In software engineering, as in many creative and technical fields, the environment shapes how we think and work. An intriguing psychological phenomenon known as the Cathedral Effect offers valuable insights into how physical and virtual workspaces can be designed to optimize both high-level creativity and detailed execution. What Is the Cathedral Effect? The Cathedral Effect reveals how ceiling height influences cognition and behavior. High ceilings evoke a sense of freedom and openness, fostering abstract thinking, creativity, and holistic problem-solving. In contrast, low ceilings create an enclosure that encourages focused, detail-oriented, and analytical work. Research shows that exposure to high ceilings activates brain regions associated with visuospatial exploration and abstract thought, and confirm that people in high-ceiling environments engage in broader, more creative thinking, while low ceilings prime them for concrete, detail-focused tasks Applying the Cathedral Effect to Software Engineering Software development involves both high-level architectural design and detailed coding and testing. The Cathedral Effect suggests that these phases benefit from different environments: High-level work (system architecture, brainstorming, innovation) thrives in “high ceiling” spaces- whether physical rooms with tall ceilings or metaphorical spaces that encourage free-flowing ideas and open discussion. Detailed work (analysis, programming, debugging) benefits from “low ceiling” environments that support concentration, precision, and deep focus. Matching the workspace to the task helps teams think and perform at their best. Practical Suggestions for IT Teams and Organizations Create Dedicated Physical and Virtual Spaces If possible, design your office with distinct zones: High-ceiling rooms for architects and strategists to collaborate and innovate. These spaces should be open, well-lit, and flexible. Low-ceiling or enclosed rooms for developers and analysts to focus on detailed work without distractions. For remote or hybrid teams, replicate this by: Holding open, informal video sessions and collaborative whiteboard meetings for high-level ideation. Scheduling “deep work” periods with minimal interruptions, supported by quiet virtual rooms or dedicated communication channels. Match People to Their Preferred Environments We should recognize that some team members excel at abstract thinking, while others thrive on details. Assign roles and tasks accordingly, and respect their preferred workspace to maximize productivity and job satisfaction. Facilitate Transitions Between Modes Switching between big-picture thinking and detailed work requires mental shifts. Encourage physical or virtual “room changes” to help reset focus and mindset, reducing cognitive fatigue. Foster Cross-Pollination While separation is beneficial, occasional collaboration between high-level thinkers and detail-oriented workers ensures ideas remain practical and grounded. Why This Matters Ignoring the Cathedral Effect can lead to mismatched environments that stifle creativity or undermine focus. For example, forcing detail-oriented developers into open brainstorming sessions can cause distraction and frustration. Conversely, confining architects to cramped spaces can limit innovation. By consciously designing workspaces and workflows that respect the Cathedral Effect, organizations can foster both creativity and precision, leading to better software and more engaged teams.

Quick one. Just joined the System Z Enthusiasts Discord community. They are a pretty awesome group.

