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Coding Culture

Technology Radar #27: Automotive SW perspective

As written before, I really like the regular updates provided by Thoughtworks in their Technology Radar. My focus is on the applicability of techniques, tools, platforms and languages for automotive software, with a further focus on embedded in-car software. Hence, I am ignoring pure web-development and machine learning/data analytics stuff which usually makes a huge portion of the whole report. Recently, its volume 27 has been published. Let’s have a look!

As usual, lets start with a dive in the “Technologies” sector and its “Adopt” perimeter. The first entry we can find is about “path-to-production mapping“. Its as familiar as it sounds – many of my readers will have heard about the Value Stream Mapping or similar process mapping approaches. Thoughtworks state by themselves that this one is so obvious, still they didnt cover it in their reports yet. Sometimes, the simple ideas are the powerful ones. I can confirm from my own experience that a value stream map laying out all the process steps and inefficiencies in an easy to digest manner is a good eye opener and can help to focus on the real problems instead of beating around the bush.

Something very interesting for all the operating systems and platform plans in Automotive is the notion of an “incremental developer platform“. The underlying observation that “teams shooting for too much of that platform vision too fast” is something I can confirm from own experience. Engineers love to develop sustainable platforms, but underestimate all the efforts required for it, and management with its impatience is further undermining platform plans. Following the book Team Topologies’ concept of a “thinnest viable platform” makes sense here. Not shooting too far in the first step, but also treating a platform product as an incremental endeavour.

Another one which strikes me is “observability in CI/CD pipelines“. With the increasing amount and complexity of CI/CD pipelines in one project, let alone a whole organization, many operational questions arise. And operations always benefit from clear data and overview. Recently, a then-student and now colleague and me designed and realized a tool which enables CI/CD monitoring for more than one repo, but for a graph of repos. I hope we can publish/open this project anytime soon.

In the platforms sector, Backstage entered the “adopt” perimeter. The project is actively developing forward, and indeed could be an interesting tool for building an internal sw engineering community.

Looking at the tools sector, I liked Hadolint for finding common issues in Dockerfiles.

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Coding Culture

Technology Radar #26: Automotive SW perspective

As written before, I really like the regular updates provided by Thoughtworks in their Technology Radar. Since the new version #26 was released a few weeks back, I found now the time to put down my notes. My focus is on the applicability of techniques, tools, platforms and languages for automotive software, with a further focus on embedded in-car software. Hence, I am ignoring pure web-development and machine learning/data analytics stuff which usually makes a huge portion of the whole report. Let’s go!

In the techniques section in the “adopt” circle we initially have “single team remote wall”. In a nutshell I think they mean having a dashboard showing the essential data, kpis and tasks for a remote development team. I think the trick here is the “single” as I assume that most remote teams have dashboards, however usually multiple ones loosely coupled. In my current team, our Scrum Master has created a great Jira dashboard showing some essential data which could give hints at the team’s performance.

The second noteworthy technique is “documentation quadrants”. Referring to documentation.divio.com/ this provides a nice taxonomy of different documentation types. This is very relatable, as I very often experience a fuzzy mixture of all those types scattered in many places. Certainly this is something I will bring to my work network’s attention.

Third, we have “rethinking remote standups”. This follows a general observation that conducting remote daily standups in the same duration and content like the were recommended in former times (e.g. the typical 15 min Scrum daily) does not provide the same amount of alignment within a development team. This is not necessarily because of the the meeting itself, but because other casual sync occasions during the day are happening less in remote setups. In the radar, its recommended to try an extension to one hour, and of course the goal is to decrease the overall meeting load by this. I am thorn on this one, as I was always a fan of crisp daily meetings, avoiding random rambling on topics concerning only parts of the team. Blocking 1 hour for everyone every day sounds like an overshoot approach.

Next there is again the “software bill of materials” topic. This is currently a huge topic in the software industry, there have been very concrete examples recently (e.g. the Log4Shell or NPM package events you probably read about). Tool support to transparently and consistently managing the used software in a bigger project is really needed. While in the web and cloud business there is a growing number of tools, in the embedded world there are only some puzzle pieces. I can currently think of some Yocto support for this, however this covers only Linux parts in usually more complex multi-os automotive ECUs.

“Transitional Architecture” sounds like a promising thing, even though the radar’s description stays a bit vague. Luckily there is an extensive article by Thoughtworks’ Martin Fowler on this approach. In my opinion, managing legacy software in complex setups is one of the key challenges in the whole software industry, even more so in automotive embedded software, which is characterized by the co-existence of decades old technologies with state of the art approaches. Formalizing the transition from on older architecture to a newer makes sense, as usually this transition is often not architecturally covered as extensively as a the target architecture. This leads to misunderstandings, hacky workarounds and other unwanted side effects to a sustainable development.

