Udi Dahan   Udi Dahan – The Software Simplist
Enterprise Development Expert & SOA Specialist
 
   
    Blog Consulting Training Articles Speaking About
  

Archive for the ‘The Team’ Category



#NoEstimates – Really?

Saturday, April 19th, 2014

estimatesThere has been some discussion online recently about the issue of estimates in software development, specifically under a meme called #NoEstimates.

This came up when I was in London for the DevWeek conference at the speaker dinner with Austin Bingham, Rob Smallshire, and Allen Holub and I wanted to share some of the ideas that came up, as well as some of my personal opinions on the matter.

Context matters

When you’re in an organization that is continuously developing and evolving a product, platform, or suite, your context is quite different than when you’re working on a project either for an external client or an internal one.

In short: product vs. project.

While in both contexts you’ll want frequent releases, the main difference is that a project is meant to achieve a certain state of “done-ness” in a bound period of time. A product is not ever meant to be “done” in that way. A successful product is one that continues to evolve over time, with that success (arguably) resulting in more resources being dedicated to its development.

If we were to zoom out our scope beyond that of the project, we’d probably see certain product-ish qualities at the level of a client’s entire IT environment – no state of “done-ness” and similar consequences of success.

Where estimates are needed

Whether you’re in a product development organization or the CIO of an enterprise, there are a certain number of features/projects (FP) that people in “the business” want done. Let’s assume that each FP has a certain amount of business value that its implementation would result in and that that value is known in advance.

Sidebar: Clearly, the business value of any feature or project can not be known with much certainty in advance of it being implemented. Still, for the purpose of keeping the analysis simple for now, let’s table this issue for a bit.

While you might think it’s reasonable to perform the work on these FPs in order of decreasing value, that is mistaking revenue for profit/return-on-investment (ROI).

In other words, we need to know roughly how much each of them costs to be able to calculate its predicted ROI (value – cost).

Only then can we decide in which order to do the work.

So, we need somebody technical to give an estimate.

High-level estimates

In this context, sometimes it’s enough to provide 3-4 buckets describing the amount of work – I like the approach of using shirt sizes: S, M, L, XL.

This can help the organization decide quickly to charter the development of the FPs with very high value and very low cost. These low hanging fruit are great for getting started, but when you’re done with them, then you have to decide between a bunch of FPs whose predicted ROI are all very close to each other.

Before doing that (!), it’s important that no projects with an XL size are fully chartered as is – no matter what the value.

When a technical person gives an XL estimate, that means “this is so big, I really have no idea how long it’ll take”. The variance can be huge here – in some cases, they might not even be certain if the request is doable without being given some time to do additional research first. And that is exactly why you need to carve out a certain chunk of time and resources for doing that research.

“But you don’t understand, Udi! We need this done ASAP.”

Believe me when I say that that ship has already sailed.

There’s a pretty good chance that before that extra-large FP is half-done, so much time will have gone by that business priorities will have shifted. Unfortunately, by that time so many resources will have been invested in it that nobody will have the guts (or political capital) to pull the plug on it. The best people will start leaving – sometimes to other FPs but, more often, the company as well. Even when these nightmarishly large missions are eventually done – they end up being something of a Pyrrhic victory.

So, what to do?

Well, beyond financing a certain amount of directed and scoped research and development to get a better handle on that beast, let me suggest this:

Enter the “Lean Startup”

If you haven’t heard about it yet, and regardless of whether you’re actually working at a startup (I’d say that it is even more important for large organization), you need to check out the Lean Startup.

While I won’t be able to do justice to it here, let me use this admittedly gross oversimplification:

You are mistaken about the predicted business value.

Really.

So what you need to do is to start applying the scientific method – a series of experiments in which you are looking for proof to validate your hypothesis about the predicted value, where the outcome of one experiment is used to formulate another hypothesis to be tested in the next experiment.

Let me say this differently – until you are as rigorous in evaluating the predicted value of a given initiative as you are in estimating its cost, with that rigor increasing with the size of the initiative, you have no business starting to work on it.

And this is what’s missing from most of the software development world.

Portfolio management

I don’t really care what you call it, but the portfolio of potential investments and the risk analysis around them needs to be handled properly.

Based on the language I’ve chosen, you can see parallels to the world of finance. Now, before your mind starts going to the news of all the shady crap that’s been going on in the world of finance, understand that there are both positive and negative outliers in every domain.

That being said, I won’t point you to books on finance (at least, not for starters).

I suggest reading Manage your project portfolio, by Johanna Rothman (one of my favorite people in the world). She also has a couple of blogs, and that can help you get started.

This has already gotten quite long, so I’ll skip a bit and talk about what you should do if you’re “just” a developer being asked to give an estimate.

How to give a good fine-grained estimate

Here’s the format to use:

This will take a team of N between T1 and T2 and I am P% confident in that range, with the following assumptions (1, 2, 3), and most importantly, that the team does not work on anything else during that period of time.