Continuous availability The slide deck tells me that it was in 2006 that I created a set of slides for "Kees" with an overview of the continuous availability features of an IBM mainframe setup. The deck's content was interesting enough to share here, with some enhancements. What is availability? First, let's talk a little bit about availability. What do we mean when we talk about availability? A highly available computing setup should provide for the following: A highly available fault-tolerant infrastructure that enables applications to run continuously. Continuous operations to allow for non-disruptive backups and infrastructure and application maintenance. Disaster recovery measures that protect against unplanned outages due to disasters caused by factors that can not be controlled. Definitions Availability is the state of an application service being accessible to the end user. An outage (unavailability) is when a system is unavailable to an end user. An outage can be planned, for example, for software or hardware maintenance, or unplanned. What causes outages? A research report from Standish Group from 2005 showed the various causes of outages. Causes of outages It is interesting to see that (cyber) security was not part of this picture, while more recent research published by UpTime Intelligence shows this growing concern. More on this later. Causes of outages 2020 - 2021 - 2022 The myth of the nines The table below shows the availability figures for an IBM mainframe setup versus Unix and LAN availability. Things have changed. Unix (now: Linux) server availability has gone up. Server quality has improved, and so has software quality. Unix, however, still does not provide a capability similar to a z/OS sysplex. Such a sysplex simply beats any clustering facility by providing built-in, operating system-level availability. Availability figures for an IBM mainframe setup versus Unix and LAN At the time of writing, IBM publishes updated figures for a sysplex setup as well (see https://www.ibm.com/products/zos/parallel-sysplex): 99.99999% application availability for the footnote configuration: "... IBM Z servers must be configured in a Parallel Sysplex with z/OS 2.3 or above; GDPS data management and middleware recovery across Metro distance systems and storage and DS888X with IBM HyperSwap. Other resiliency technology and configurations may be needed." Redundant hardware The following slides show the redundant hardware of a z9 EC (Enterprise Class), the flagship mainframe of that time. The redundant hardware of a z9 EC Contrasting this with today's flagship, the z16 (source https://www.vm.ibm.com/library/presentations/z16hwov.pdf), is interesting. Since the mainframe is now mounted in a standard rack, the interesting views have moved to the rear of the apparatus. (iPDUs are the power supplies in this machine.) The redundant hardware of a z16 Redundant IO configuration A nice, highly tolerant server is insufficient for an ultimately highly available setup. Also, the IO configuration, a.k.a. storage configuration, must be highly available. A redundant SAN setup The following slide in the deck highlights how this can be achieved. Depending on your mood, what is amusing or annoying and what triggers me today are the "DASD CU" terms in…

Beautiful things are easier to use. We can also apply this to technical designs. This often surprises a non-technical audience, but techies will recognize the beauty that can be present in technical solutions. For example, symmetrical diagrams not only give a quick insight into an orderly, robust solution but are often also very appealing to the eye. Symmetrical and well-colored diagrams are easier to read and understand. Old PowerPoint presentations using the standard suggested colors were horrendously ugly, and I am sure the people using these colors did not want to be understood. (Nowadays, PowerPoint comes with more pleasing color schemes) The success of the Python programming language is not in the least its forced readability. No crazy abbreviations as in C that make code unreadable (but programmers look very smart). Beautiful code (yes, such a thing exists) is easier to read and understand. If aThen bElse If c Then d Else If e Then f… versus Case a bCase c dCase e f… It is pretty evident. But do we care about the quality and beauty of code nowadays? Throw-away software is abundant. Software systems are built with the idea to throw them out and replace them within a few years. Image by Ursus Wehrli That is the idea. But the Lindy effect tells us differently. Good programming is a profession that should be appreciated as such. Bad coding may be cheap, but only in the short run. We don’t hire a moonlighter to build our house. We employ an architect and a construction professional who can make a comfortable house that can be used for generations.

Anyone in the product chain can pull the Andon Cord to stop production when he notices that the product's quality is poor. Stopping a system when a defect is suspected originates back to Toyota. The idea is that by blocking the system, you get an immediate opportunity for improvement or find a root cause instead of letting the defect move further down the line and be unresolved. A crucial aspect of Toyota's "Andon Cord" process was that when the team leader arrived at the workstation, they thanked the team member who pulled the Cord. The incident would not be a paper report or a long-tail bureaucratic process. The problem would be immediately addressed, and the team member who pulled the cord would fix it. For software systems, this practice is beneficial as well. However, the opposite process is likely the practice we see in our drive for quick results. We don’t stop the process in case of issues. We apply a quick fix, and ‘we will resolve it later’. The person noticing an issue is regarded as a whistle-blower. Issues may get covered in this culture, leading to even more severe problems. When serious issues occur, we start a bureaucratic process that quickly becomes political, resulting in watered-down solutions and covering up the fundamental problems.