Going one circle to the outside, in the “assess” perimeter, we first find CUPID. Aimed at replacing the SOLID rules with instead a set of properties of “joyful code”, it has some interesting observations and paradigms. Currently I only skipped over it, I think this deserves more time and maybe a dedicated article. However, I can recommend to check out the well written original blogpost by Dan North.

In the “hold” perimeter we see “miscellaneous platform teams”. In contrast to “platform engineering product teams” described earlier in the radar, this is kind of a degradation form. If a platform team fails to define a clear product goal and identify its customers, usually the scope becomes (or is) very fuzzy, leading to a unclear platform system. Hence, its strongly recommended to avoid this by achieving clarity of what actually is the scope of the team.

In the platforms sector, I could only identify one relevant blip “GitLab CI/CD”. Recently I see a lot of discouragement of using Jenkins, and of course if you use already Gitlab for its other elements (code hosting, code review, issue tracking) you may as well use it for CI/CD pipelines. For sure its better integrated in the overall Gitlab experience. However its just another vendor-specific DSL, so I wonder if there will be practical standardization on the pipeline definition soon.

Looking at the “Tools” sector, I found the reference to the two code search tools Comby and Sourcegraph. Besides offering code search and browsing using abstract syntax tree analysis, they are also offering semi-semantical batch changes, enabling “large scale changes”. Comby is an open source tool, while sourcegraph is commercial. I think I will try at least one of them soon.

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Book Culture

Thoughts on “Reinventing Organizations” by Frederic Laloux

Next in my reviews of work-related books we have “Reinventing Organizations” by Frederic Laloux (the illustrated, shortened version). This is going to be short, I essentially read the book in an afternoon.

After some introductions, Laloux gives a historical overview on organizational philosophies, based on Ken Wilber. It starts at the impulsive, pure power-based via hierarchical via modern performance-oriented philosophies to postmodern pluralist ones. One interesting aspect here is, that even the two “older” ones can still be experienced today, the first one e.g. in street gangs/mafia, the second one e.g. in the church or public administration – and of course many companies.

The latter is based on empowerment, values and integrates diverse interest groups, and probably is by most considered already quite new or in many organizations “still upcoming”. However, Laloux claims that we may experience aklready now the dawn of a new, next philosophy, a integral, evolutionary one. He gives names three breakthroughs, which require but also trigger this. First, the increasing complexity of the systems organizations need to cope with, and the need for self-organized, decentral organizations to be able to cope with that. I would say that this approach “extrapolates” the empowerment by “built-in” trust and top-down-ruling-inhibiting organization forms in small, completely autonomous entities.

The second breakthrough is “wholeness” (“Ganzheit” in my German version of the book). It is based on the view that at their workplace, many people show and use only a part of their personality. This leads to loosing many valuable aspects and creates an unhealthy mental tension. Laloux gives some examples how this can be reliefed, e.g. by medition, group-reflection and new meeting-moderation methodologies.

Third, there is a breakthrough called “evolutionary purpose”. Its probably a reference what more recent publications and consultants call “VUCA”(Volatility, Uncertainty, Complex, Ambiguous). According to that perspective–which I have some doubts on, but maybe more in another blog post–the world around is is increasingly “vuca”. Traditionally, we would try to fight this vuca-ness, trying to impose existing problem-solving techniques–and ultimately fail. The other mental approach is to accept, even embrace this situation and–how Laloux phrases is–“dance with it”. Here, Laloux makes an interesting claim: “Most of us react very cynical on mission statements”. Oh yes!

The book contains some interesting food for thought, and it certainly has some relevant observations. Where my personal doubts come in: If I look at an historic scale, the four “traditional” organizational philosophies have been in place 10.000s, 1.000s, 100s and 10s of years, respectively. As I wrote, especially the last one (postmodern, integral) is still a quite new kid on the block. What does it tell us that new even a new philosophy comes up, and if we extrapolate the logarithmic timescale even more, will it be replace in a few months? Just kidding, however I wonder if Laloux’ evolutionary model is just a sub-type of e.g. the postmodern one, or really a new philosophy. And of course – what comes beyond that. Will there be an even more “advanced”, “progressive” organizational philosophy soon? Will things break apart and we go back to the wild days? I dont know…

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Book Culture

Thoughts on “How Google Tests Software”

During my recent years as Software Project Manager I learned to appreciate modern software testing beyond just a tool. In earlier blog posts I described my personal hands-on progress on the matter. Thanks to some teachers and mentors I gained knowledge in theory and practice and nowadays call myself a software testing enthusiast (which doesnt mean I am particularly good at it – I just enjoy the topic).