Let me repeat that important bit again:

Assuming the team does not work on anything else.

Most of the kinds of people who ask for estimates aren’t going to like that kind of answer. You may get some pushback, “don’t be clever – can this be done by the end of the year, or not?”. In other words, they’re asking you for a commitment – not an estimate. This is common with certain types of dysfunctional organizations – the project management people are only measured on adherence to schedule, not on whether the system solves the right problem. You, the developer, want to make sure you’re solving the right problem – you want to be Agile. But that’s not the point.

Let me repeat – Agile is not the point.

If the organization around you is dysfunctional, be smart – don’t try to be right. Solving the right business problem is the right thing to do, but often it’s not smart thing to do. If you don’t like having to deal with this kind of organizational politics, you had better find yourself a different organization – otherwise, you had better be smart.

How to receive good estimates

Assuming you’re a team lead, project manager, product owner, or something similar, here’s how to respond when someone gives you an estimate in the above format.

  1. If P is subjectively high enough and T2 is subjectively low enough, give them the green light.
  2. If P isn’t high enough, or the range of T1 to T2 is too broad:

    1. If you have previously given them time to do research (RT), double the value of RT.
    2. Make sure they are only doing research during this time (no other development).
    3. The purpose of the research is to increase P, or decrease the range of T1-T2
    4. When receiving the new estimate, go back to the beginning.

To be clear, “research” does not mean navel-gazing. It can and often will involve writing a bunch of code as well as on figuring out what the requirements should have been in the first place.

“But Udi, won’t this end up wasting time that could be better used on actually building the system?”

No.

In reality, this will end up paying back all the time that should have been spent up-stream on portfolio management and requirements analysis activities.

Which brings me to…

Working software over comprehensive documentation

Sometimes, writing high-quality working software is the last thing you want to do.
Specifically, the earlier you are in the project, the less likely that you should be focusing on code.

Often, the most cost-effective thing to do is some rapid-prototyping like creating UI mock-ups to verify what the system should really do.

This really deserves a blog post of its own (with thanks to Geert for finding the link), but suffice it to say that this is a skill-set all its own that should exist in every software development organization.

On other word on small startups – I often hear from people who are doing their own startup that want to do DDD, CQRS, SOA, and a bunch of other three-letter-acronyms they picked up on various blogs and books, because this time it’s up to them; this time they’re going to do it right.

No, no, no – stop that. Go read the Lean Startup. Then do it. And if you’re extremely lucky, you will be so successful that in a couple of years you will be in the position to rewrite the system – the only difference is that now you’ll REALLY know what the system is supposed to be.

In closing

OK – so that’s well over 1500 words I’ve spilled on the topic.

While the hashtag #NoEstimates makes a great soundbite, estimates are an important part of the information that needs to flow around the organization to help quantify and mitigate risk. Too often there are various organizational dysfunctions tangled up in the same areas as estimates which, I suppose, could give the impression that the estimates are to blame.

While I wish I could tell you that all you need to do is find an organization that doesn’t have any of these dysfunctions and all will be well for you, unfortunately there aren’t any organizations without them. Just like all families are dysfunctional in one way or another, so too are organizations. This is simply because each of us human beings is somewhat dysfunctional.

Well functioning organizations are made up of highly aware individuals – people who have become able to see and mitigate some of their personal issues, and thus can be patient as the people around them similarly work through their issues. Together, these individuals continuously create and adapt their working processes and systems to compensate for the various dysfunctions in the group.

Under these iteratively growing conditions of mutual trust, various kinds of estimates are performed at different levels and times and are just a normal part of communication and decision-making.

Please, don’t throw out the baby with the bath-water.



Thoughts on a career in software development

Friday, December 27th, 2013

helping_handFor much of the history of computers, programmers really only had one path to take – upward into management.

While you could go from Junior Programmer to Senior Programmer, sooner or later you were faced with the choice of becoming a Team Lead or having your career stagnate.

The primary difficult with becoming a team lead is that the skills that made you an excellent Senior Programmer didn’t really carry over to leading a team.

On leading teams

Much ink has been spilled (and keyboards been pounded) on this topic, so I’ll just give the common solution that is proposed to this issue – having a parallel technical career track to the traditional management track.

After being a senior programmer, developers can grow into architects and upwards. IBM, for example, has the title “Fellow” reserved for this ultimate level.

An IBM Fellow is an appointed position at IBM made by IBM’s CEO. Typically only 4 to 9 IBM Fellows are appointed each year in May or June. It is the highest honor a scientist, engineer, or programmer at IBM can achieve. —Wikipedia

All that’s well and good, but I have a feeling that something is still missing.

Why does it have to be either/or?

What if we allowed, nay – encouraged, developers to try both types of roles as they advance in their career?