In software systems, backward compatibility is a blessing and a curse. While backward compatibility discharges users from mandatory software updates, it is also an excuse to ignore maintenance. For software vendors, omitting backward compatibility is a means to get users to buy new stuff; "enjoy our latest innovations!". 1980s software on 64-bit hardware DS Backward compatibility You can not run Windows 95 software on Windows 11. You can not Run MacOS X software on a PowerBook G4 from 2006. You can not use Java version 5 software on a Java 11 runtime. You can, however, run mainframe software compiled in 1980 for 16-bit hardware on the latest z/OS 64-bit operating system and the latest IBM Z hardware. This compatibility is one of the reasons for the success of the IBM mainframe. Backward compatibility in software has significant benefits. The most significant benefit is that you do not need to change applications with technology upgrades. This saves large amounts of effort and, thus, money for changes that bring no business benefit. The dangers of backward compatibility Backward compatibility also has very significant drawbacks: Because you do not need to fix software for technology upgrades, backward compatibility leads to laziness in maintenance. Just because it keeps running, the whole existence of the software is lost out of sight. Development teams lose the knowledge of the functionality and sometimes even the supporting business processes. Minor changes may be made haphazardly, leading to slowly increasing code complexity. Horrific additions are made to applications, using tools like screen scraping, leading to further complexity of the IT landscape. Then, significant changes are suddenly necessary, and you are in big trouble. Backward compatibility hinders innovation. Not only can you not take advantage of modern hardware capabilities, but you also get stuck with programming and interfacing paradigms of the past. You can not exploit functionality trapped inside old programs, and it is tough to integrate through modern technologies like REST APIs. The problem may be even more significant. Because you do not touch your code, other issues may appear. Over the years, you will change from source code management tools. During these transitions, code can get lost, or insight into the correct versions of programs gets lost. Also, compilers are upgraded all the time. And the specifications of the programming languages may change. Consequently, the code you have, which belongs to the programs running in your production environment, can not be compiled any longer. When changes are necessary, your code suddenly needs to catch up with all these changes. And that will make the change a lot riskier. How to avoid backward compatibility complacency? Establish a policy to recompile, test, and deploy programs every 2 or 3 years, even if the code needs no functional change. Prevent a pile of technical debt. Is that a lot of work? It does not need to be. You could automate most, if not all, of the compilation and testing process. If nothing functionally changes, modern test tools can help support this…

My proverbial neighbor asked me some time ago if he could have a zero data loss ransomware recovery solution for his IT shop. He is not a very technical guy, yet responsible for the IT in his department, and he is wise enough to go seek advice on such matters. My man next door could very well be your boss, being provoked by a salesperson from your software vendor. What is a zero data loss ransomware recovery solution? A ransomware recovery solution is a tool that provides you the ability to recovery your IT systems from the incident in which a ransomware criminal has encrypted a crucial part of your IT systems. A zero data loss solution promises to provide such a recovery without the loss of any data. The promise of zero data loss must be approached with the necessary skepticism. A zero data loss solution requires you to be able to decrypt the data that your ransomware criminal has encrypted with the keys that he offers to give you for a nice sum of money. To get these keys you have two options: Pay the criminal and hope he will send you the keys. Create the keys yourself. This would require some highly advanced algorithm, possibly using a tool based on Quantum computing technology. This is a fantasy of course. This first person to know about the practical application of such technology would be your ransomware criminal himself, and he will have applied this in his encryption tooling. So getting the keys is not an option, unless you are in the position to save up a lot of money, or find an insurer that will carry your ransomware risk. Although I expect that will come at an excruciating premium. The next best option is to recover your data from a point in time just before the event of the ransomware attack. This requires a significant investment in advanced backup technology, and complex recovery procedures, while giving you little guarantee as to what state your systems can be recovered. And, setting the expectations, will come with the loss of all data that your ransomware criminal managed to encrypt. We cannot make it more beautiful.