The Book “How Google Tests Software” from James Whittaker, Jason Arbon and Jeff Carollo is already some years old – a fact I didnt know about initially, but some aged concepts made me look into the publishing date. Also some references are not working anymore, including a link to Google’s own “Google Test Automation Conference”. However, its still a great summary on aspects of modern software testing, with a focus on organizational aspects. There is no mention of mutation testing, probabily-based testing and other testing approaches I would call “advanced”, instead there is a lot of focus on the specific roles in and around testing at Google.

In the forewords the authors’ boss Patrick Copeland introduces the term of “Engineering Productivity” and why he has chosen this as the department’s name. I find this term very appealing, especially in its connection to testing. In my domain, automotive, testing is often seen as something which slows projects down and its done in the very end after features have been completely implemented to “drive maturity”. For me, proper testing is a method to be faster after all, and doing it late is possible but is for from being efficient. The Engineering Productivity organization at Google gathers the lead on test activities, respective tooling around testing and the mentoring/training efforts to spread a testing mindset throughout the whole organization.

In the book, the saying “scarcity brings clarity” is coming up multiple times, and the authors say

The first piece of advice I give people when they ask for the keys to our success: Don’t hire too many testers.

How Google Tests Software, page 4

Googlers might be smart, but they are not plentiful. Every TEM we’ve ever hired from outside of Google makes the comment that their project is understaffed. Our response is a collective smile. We know and we’re not going to fix it. It’s through knowing your people and their skills well that a TEM can take a small team and make them perform like a larger team.

How Google Tests Software, page 188

As a young leader I dread the constant understaffing all around me. Such looks into highly regarded companies like Google make me believe its something inevitably in any fast-paced company. Being always short on good people compared to the tasks at hand must yield the most efficient use of people as possible. But how to balance this in a way which satisfies me is something I admit to not have found the key for yet.

In major parts of the book some key roles are described in detail with their relevance to testing: The (“normal”) Software Engineer (SWE), the Software Engineer in Test (SET) and the Test Engineer (TE). On page 7 the roles are summarized in a nutshell, while many many pages repeat and detail this again and again – a style I find very typical for American textbooks. In essence its clear and I assume my mentors must have either read the book years ago or used common root sources. The worksplit seems obvious to me now. SWEs are developing the code, but have to contribute automated testing on all levels to secure the functionality and quality of the system, even when no other test-focused roles are around. SETs are pushing the boundaries of test tooling, enabling new kinds or aspects of test automation wherever they can. TEs are driving testing especially in a “challenger” approach, to catch all the issues SWEs don’t see or dont want to see initially.

I already mentioned that the book doesnt go very deep into test technology. What I found very interesting is that Google separates their test activities simply by “small tests”, “medium tests” and “large tests”. According to the authors they chose to do this because other terms are overloaded and vague throughout the software industry do a degree that people are talking about different things and often didnt recognize.

On pages 40f some nowadays state-of-the-art concepts about how to include test automation into pipelines are brough up. E.g. having test code near to the functional code. Also the classification of small/medium/large tests is added with some concrete data: large tests have to run within 15 mins, small tests are required to execute in less than 100ms. This shows the enourmous compute power Google is able to leverage for their software development. Also there is a good note to quote:

Small tests lead to code quality. Medium and large tests lead to product quality.

How Google Tests Software, page 47

Only both in combination provide long-term value to a company. Having insufficient small tests strongly correlates to bad code quality which will slow down further development. Having insufficient medium and large tests (system tests) lead to many gaps in the functional and non-functional end-to-end testing, thus yielding bad product quality if there is not immense manual testing in place.

On page 48 two very basics rules for test cases are defined, which I find highly relatable: Tests have to be independent of each other so they can be executed in any order (and in parallel). Also tests must not have any persistent side effects.

Interestingly the book makes some references to a build and test execution system with sophisticated dependency graph analysis, without giving the tool’s name. Nowadays I know that they are referring to Bazel. The book must come from a time when it was not yet published.

On pages 54ff the authors describe a “test certified” program which they used to promote the testing inside Google, including some test certified levels for teams to achieve. In a very telling interview I learned a lot that even at Google the testing proponents had to overcome a lot of internal resistance.

The dream of a unified dashboard has haunted Googlers, much like it has at many other companies. Every year or so, a new effort tried to take root to build a centralized bug or project dashboard for all projects at Google.

How Google Tests Software, page 124

Its late and I want to finish this blog post, so I am closing with an inspiring quote from Joel Hynoski, answering why someone should pursue a career in test:

Test is the last frontier of engineering. We’ve solved a lot of the problems of how to develop software effectively, but we’ve still have a green field of opportunity to attack the really meaty problems of testing a product, from how to organize all the technical work that must get done to how we automate effectively, and responsively, and with agility without being too reactive. It’s the most interesting area of software engineering today, and the career opportunities are amazing. You’re not just banging on a piece of software any more, you’re testing the GPU acceleration of your HTML5 site, you’re making sure that you’re optimizing your CPU’s cores to get the best performance, and you’re ensuring that your sandbox is secure.