After your first year as a senior programmer, you are then assigned to be a mentor to a junior programmer. You don’t assign them work, but take responsibility for some of their professional development. During this time, you also start learning what it takes to be a good team lead and developing your soft skills – yourself being mentored by a more senior team lead (probably not a good idea for it to be the team lead on the project you’re working on). From there, you take on a team lead role on a small-ish project leading 2-3 other developers.

During your time as a team lead, architects in the company work with you to deepen your technical knowledge of larger system concerns – grooming you for your next role: an architect. Your experience as a team lead gives you new found appreciation for managing technical risk.

Later, as an architect with developed soft-skills, you are now much more capable of getting teams to adopt your ideas and to want to do “the right thing”, rather than just deliver the project any way they know how. Even as you develop your expertise in various technological areas, the organization has an eye on bringing you back to being a team lead, this time on a larger project.

In praise of the zigzag

I think this has actually been happening more than just a little in our industry, although I believe it usually happens as people move from one company to another.

Is it possible that the limitations of the structures in their previous companies contributed to their choice to move to another company? Well, I wouldn’t discount it.

I don’t think companies should pigeonhole developers – either you’re an X or a Y.

Human beings thrive on variety and occasionally stretching out of their comfort zone.

I believe this model optimizes for people’s personal growth and can be tuned quite easily.

I think this is also very much in alignment with the Software Craftsmanship movement and can make it easier for companies to develop and hold on to the talent they’ve been lucky enough to hire in the first place.

In closing

While I believe this model is workable for a lot of the software industry, both for consulting companies and internal development organization, it’s clearly not going to be applicable for small startups. That being said, if the startup is successful and starts growing, it might not be such a bad idea to lay the groundwork for the team early on.

I don’t claim that this is the “best model” out there, and I haven’t tried it myself (yet), but I do believe that it has potential and would love to (re)spark the conversation about processes and structure that has seemed to die down under the Agile maxim of “Individuals and interactions over processes and tools” (though I believe that Agile as a whole *has* gotten us pointed in a better direction than where the industry was before).

What are your thoughts?

Write a comment or, even better, write something on your blog and spread the word!



On Mookid joining NServiceBus, and what that means for Rebus

Wednesday, September 11th, 2013

mogensWhile I don’t generally blog about it when we hire people here at
Particular Software (as we’ve been roughly doubling our size each year), this situation is slightly different.

Mogens Heller Grabe, creator of Rebus, will be joining us.

The advantages to the NServiceBus community are pretty clear – having more people in the core team with experience building service bus technology will help us get more done, faster.

What I want to talk about is the impact to the larger open-source ecosystem.

On Open Source

Although NServiceBus moved away from the permissive Apache license some time ago, the source is still and will continue to be available under the OSI approved Reciprocal Public License.

Rebus has always been licensed under the permissive Apache license and, as far as I know, will continue that way.

In order to make sure that the Rebus code base is in no way tainted and ensure that its users remain protected, Mogens will not be able to continue contributing code to Rebus. To hear Mogens comments on this change, see his blog post on the topic.

So you’re killing Rebus?!

That question always come up whenever some company hires someone whose working on an open-source project, doesn’t it? I can only speak for NServiceBus here, but our focus is on getting additional talent – growing the team, so that we can achieve all the great things we’ve got planned, not on killing anything.

I don’t think we could “kill” Rebus even if we wanted to. There is a thriving community of users and committers around Rebus who have the choice and ability to keep it going (or not).

And there isn’t really anything that we could gain commercially from the death of Rebus – its users probably wouldn’t switch to NServiceBus anyway. If anything, they’d most likely go with one of the other free, open source service buses out there – most notably, Mass Transit.

So, it’s just business as usual then

Pretty much.

We’re going to continue hiring more people to help realize our vision of the Particular Service Platform, as well as partnering with companies that help complement this vision (like we’ve done in the past with RavenDB).

And if you’re either an independent consultant or working at a consulting company and have experience delivering NServiceBus projects, we have an interesting proposal for you, so please contact us.

Exciting things are coming.



The right methodology for your project

Sunday, August 4th, 2013

certified_agileIn this day and age where “Agile” is kind of the default in many organizations, I thought I’d point this out:

I’m on record that every project needs its own methodology; further, that for most projects, the beginning, middle, and end are different enough to need their own; further, that every team ought to reexamine, alter and experiment every month.
Alistair Cockburn – one of the authors of the Agile Manifesto1, 2

Allow me to say that again:

Every project needs its own methodology

And that that methodology should not be statically adhered to – instead you should expect to adjust that methodology monthly, to the level that an external observer seeing the middle of your project would identify that you are, in fact, using a different methodology than the one you were using at the beginning of the project. And the same would go for the end of the project.

And if you don’t know Alistair yet, let me tell you – he really knows what he’s talking about.

Read more of Alistair’s work.



Leveraging irrationality towards success

Thursday, September 27th, 2012

irrationalWe’ve all seen good ideas emerge in the software space – from objects, to components, to services, to domain models, and the *DD approaches. Yet, in most organizations, it is very hard for these ideas to get traction.

