this work in article on my website, where it continues to be a oft-referenced resource for this important practice. Late last year a colleague contacted me to say that the article, now nearly twenty years old, was still useful, but was showing its age.

Continuous Integration 363

Continuous Integration Resources Industry Development 363

Martin Fowler

JANUARY 4, 2024

When working with a legacy system it is valuable to identify and create seams: places where we can alter the behavior of the system without editing source code. Once we've found a seam, we can use it to break dependencies to simplify testing, insert probes to gain observability, and redirect program flow to new modules as part of legacy displacement.

Testing 185

Testing Test-Driven Development System Software 185

Martin Fowler

JANUARY 2, 2024

Another year, another time to pick six favorite musical discoveries. 2023 includes ambient bluegrass, Afro-Andean funk, Northumbrian smallpipes, dancing kora, and Ukrainian folk jazz.

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137

Martin Fowler

DECEMBER 12, 2023

Throughout my career, people have compared software development to “traditional” engineering, usually in a way to scold software developers for not doing a proper job. As someone who got his degree in Electronic Engineering, this resonated with me early in my career. But this way of thinking is flawed because most people have the wrong impression of how engineering works in practice.

Software Development 145

Software Development Software Engineering Engineering Software 145

Martin Fowler

DECEMBER 11, 2023

Test-Driven Development (TDD) is a technique for building software that guides software development by writing tests. It was developed by Kent Beck in the late 1990's as part of Extreme Programming. In essence we follow three simple steps repeatedly: Write a test for the next bit of functionality you want to add. Write the functional code until the test passes.

Software Review 254

Software Review TDD Test-Driven Development Testing 254

Martin Fowler

NOVEMBER 28, 2023

Over the last year, lots of developers have incorporated LLM coding assistants into their work, finding them a useful tool. But one of the problems of these tools is that they are unreliable, often coming up with poor or outright wrong-headed suggestions.

Artificial Inteligence 229

Artificial Inteligence How To Tools Development 229

Martin Fowler

NOVEMBER 28, 2023

Over the last year, lots of developers have incorporated LLM coding assistants into their work, finding them a useful tool. But one of the problems of these tools is that they are unreliable, often coming up with poor or outright wrong-headed suggestions.

Artificial Inteligence 130

Artificial Inteligence How To Tools Development 130

Martin Fowler

NOVEMBER 24, 2023

During the last four years, my colleague Unmesh Joshi been developing a collection of patterns to help us all better understand how modern distributed systems work. We've been publishing drafts of these patterns on this site. Now these have turned into a book, published by Addison-Wesley in my signature series. As such, we've now removed the work-in-progress drafts from this site, and have replaced them with a catalog of pattern summaries.

System 200

System Development 200

Martin Fowler

NOVEMBER 7, 2023

In the second (and final) part of his explanation of React Headless Components Juntao Qiu explores how a headless component allows us to create a visually different component that does the same base behavior, and how it encourages better factoring as we extend base behavior further.

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Martin Fowler

NOVEMBER 2, 2023

It's now been a year since The Muskover, what does my use of social media look like now, both as a reader and a writer?

Media 266

Media Social 266

Martin Fowler

NOVEMBER 1, 2023

As React UI controls become more sophisticated, complex logic can get intertwined with the visual representation. This makes it hard to reason about the behavior of the component, hard to test it, and necessary to build similar components that need a different look. Juntao Qiu tackles this by using a Headless Component , which extracts all non-visual logic and state management, separating the brain of a component from its looks.

Testing 285

Testing 285

Martin Fowler

SEPTEMBER 19, 2023

How is code generation with GenAI different from more "traditional" code generators? The newest memo in Birgitta Böckeler's explorations of GenAI talks about abstraction levels in software engineering, and on which levels GenAI sits in the translation of our thoughts into zeros and ones.

Software Engineering 231

Software Engineering Engineering Software 231

Martin Fowler

AUGUST 15, 2023

Join Tim Cochran and Rickey Zachery on Thursday, September 7th 1-2pm EST for a webinar on Bottlenecks of Scaleups: Technology mistakes every growing startup makes. They researched Thoughtwork's portfolio to analyze why companies struggle to scale, spanning across Technology, People, and Product. Covering areas such as experimentation culture, overcomplicated architectures, onboarding, developer productivity, product and engineering collaboration, and cost efficiency.

Architecture 246

Architecture Culture Research Engineering 246

Martin Fowler

AUGUST 14, 2023

We are saddened today to learn of the passing of Stefan Tilkov. We’ve met Stefan several times at workshops and conferences and always enjoyed his good company and insightful views. He advocated many of the things that we and our colleagues support - and as well as skillfully explaining these ideas, he also backed them up with concrete experience from his work.

Conference 126

Conference Company 126

Martin Fowler

AUGUST 10, 2023

In her 5th memo about exploring GenAI for software development, Birgitta Böckeler answers the frequently asked question if coding assistants are making the practice of Pair Programming obsolete. Spoiler alert: They don't.

Programming 218

Programming Software Development Software Development 218

Martin Fowler

AUGUST 10, 2023

Sarah Taraporewalla moves on to the remaining two strategic directions that are part of growing the business. Expanding into new customer segments can introduce new operational processes or channels. Inorganic growth (eg acquisitions and mergers) needs an understanding of the drivers of increased value and the long term expectation (eg merge or keep separate and divest) for the business unit.

Strategy 215

Strategy 215

Martin Fowler

AUGUST 10, 2023

When scaleups need to start working on cost efficiency, our experience is that they need to form a cost optimization team to work on the immediate steps that are needed. In this installment   Sofia and Stefania describe how to understand the primary cost drivers, together with the levers to get them under control.

How To 222

How To 222

Martin Fowler

AUGUST 8, 2023

My colleague Sarah Taraporewalla describes an approach to building technology strategy that challenges the convention. It starts by identifying the overall strategic directions that the organization is considering, and using common aspects of these directions to indicate the investigations needed for the organization to understand the technology implications raised by that strategic change.

Strategy 185

Strategy Technology Organization Marketing 185

Martin Fowler

AUGUST 3, 2023

While coding assistants like Copilot can improve speed and flow, they can also disrupt it. Birgitta Böckeler looks at two ways in which they can get in the way : amplifying bad or outdated practices, and review fatigue.

Software Review 157

Software Review 157