How Google Tests Software, page 206
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Coding Culture

Technology Radar #24: Automotive SW perspective

I am following the Thoughtworks Technology Radar since approximately five years. Since I first became aware about it (IIRC a colleague forwarded a version to me), I enjoyed its volumes as a condensed summary of current trends in the software industry. There is some bias towards cloud technology and machine learning which is out of my current professional interest, however there are enough other concepts/tools/aspects every time which make me investigate and followup to my best possibilities either at work or in my private projects. In this blog post I will try to list those parts which are roughly new and relevent from an automotive software perspective.

As usual, there are some selected topics on the top level they are presenting. Already the first one – Platform Teams Drive Speed To Market – is highly relevant. Its no secret that the automotive industry is widely moving towards in-house platforms, recent example from the news are vw.os (Volkswagen) and MBOS (Mercedes-Benz). The particular recommendation is to handle such platform activities explicitly as products, with all the implications. Only a platform with its own set of features, product vision, dedicated team and lifecycle can actually serve its purpose. A platform handled as a side-gig of an enduser product will neither serve the platform users well nor will it provide sustainable value, plus there would be a high chance of not surviving the first generation.

The second highlighted aspect – Consolidated Convenience over Best in Class – is also very relevant in the automotive SW sector. All of us love the regular discussion which code review tool is the best, and which CI tool is the newest hot shot we must adopt. Integrated workflow tools which integrate requirements/tickets to code, integration, tools and deployment such as gitlab and github (with github actions) promise so much more convenience in inter-tool integration and generally less setup hassle compared to having multiple tools each with its own authentication foo. However, there is also much higher risk of vendor lock-in. This can result in financial dead-ends and of course sooner or later lead to loss of flexibility on adopting new technology in the workflow area.

Jumping over the third highlighted topic and going straight ahead to the fourth – Discerning the Context for Architectural Coupling – this covers the architectural state of the union address. Baseline of the message here is “it depends”. Discussions with buzzwords like “monoliths” and “microservices” are seldom helpful, the real discussion needs to happen on the detailled requirements, constraints and principles.

Going deeper into the four sectors of the radar – Techniques, Tools, Platforms, Languages&Frameworks – lets start with Techniques. The new entry API expand and contract is directly an “adopt” recommendation. It means rather than breaking changes with new API versions too often its more about adding new interfaces while keeping but deprecating old ones, giving consumers a chance to adopt without breaking their usage. I can see immediate benefit of such patterns especially on highly used interfaces such as the vehicle communication interfaces. If “deprecation would be a thing (at scale)” it could relief many breaking integration challenges in the automotive domain.

In the trial circle we find Hypothesis-driven legacy renovation:

Rather than working toward a standard backlog, the team takes ownership of a measurable technical outcome and collectively establishes a set of hypotheses about the problem. They then conduct iterative, time-boxed experiments to verify or disprove each hypothesis in order of priority. The resulting workflow is optimized for reducing uncertainty rather than following a plan toward a predictable outcome.

https://www.thoughtworks.com/radar/techniques/hypothesis-driven-legacy-renovation

Sounds quite interesting. I am, too, used to handling technical stories like user stories. The given approach may indeed yield more efficient and effective collaboration on technical improvements.

Another very relatable technique is Lightweight approach to RFCs. Its something which my personal workstyle already incorporated since long time. I strive to create very fast first drafts for any task and then seeking review comments from my peers. Hence, I can absolutely understand the point of this topic and clearly recommend this. Any organization in need of collaboration and frequent alignment on concepts can benefit from a very lean set of templates encouraging early feedback rather than a culture which expects “perfect first shots”.

Team cognitive load and its linked Inverse Conway Maneuver give also very interesting food for thought. I am well aware about some teams in my environment who struggle a lot with the complexity at hand, and the organzational environment adds to that complexity significantly. The Inverse Conway Maneuver – organizing the team organization around how the proper architecture of a system looks like rather than structuring the architecture around the semi-random existing organizational structure – makes a lot of sense. It chimes well with the notion of Feature Teams and team ownership.

Remote mob programming as an extension of local mob programming, which is by itself the advancement of pair programming is certainly a recommended practice in many situations. Recently I have tried to bring teams together in “remote debug sessions” for hard inter-team nuts (=bugs) with not so great success. There is a lot of hesitance of teams to just spend some focus time together, and time difference in international setups is only one external factor. While (local) pair programming is something I think every team manager should at least try with his team a few times to see if it works out, mob programming depends an order of magnitude more mature team dynamics.