I’ve heard from countless developers and architects over the years about their frustration in getting everybody else to go along with them. “Can’t they see how much better [new approach] is over what we’re doing now?!” they ask, believing that things could and actually would be evaluated on their merits, especially in a rational field like IT.

The usual explanation I give has a couple of parts.

Conway’s Law

In 1968 Melvin Conway penned what later became known as Conway’s Law which stated:

“organizations which design systems … are constrained to produce designs which are copies of the communication structures of these organizations.”

An important corollary of that law is that if you wish to have a significant impact on the design of a system, you would need to have a similarly significant impact on the communication structure of the organization making that system.

The main problem is that the people that tend to be pushing for DDD, IoC, CQRS, SOA, etc are usually not as strong when it comes to the soft skills that are so necessary for bringing about organizational change. The thing is that, at a minimum, these types of changes take 3 to 5 years so it really takes a long-term commitment, both from the individual and the organization.

On the rationality of people in IT

First of all, people are a whole lot less rational than they’d like to believe – or that they’d like other people to notice. In fact, people will go to great lengths to maintain the appearance of consistency and rationality, even at the cost of harm to themselves. How’s that for irrational?

Don’t take my word for it – there’s a great book on the topic: Predictably Irrational: The Hidden Forces That Shape Our Decisions. The somewhat scary thing about it is that not only are we irrational beings, but that that irrationality can be predicted and, yes, even manipulated.

Once you can understand that the people you’re trying to convince aren’t Vulcan, you have a much better chance of being effective. I’d say that, for myself, understanding my own modes of irrationality increased my effectiveness as well, and made me quite a bit happier in life too.

Why you need to bring in a consultant

This isn’t me hawking my wares – believe me, I’m busy enough as it is, but let me know when this starts to sound familiar to you.

There’s a problem in your organization – could be that you’re not delivering software fast enough, high enough quality, whatever. Suffice it to say that Management isn’t happy. You’ve been living this pain for a while and know exactly what the source of the problem is (more often than not, management has at least a hand if not a whole arm in it). You come up with some recommendations, bring them to the higher-ups, but ultimately are ignored, dismissed, or don’t even get into the room.

Some time later, management brings in a Consultant (that’s right, with a capital ‘C’) who is there to figure out what’s wrong and come up with recommendations. In some cases, especially in larger organizations, they bring in a whole bunch of them from a brand name like McKinsey or Ernst & Young.

If these guys are smart, they listen to you, ultimately presenting your analysis and recommendations to management. Of course, those higher-ups are in awe of how quickly these guys were able to understand the inner workings of their organization. That awe lends instant credibility to their recommendations which are then adopted and given powerful political backing.

And you’re sitting there thinking, “but… but… but that’s what I was saying!!”.

It’s not the message – it’s the messenger.

Let me put it another way, explained from the perspective of management – we’re having problems, you work here, ergo you’re part of the problem. Also, you don’t make that much money (compared to management), so how smart could you be? Those brand-name consultants, well, they cost a LOT, so they MUST be good (good enough to know not to work here too).

Therefore the more the consultant costs, the more likely management is to listen, which ultimately creates the conditions for success, which makes the change happen, which proves to management that they were right to bring in an expensive consultant. A vicious (or virtuous) cycle – depending on how you look at it.

Now, it doesn’t always work this way, but it does often enough to perpetuate management’s world view.

In Closing

I do hope your organization and its leaders aren’t trapped in this kind of dysfunction, but if they are, know that you’re not alone and that you can get help – either via consulting or in some books:

Some good books include Made to Stick: Why Some Ideas Survive and Others Die and the grandfather of the field: How to Win Friends & Influence People. There are countless others and there isn’t any right place to start – the most important thing to do is to start.

It’s been over 40 years since Melvin Conway’s observation and, as an industry, we’re still relearning these things – usually through the school of hard knocks. But there is an upside here – I’m pretty sure that, knowing these patterns, you could pick up on some signals during the interviewing process and find a company that’s outgrown many of these issues – one that would be able to have more meritocratic discussions on technical choices.

In the worst case, you could become a consultant and make a living off of all this irrationality :-)



Change is hard

Sunday, January 8th, 2012

diamondOrganizational change is hard – like the way a diamond is hard.

So, don’t try to change the organization. It’s too big anyway.
Instead, focus on changing one person at a time – that’s hard enough.

Don’t necessarily take the “one person as a time” too literally, though.
You don’t need to completely and utterly have one person won over before starting on the next.

Understand that for someone to change, that may require them admitting (either implicitly or explicitly) that the way they were doing things before was wrong. In some organizations, this can be suicide. Even if it isn’t, psychologically speaking, there are a huge number of barriers to overcome.