Under “hold” we can find Peer review equals pull request. The baseline here is that pull requests are only one way to conduct peer review, and as such its a very valid claim and call for further action. Looking only at fragmented changes (which 99% of PRs usually are) and reviewing that alone doesnt give context how a codebase looks overall. Full code reviews or audits certainly give great insights for potential refactoring efforts and even re-designs, besides other learnings.

The scaled agile framework SAFe is a hold and a look in the history shows it was since the beginning. Thats interesting. I am no expert in SAFe, and only know it in theory.

Separate code and pipeline ownership is really triggering me while I write this. Thats because I recently gave a presentation about the exact same thing and why both shouldnt be separated. I am wondering if that thought appeared to me myself or if I read about it the radar earlier. Nevertheless, I think anything else than keeping both together cannot really be justified from a professional sw development context (neglecting some extreme theoretical circumstances). Having that said, its not yet an established truths, and organizational structures and other opinions enforce a separation more often than I would wish for.

The tools sector doesnt offer really relevant insights this time, its all about backend intra, web dev, ML and that kindof stuff.

In the platforms sector the first thing which appears intersting is Backstage. Its a platform developed by Spotify which in essence is a simple overview on projects going on within an organization (company). It can be used to advertise cool efforts in the developer community. Something which could be worth a try. However, as a separate tool it may lack synchronizity with the actual developer activities. Integrating such a frontend into gitlab could yield some interesting dynamics, because that could leverage existing information about activitiy of projects and use data directly from the individiual projects/repos in there.

In the languages & frameworks sector again nothing relatable.

In total the new tech radar volume give me some very valuable insights and food for more thought.

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Book Coding Culture

Thoughts on Refactoring from Martin Fowler

In my series of book reviews on classics its time to take on another evergreen: Refactoring from Martin Fowler. It was already referenced a multiple times in the earlier books and now it was time.

The concept of refacoring is well-established nowadays, and I would say that only a company culture which incentivizes and motivates a spirit of constant refactoring can be a state-of-the-art software company. In my experience, this is easier said than done, especially when immense release pressure and tight resources lead to the well-known vicious circle of crunching and task forces, which never end. When one release was successfully squeezed out “somehow” and the next one is already knocking on the doors, how could anyone expect refactoring of code which actually “works” (it made it into the last release after all!!!). I had such discussions many times, and until today I dont feel strong enough in my arguments to convince senior managers in typical situations. Arguing with sustainable code and continuous improvement when the other side virtually puts the existence of the whole organization at risk is an uphill battle. But its worth fighting.

In essence when you refactor you are improving the design of the code after it has been written. […] With refactoring you can take a bad design, chaos even, and rework it into well-designed code. Each step is simple, even simplistic. You move a field from one class to another, pull some code out of a method to make into its own method, and push some code up or down a hierarchy. Yet the cumulative effect of these small changes can radically improve the design. It is the exact reverse of the normal notion of software decay.

Martin Fowler: Refactoring, page 9

I like this simple but strong definition, which underlines the cumulative effect of small improvements. Refactoring is not the same as the “grand redesign” or “from scratch” approaches which are often taken and loved, especially when the staff (developers, managers) is changed. Refactoring can achieve the same goals with either the same or a different staff.

After some introductory words Fowler goes ahead with a concrete example. He emphasizes the repetitive nature of changing something a little bit, then running an extensive unit test suite and then committing the changes to a repository. This approach is something I immediately started to exercise. For that I had to setup some of my testing scripts to work locally (they were purely in my CI before), but the effort was totally worth it. With my unit test coverage being 98% nowadays plus mutation testing in place, I dont have to worry a lot to break existing functionality while refactoring, and as a lost resort I have all the extensive API and acceptance testing in my CI before I can merge on master.

The true test for good code is how easy it can be changed.

Martin Fowler: Refactoring, page 77 (translated back to English)

This quote may be controversial among people with low exposure to professional software development (juniors, managers who gave up on programming a while ago), but for professionals in my environment its fortunately common sense. Which doesnt mean that its applied constistently, though.

If someone tells you that their code during refactoring didnt work for a few days you can be quite sure that they didnt apply refactoring as such.

Martin Fowler: Refactoring, page 79 (translated back to English)

Such reworks or redesign of larger parts of a codebase of course can and may happen, too, but I appreciate Fowler’s take on a clear separation. Especially in arguments with upper management, clear terminology can help. If refactoring can mean everything happening to a codebase except adding new functionality, its probably to vague. Restricting its meaning to pure tiny and small changes reduces risks a lot and may help to increase acceptance.

Refactoring Helps You Program Faster

Martin Fowler, Refactoring, page 82

This was and is also my personal strong belief, and I think there is enough evidence that this is a fact. I mentioned earlier sustainability, and if a well-design and maintained code base based on clean code principles and with constant refactoring exists, its the best way to get a graph like the red one below.