So, if at all possible, massage the situation in such a way that it’ll sound like they were right all along, and no-one really understood. It’s easy for someone to play along with the “misunderstood genius” story.

Next time – how to do just that.

Stay tuned.



High Availability Presentation

Monday, June 21st, 2010

OK – this is the last one, I promise. Well, for now, anyway.

Earlier this month at TechEd North America I gave a fairly new presentation that was only delivered once before (at the Connected Systems User Group in London) and I’m happy to say is now online for your viewing pleasure.

High Availability – A Contrarian View

Comments? Thoughts? Let me know.



On Design for Testability

Sunday, April 18th, 2010

keeping balanceAlmost at every conference, event, training, or consulting engagement someone asks for my opinion on the whole design for testability thing. I’m not quite sure why I haven’t blogged on this topic, especially at the time that a lot of the other bloggers were weighing in, but better late than never.

Before getting into that, I want to start with a slightly broader scope of discussion.

You see, I get asked about “best practices” on all sorts of things. And I try not to be the kind of consultant that responds with “it depends”, but the context of the question often makes the answer irrelevant. And the unspoken context of a best-practice question is:

Given infinite time and budget

The biggest problem that I see with well-intentioned, best-practices-following developers and architects is that they don’t ask the question “is this the right thing for us to be focusing on right now?” Understandably, that is a difficult question to answer – but it needs to be asked, since you don’t have infinite time or budget to do everything according to best practices (assuming those even exist).

About testing

The biggest issue I have with the “design for testability” topic is the extremely narrow view it takes of the word “testability”, usually in the form of more code written by a developer which invokes the production code of the system, also known as “unit tests”.

There are many different kinds of testing – unit, integration, functional, load, performance, exploratory, etc… where some may be automated and others not. Should we not discuss what “design for testability” means for not-just-unit-testing?

And what’s the point of testing anyway?

It’s not to find bugs.

Research has shown that testing (of all kinds) is not the most effective way of finding bugs. I don’t have the reference handy but I’m pretty sure that it’s from Alistair Cockburn’s work. Code reviews are (on average) about 60% more effective.

Don’t get me wrong – testing can provide indications that the software has bugs in it, but not necessarily where in the code those bugs are.

The purpose of testing is to provide quantitative and qualitative information about the system that can help various stakeholders in their decision-making processes. The relevance of that information indicates the quality of the testing. Here are some examples:

  • The system supports 100 concurrent users, with the expected user-type distribution (X% role A, Y% role B, etc), performing expected use-case distributions, and collaboration scenarios.
  • Time to proficiency for new users in role A is expected to be 3 days
  • Alternate #2 of use case #12 fails on step #3

As you can see, the relevance of the above information is dependent on what decisions the various stakeholders need to make. The bullet on load can help us decide if more machines are needed or if developers need to tune the performance of the systems. The bullet on time to proficiency can help us decide if larger investment in usability is required. Information like the last bullet can be used in conjunction with the first two to decide on the timing and type of a release.

The timeliness of this relevant information is critical to the success of a project.

Choosing which and how much of the various testing activities to perform when is something that needs to be revisited several times throughout the lifetime of a project, taking into account the current risks (threats and probabilities) and time and resource investment to mitigate them.

Let me reiterate – we’re not going to have enough time to do everything.

On iterations

If the only part of your organization that is doing iterations are your developers, you’re not agile.

In order to capitalize on the information that testers are providing, you need them in your iterations.

The same goes for the other roles involved in the project – business analysts, DBAs, sysadmins, etc.

I know that 99% of organizations aren’t structured in a way to do this.

I never said doing this would be easy.

On design

Figuring out what kind of design and how much to do when is just as important, and just as hard. Design for testability is one part of that, but not the only one, or necessarily the most important one at any point of time.

Within that design for testability topic is the “design for unit-testing” sub-topic which seems to be the popular one. Before getting into the design aspects of it, let’s take a closer look at the unit-testing side of things.

On unit-testing

The assumption is that having more unit tests will lead to a code-base with less bugs, thus requiring shorter time to get the system into production, which will pay back the time it took to write those unit tests to begin with.

In practice, what tends to happen is that as development progresses, testing code breaks as the structure of the production code changes. Now one of two things happens – either the testing code is removed or rewritten. In either case, we didn’t get the return on investment we expected on the first bit of testing code. Unfortunately, rare is the case where the relevant people in the organization understand why, resulting in the same situation repeating itself over and over again.

Those projects would have been better off without unit testing, though the organization as a whole might have used those experiences to learn and improve. It’s been my experience that if the organization wasn’t conscious enough in the context of the project to notice the situation, it is unlikely to do so at higher levels.

On fragile unit tests

The reason that a unit test ends up being rewritten (or removed) is that its code was coupled to the production code in such a way that it broke when the production code changed. This tendency to break (fragility) is a critical property of a unit test. A fragile unit test will slow down a developer doing work on some existing code – it actually makes the system less maintainable.

For a unit test code to be stable (not fragile) it needs to be coupled to stable properties of the production code. The question of whether the production code is designed in such a way that it has stable properties – is a design question. Is it a unit? If not, you will not be able to write a unit-test against it.

And anyway, who said that every class is a unit, or should be a unit? Domain models (when done right) are good examples of a unit, yet the classes that make them up may not be units. Unit-testing should only be attempted with things which are units.

I think too much weight is put on whether a dependency of a class is a concrete or interface type, and not nearly enough on the nature of the dependency. I wouldn’t blame the hammer for pounding my thumb, and by the same token I think that blame should not be directed towards tools like those from TypeMock.

On tools

There is so much more depth to both design and testability that needs to be more broadly understood. No tool has yet been created to handle either design or testing in such a way that humans can give up responsibility for the outcome.

Over the years I’ve noticed that tools are most significant when used by skilled practitioners, which makes sense in retrospect. Giving a novice carpenter a laser-guided saw probably won’t significantly change the outcome of their work. Ultimately, the skilled practitioners are the ones that create tools – not the novices. And no tool, no matter how advanced, will make a novice perform at levels like the skilled practitioner.

In the case of a project too big for a single skilled practitioner to complete in the time required (or at all), the balance of importance shifts away from tools to the project management topics described above.

In summary

I hope that this post has shed some light on the context in which decisions with respect to testing need to be made. Design is one activity that can support certain kinds of testing, but not the only one, or even the most important one for the given type of testing necessary at that time in the project.

Design is hard. Project management is hard. Testing is hard.

Getting the right mix of people that together have enough experience and skills in these activities isn’t easy.

Don’t expect that sprinkling some interfaces in your code base will be enough.
That doesn’t count much in the way of design, just as writing code in a testing namespace doesn’t count much in the way of testability.

Looking forward to hearing your comments.



On Small Applications

Sunday, March 7th, 2010

smallI hear this too often: “X sounds like a great pattern, but it’s overkill for small applications”. Many patterns have been subjected to this including (but not limited to): SOA, DDD, CQRS, ORM, etc. Often the statement is made by a person without experience in the given pattern (though possibly experienced in other patterns). Let’s take a look at the second part – the “small application”, and ask:

What makes an app small?

Or inversely, what makes an app warrant the “enterprise” moniker?

If there’s one thing that the history of our industry has shown repeatedly, it’s that developers aren’t particularly accurate with their estimates. Like, orders-of-magnitude inaccurate. Knowing this, it’s surprising that the “small app” argument seems to win so many arguments. The same goes for justifications in the form of “we’ve got to have an X, this is a BIG project”.

So, what makes an app small?

Is it a small number of lines of code? Well, what if those lines of code are keeping planes in the air?

Is it a small number of developers? Same as above. Actually, history has shown that some of the most valuable bits of code written were done by small numbers of developers.

Is it that it will only be installed on a single machine?

Is it…

What could it be?

The real issue

The small app argument is a diversionary tactic.

Loosely translated, it means “I’m comfortable where I am and I don’t want to change”.

Moving on…

The real story of size

Once we actually look at the specific context of an app, we tend to see that someone cares a great deal about it, enough to finance its custom development – rather than buying an off-the-shelf alternative. The expected lifetime of business use is easily 3-5 years, if not 7-10, during which many enhancements will likely be requested. Thus, some non-functional properties of the code matter – at the very least maintainability.

In which case, if the given pattern or approach does significantly improve the desired non-functional properties of the app, it only makes sense to use it.

There is one class of software that might possibly be treated as “small” – the one-off script that’s written to automate some IT task. And even then, so many of these scripts end up living longer than the apps themselves that they should be engineered at the same level of quality.

In closing

Don’t counter a “small app” argument with psychology.
It will only make matters worse.

Instead, rephrase the issue around the lifetime of business use.

I’ve found that there are precious few cases where the harsh light of reality doesn’t help the appropriate decisions be made. If indeed this is a small-lifetime-app, just drag-and-drop until you’re done. Otherwise, the time it takes to understand and evaluate the applicability of the given patterns will definitely pay itself back many times over the life of the app.

And managers, keep your ears open for it. The technical risks behind that statement are icebergs waiting to sink your project.

* with thanks to Mike Nichols for pushing my buttons.



Unit Testing for Developers and Managers

Tuesday, September 30th, 2008

image “We need to rewrite the system.”

Thus begins the story of yet another developer trying to convince their manager to adopt test-driven development (or any other methodology or technology). There’s a good chance this developer’s been reading all sorts of stuff on blogs (like those linked here) that have convinced him that salvation lies that way.

Don’t get me wrong.

There’s a good chance the developer’s right.

It’s just that that’s besides the point.

Developers and Managers

There’s a difference between how developers view a practice and how a manager (defined for the purposes of this post as someone in charge of delivering something) view that same practice. From a developer perspective, Ian’s point about unit testing is spot on:

“The problem is that the most important step is not doing it right, but doing it at all.”