Source: https://frontendwebblog.wordpress.com/2020/07/07/notes-from-refactoring/ (who presumably has taken it from Martin Fowler: Refactoring, English version)

Note also the short part in the lower left corner, where poor design for a while may have more functionality than good design. Naturally, with hacky proof of concepts hitting production, you can push out some functionality “fast”, but at the cost of low efficiency later on. On pages 90f (German version) declares this the major argument in favor of refactoring – in the end its about the business value it provides, and that one can be immense.

On pages 86f Fowler discusses if one should reserve dedicated time for refactoring. I heard before of models like “every third sprint is a refactoring sprint” and of course situations where “management decided the next sprint is for refactoring to fully focus on features after that again”. Fowler argues that reserved refactoring slots shouldnt be a thing. I tend to agree with him, by stating that refactoring should be considered in day-to-day work efforts and not be a sepereate activity in contrast to “normal development work” (which it should be a part of). However, as the value of refactorings is hard to measure and aforementioned “implicit” integration into the developer workflow easily gets it ignored or watered down, some accompanying activities and events encouraging refactoring may provide benefit.

What Do I Tell My Manager? […]

Of course, many people say they are driven by quality but are more driven by schedule. In these cases I give my more controversial advice: Don’t tell!

Martin Fowler: Refactoring, page 89

Similar to Bob Martin, Fowler argues with refactoring being an essential part of professional software development, thus its not something a manager should even have the change to interfere with in particular. I agree – mature develops should just do it and get the time needed. Asking management for approval for such a core activitiy in the actual coding, that it would be weird to explicitly ask for it. Do you ask for permission to apply certain design patterns, too? Of course, when asked, management will respond and the answer in probably 80% not what you would do. Management will probably realize at some point of refactoring gets too extensive (if that is even possible), but in the end refactoring is for everyone’s best (see the graph above).

On pages 93f Fowler has some interesting input on the interaction of (feature) branches and refactorings which I didnt see before. In essence its simple: Both are working in opposite directions. If there are multiple branches living in parallel and in one of them refactoring is happening, it may make the other branches unmergable (and vice-versa). So if a company or project wants to encourage refactoring, it should avoid active branches wherever possible.

There are more arguments for refactoring and a myriad of hints and tricks how to apply it, when to apply it and how to carry it out in an optimal way. The second part of the book contains detailled descriptions of all types of refactorings. I have skipped through them, but I know I wouldnt remember them exactly anyways. However, with the gist of things in mind I did a major refactoring of my current pet project, and it was really fun and productive. Now my codebase is even cleaner (I did already a few rounds after reading Clean Code) and I am looking forward repeat it while I continue adding functionality.

It was a very good book and a certain recommend, if you didnt read it already.

Kategorien
Book Coding Culture

Thoughts on Clean Agile from Robert C. Martin

My third book review leads me to the third book in a row from Robert C. Martin. You may think I am a fanboy or such, but its just that as written before all those books and more I got provided from my employer, and somehow I liked the flow of Martin’s books, so I read them one after the other. But fear not, the next book will be from another author.

So “Clean Agile”: Already the title is a bit triggering. I remember a online talk from another big agile representative (forget the name though) who was very clearly discouraging to use “Agile” as a noun for anything, but always use it in its grammatically correct way as an adjective. Thats what I thought about when holding the book in my hand. However, I dont really care for the difference. Grammar is the one side, the other is that agile/agility has been a standing term in the sw industry for a while now, so one may as well use it in its noun form. Nevermind.

The first thing noteworthy is the history lesson about the waterfall process. According to Martin, the 1970 paper from Winston Royce which according to popular belief introduced waterfall and initiated its establishment, was actually arguing against this model. If that is true, a lot of people must have read only the first part of that paper and then went on implementing that part – because it chimed well with the notions of Scientific Management which were cool back then.

Martin is also very explicit about the small vs big team problem. In his opinion the organization of big teams is a solved problem since ages. What was open was the organization of small teams developing software. To scale from there seems to be the easy part for him. In theory, he may be right, but looking at my project which we scaled from 1 to 65 teams in years working on one product, the organism and interactions between teams and the overall organization cannot be reduced that easily. That would assume an organizational maturity on project level and on each single team that is hard to reach under realistic circumstances. I am not saying its not feasible, just that its not that simple. But Martin has shown to simplify a lot to make his points.

Another new information for me was the term “Iron Cross” of project management:

The reason that these techniques fail so spectacularly is that the managers who use them do not understand the fundamental physics of software projects. This physics constrains all projects to obey an unassailable trade-off called the Iron Cross of project management. Good, fast, cheap, done: Pick any three you like. You can’t have the fourth.