Yet, as Ian himself points out in the title, this is a learning issue. If you want to learn to swim, there’s no replacement for jumping in the pool.

The manager’s perspective is a bit different.

Yes, we want our developers to improve their skill set. Yes, we understand that unit testing will ultimately improve quality. Yes, we know developers need to practice these skills as a part of their job. But, and it’s a big ole’ but, when it comes time to sink or swim, and we’ve got a deadline, those desires need to be balanced with delivering. Accounts of unit testing adoption efforts resulting in more (test) code to support with little apparent improvement in quality in the short term, well, they scare us. Arnon’s post gives more links supporting that feeling.

What’s a Unit Test anyway?

Is it any class that happens to have a TestFixture attribute on it?

If we are to “decouple” unit testing from good design, as Roy has described, that’s a not-improbable outcome. If the design of the system is such as there aren’t any real “units”, what exactly are we testing? Regardless of static or dynamic typing, replaceability of code, and other technological things, does the fact that all TestMethods in that TestFixture complete successfully mean anything? In other words, what did the test test?

It is clear that these tests cost something.

It’s more code to write. It’s more code to maintain.

The question is, what value are we getting from these “unit tests that any developer without design skills can write”?

The manager in me doesn’t like this return on investment.

By the way, TDD is as much the evolution of unit testing as the screw driver is the evolution of the hammer. But that’ll have to wait for a different post.

What’s Design Got To Do With It?

If you’re looking for the technical ability to write a test fixture and replace calls to other classes, then design has nothing to it.

If tests are to be valuable – design has everything to do with it.

The difficulty our developer is having unit-testing the system is a symptom of design problems. There’s a good chance that’s why he suggested a rewrite.

By the way, please do a search & replace in your vocabulary on the word “rewrite” with the word “redesign”. The code’s syntax isn’t the problem – it’s not the “m_”, camel case, or anything like that. It’s not that if the code was rewritten under the same design that all problems will go away.

Redesign, or do nothing.

The community’s been discussing the issues of coupling, interfaces, mocking, and tools at length in the context of testability. I won’t reiterate the debate here but I’ll tell you this:

If logic is duplicated, if the code is tightly coupled, if there is no separation of concerns, the unit tests will be useless – even if they “test” the class in isolation.

Cut the coverage crap

Metrics lie.

The fact that there’s a bunch of other code which calls 100% of the system’s code and doesn’t contain false assertions doesn’t mean that the code is high quality or doesn’t contain bugs.

In a well designed system, most “logic” will be contained in two “layers” – the controllers and the domain model. These classes should be independent of any and all technological concerns. You can and should get high unit test coverage on classes in these layers. Shoot for 100%, it’s worth it.

Testing domain models is all about asserting state. While using setters to get the domain objects into a necessary initial state is OK, setters should not be used beyond that. Testing controllers is primarily about interactions – mocks will probably be needed for views and service agents. Commands do not need to be mocked out.

Most other layers have some dependence on technology that makes unit tests relatively less valuable. Coverage on these layers is most meaningless. My guidance is to take the effort that would have been spent on unit testing these other layers and invest it all in automated integration tests. You’re likely to get a much higher return on investment. Much higher.

Much.

Everybody’s Right

Developers aren’t just born knowing good design, testing, or anything else. Universities, colleges, and most vendors do little to change that state of affairs. Books help, a bit, but when learning to swim, you’ve got to get your feet wet, and on the job training is, by and large, all there is. As such, lowering the barrier to entry is important.

Keeping in mind the Dreyfus model of knowledge acquisition, it’s not about “dumbing down” software development, it’s about bringing novices up to speed:

“In the beginning [novices] learn to recognize objective facts and features, relevant to the skill. Characteristic of relevant elements are that they can be recognized context-free, i.e. without reference to the overall situation. The novice acquire basic rules to follow, acting upon those facts and features. The rules are also context-free, i.e. no notice is taken to the surroundings. On account of this the novice feels very little responsibility for the result.” (emphasis mine)

Managers are ultimately responsible for the result.

Managers shouldn’t necessarily sacrifice their projects on this altar of learning. Organizations need to find ways for developers to safely practice these techniques as a part of developing their “human resources”. First of all, this needs to be communicated to everyone – that the organization understands the importance of these techniques, the desires of developers to adopt them, and the projects that need to be delivered.

Some projects may be allocated additional non-functional requirements: the software will be developed test-first, there will be at least 80% unit test coverage, etc. It can make sense to have developers spend some time on these projects after finishing one more delivery focused project and before going onto another one. As more developers become proficient with unit testing and design, the delivery focused projects can start to benefit from these skills.

It’s a gradual process.

The Important Bit

No matter how you go about unit testing, do periodic test reviews.

Just like code reviews.

That’s it.