Robert C. Martin, Clean Agile, page 15

I agree with this assessment (of course in a theoretic setup you may be able to achieve all four, but in this world this is unlikely). On the following pages, Martin describes quite typical project development in the waterfall world up until the deatch march phase.

Another example of Martin’s provocations is his statements that “The loss of hope is a major goal of Agile.” Sounds crazy, right? What he aims at by using the metrics (like velocity) in a proper way, arbitrary and unrealistic deadlines, which are based on hopes, can be overcome, and gradually more realistic estimates can come out. This is also were he makes this statement:

Some folks think that Agile is about going fast. It’s not. It’s never been about going fast. Agile is about knowing, as early as possible, just how screwed we are.

Robert C. Martin, Clean Agile, page 27

Some pages later, Martin once again talks about the “grand redesign” – the typical “cure” when a software organisation has maneuvered itself into a dead end. He repeats his example from his earlier books, where a Tiger Team to redesign the software from scratch is caugth between having to catch up with the legacy software’s development while generating no income.

On page 50 Martin makes a memorable insight:

Humans make things better with time. Painters improve their paintings, songwriters improve their songs, and homeowners improve their homes. The same should be true for software. The older the software system is, the better it should be.

Robert C. Martin, Clean Agile, page 50

I really liked this statement. Software is in many cases connotated with the stance that old software/code bases are mostly getting worse, seldom better. Of course we all know good cases, mostly Open Source projects going on since decades (Linux Kernel, gcc, Latex, …), but in the proprietary software industry its often different. I cannot count how often old software really got worse over time – no matter if it was disimproved by rushed hacks or not changed at all. Martin is stating the obvious, but in that clarity I never saw that.

Many people have claimed that up-front planning is not part of Agile development. […] Of course the business needs a plan. Of course that plan must include schedule and cost. And, of course that plan should be as accurate and precise as practical. […]

In short, we cannot agree to deliver fixed scopes on hard dates. Either the scopes or the dates must be soft.

Robert C. Martin, Clean Agile, page 57f

I like this statement, because in few sentences Martin clarifies a typical debate around agile approaches. Some nitpickers – often with the aim to show the unsuitability of agile practices for tough industry business – claim that agile is anti plans or discourages plans.

Rising Velocity

If we see a positive slope, it likely does not mean that the team is actually going faster. Rather, it probably means that the project manager is putting pressure on the team to go faster. As that pressure builds, the team will unconsciously shift the value of their estimates to make it appear that they are going faster.

This is simple inflation. The points are a currency, and the team is devaluing them under external pressure. Come back to thatteam next year, and they’ll be getting millions of points done per iteration. The lesson here is that velocity is a measurement not an objective. It’s control theory 101: don’t put pressure on the thing you are measuring. […]

One way to avoid inflation is to constantly compare story estimates back to the original Golden Story, the standard against which other stories will be measured. Remember that Login was our original Golden Story, and it was estimated as 3. If a new story such as Fix Spelling Error in Menu Item has an estimate of 10, you know that some inflationary force is at work.

Robert C. Martin, Clean Agile, page 81

This is a very important observation and I can confirm it from practice. As a project manager I am monitoring team’s velocity charts. However, I am not doing this to enforce rising velocity charts, but to identify trends in underachievements (commitment vs achievements). Speaking about the average mature team, I think the best to aim for is a stable sprint velocity over longer duration of times, leading to a sustainable pace (Martin writes more on that on page 103). The last paragraph above gives a nice approach how to determine velocity inflation.

Working overtime is not a way to show your dedication to your employer. What it shows is that you are a bad planner, that you agree to deadlines to which you shouldn’t agree, that you make promises you shouldn’t make, that you are a manipulable laborer and not a professional.

This is not to say that all overtime is bad, nor that you should never work overtime. There are extenuating circumstances for which the only option is to work overtime. But they should be extremely rare. And you must be very aware that the cost of that overtime will likely be greater than the time you save on the schedule.

Robert C. Martin, Clean Agile, page 103

I really like this quote, it fits to my “natural instincts”. My work and contributions are most sustainable when I can work more or less normal hours. That means I can rest, stay sane and – more relevant to my employer – reflect on what is going on at work. As a team and project manager my day at work is usually crammed with meetings, mails and nagging people. Very rarely I have time to think deeply about what goes on. Hence, the best ideas I have after work, during weekends and vacations. I usually make sure to take notes about those ideas, so I can followup during working times.

On pages 106f Martin shares another interesting anecdote about the “developer hierarchy” at a printer company. The baseline is, that the printer software developers enjoyed a lot of praise for their direct contributions to the company’s main business. However, that led to elitism and closing up of their code. Other software developer working in indirect matters did receive lower trust and couldnt contribute that much. I think this is something to observe also around my work. The ones directly developing fancy features which make it on magazines and news pages feel much more appreciated than the ones working in the machine room, keeping the whole machinery running. I think the boundaries between those groups must be as permissive as possible.

The point is that Continuous Integration only works if you integrate continuously.

Robert C. Martin, Clean Agile, page 108

Simple but powerful words. I cannot believe how often CI is preached and promised, while it boils down to integration of a full team’s work once a sprint or even less.

The continuous build should never break. A broken build is a Stop the Presses event. I want sirens going off. I want a big red light spinning in the CEO’s office. A broken build is a Big Effing Deal. I want all the programmers to stop what they are doing and rally around the build to get it passing again. The mantra of the team must be The Build Never Breaks.

The Cost of Cheating

There have been teams who, under the pressure of a deadline, have allowed the continuous build to remain in a failed state. This is a suicidal move. What happens is that everyone gets tired of the continuous barrage of failure emails from the continuous build server, so they remove the failing tests with the promise that they’ll go back and fix them “later.”

Robert C. Martin, Clean Agile, page 109

Not much more to say, except that this is hard in traditional environments to achieve, and very easy to loose once gained. Just recently I got the chance to focus more, which I really appreciate.

The belief that quality and discipline increase speed is a courageous belief because it will constantly be challenged by powerful but naive folks who are in a hurry.

Robert C. Martin, Clean Agile, page 134

I love that quote because it is just true. And I admit that sometimes I am one of those naive folks. However I work to be it less every day.

Towards the end of the book, Martin lays out the new movement of Software Craftmanship. I frankly didnt hear about it before, but I like the ideas about it.

As aspiring Software Craftsmen we are raising the bar of professional software development by practicing it and helping others learn the craft. Through this work we have come to value:

Not only working software, but also well-crafted software

Not only responding to change, but also steadily adding value

Not only individuals and interactions, but also a community of professionals

Not only customer collaboration, but also productive partnerships

That is, in pursuit of the items on the left we have found the items on the right to be indispensable.

https://manifesto.softwarecraftsmanship.org/

Many will recall the format following the Agile Manifesto. However I see it a very valuable extension from the perspective of developers.

Let me end here. Probably long enough text for anyone ever to read here 🙂

Kategorien
Culture

How some distrust in modern software development is good

A few weeks ago a colleage mentioned in an argument that in contrast to open source communities, where mutual distrust between many personally unknown contributors is prevalent, in a corporate environment due to the contracts of all developers trust can be assumed. Therefore, some specific – but out-of-scope of this article – practices cannot be taken over to corporate environments. It made me think.

I concluded today that there has to be a differentiation. One has to distinct between trust in people and trust in code/results.

It may be true or not true, that in corporate environments there is more trust, because many contributors know each other personally from regular meetings, sitting next to each other in an office and, maybe most influencial, by the nature of their contracts. Of course we all are also aware of the sources of corporate distrust, mainly politics and personal agendas. One could also argue that in Open Source projects there is more trust among contributors because of the mutual mindset, nice conferences and legends of old mailing list battles against each other or united against some guys from the other paradigm (indentation anyone?). I would say its in every organization’s highest interest, to nurture and foster trust among the developers, most importantly trust in the fact that all are doing the best they can with best intentions. An organization in which people think others are intentionally blocking or even destroying their progress is toxic and will lead to significant problems sooner or later (or needs to be covered with effort, money, time, …).

My point is that trust in code is never good. Its a bold statement, but look at your own environment. Are you 100% trusting the code you work with? I would not. Do you trust the Pull Request from someone without looking at it? I would not. Do you trust your own code you have produced today? Yeah maybe, but when you look at it in one year you should have at least a critical perspective. Some genius developers think their code is always perfect (and it may very often be). I dont think it is. There is also strong evidence that thinking your code is perfect doesnt make you a good developer. A good developer knows about the dangers coming with every written line of code. Almost every code can be source for trouble. It can contain bugs, it may call other code which is buggy. Even if its absolutely bug-free today, tomorrow a compiler issue, weird build pipeline or hardware glitches may break it (and rather than solving the root cause you may be forced to update your code with a nasty workaround). Some may say that viewpoint is depressing, and it is a bit. But neglecting the facts is not sustainable. It is the daily struggle of our industry.

Coming back to my colleague’s argument I would say: In our corporate project we have about the same amount of trust among team members like in an open source community of comparible size and we work hard every day to improve the basis for trustful collaboration. But we should also be always distrustful with the code we produce ourselves and the code we get from external parties.

And there is and should be no difference between open source projects and corporate environments regarding trust in people and distrust in code.

Looking forward to get your comments on this.

(I posted this article also on LinkedIn)