 


Related Posts

Business Process Verification

Self documenting and Test-Driven Alien Artifacts

SOA Testing



   


Don't miss my best content
 

Recommendations

Bryan Wheeler, Director Platform Development at msnbc.com
Udi Dahan is the real deal.

We brought him on site to give our development staff the 5-day “Advanced Distributed System Design” training. The course profoundly changed our understanding and approach to SOA and distributed systems.

Consider some of the evidence: 1. Months later, developers still make allusions to concepts learned in the course nearly every day 2. One of our developers went home and made her husband (a developer at another company) sign up for the course at a subsequent date/venue 3. Based on what we learned, we’ve made constant improvements to our architecture that have helped us to adapt to our ever changing business domain at scale and speed If you have the opportunity to receive the training, you will make a substantial paradigm shift.

If I were to do the whole thing over again, I’d start the week by playing the clip from the Matrix where Morpheus offers Neo the choice between the red and blue pills. Once you make the intellectual leap, you’ll never look at distributed systems the same way.

Beyond the training, we were able to spend some time with Udi discussing issues unique to our business domain. Because Udi is a rare combination of a big picture thinker and a low level doer, he can quickly hone in on various issues and quickly make good (if not startling) recommendations to help solve tough technical issues.” November 11, 2010

Sam Gentile Sam Gentile, Independent WCF & SOA Expert
“Udi, one of the great minds in this area.
A man I respect immensely.”





Ian Robinson Ian Robinson, Principal Consultant at ThoughtWorks
"Your blog and articles have been enormously useful in shaping, testing and refining my own approach to delivering on SOA initiatives over the last few years. Over and against a certain 3-layer-application-architecture-blown-out-to- distributed-proportions school of SOA, your writing, steers a far more valuable course."

Shy Cohen Shy Cohen, Senior Program Manager at Microsoft
“Udi is a world renowned software architect and speaker. I met Udi at a conference that we were both speaking at, and immediately recognized his keen insight and razor-sharp intellect. Our shared passion for SOA and the advancement of its practice launched a discussion that lasted into the small hours of the night.
It was evident through that discussion that Udi is one of the most knowledgeable people in the SOA space. It was also clear why – Udi does not settle for mediocrity, and seeks to fully understand (or define) the logic and principles behind things.
Humble yet uncompromising, Udi is a pleasure to interact with.”

Glenn Block Glenn Block, Senior Program Manager - WCF at Microsoft
“I have known Udi for many years having attended his workshops and having several personal interactions including working with him when we were building our Composite Application Guidance in patterns & practices. What impresses me about Udi is his deep insight into how to address business problems through sound architecture. Backed by many years of building mission critical real world distributed systems it is no wonder that Udi is the best at what he does. When customers have deep issues with their system design, I point them Udi's way.”

Karl Wannenmacher Karl Wannenmacher, Senior Lead Expert at Frequentis AG
“I have been following Udi’s blog and podcasts since 2007. I’m convinced that he is one of the most knowledgeable and experienced people in the field of SOA, EDA and large scale systems.
Udi helped Frequentis to design a major subsystem of a large mission critical system with a nationwide deployment based on NServiceBus. It was impressive to see how he took the initial architecture and turned it upside down leading to a very flexible and scalable yet simple system without knowing the details of the business domain. I highly recommend consulting with Udi when it comes to large scale mission critical systems in any domain.”

Simon Segal Simon Segal, Independent Consultant
“Udi is one of the outstanding software development minds in the world today, his vast insights into Service Oriented Architectures and Smart Clients in particular are indeed a rare commodity. Udi is also an exceptional teacher and can help lead teams to fall into the pit of success. I would recommend Udi to anyone considering some Architecural guidance and support in their next project.”

Ohad Israeli Ohad Israeli, Chief Architect at Hewlett-Packard, Indigo Division
“When you need a man to do the job Udi is your man! No matter if you are facing near deadline deadlock or at the early stages of your development, if you have a problem Udi is the one who will probably be able to solve it, with his large experience at the industry and his widely horizons of thinking , he is always full of just in place great architectural ideas.
I am honored to have Udi as a colleague and a friend (plus having his cell phone on my speed dial).”

Ward Bell Ward Bell, VP Product Development at IdeaBlade
“Everyone will tell you how smart and knowledgable Udi is ... and they are oh-so-right. Let me add that Udi is a smart LISTENER. He's always calibrating what he has to offer with your needs and your experience ... looking for the fit. He has strongly held views ... and the ability to temper them with the nuances of the situation.
I trust Udi to tell me what I need to hear, even if I don't want to hear it, ... in a way that I can hear it. That's a rare skill to go along with his command and intelligence.”

Eli Brin, Program Manager at RISCO Group
“We hired Udi as a SOA specialist for a large scale project. The development is outsourced to India. SOA is a buzzword used almost for anything today. We wanted to understand what SOA really is, and what is the meaning and practice to develop a SOA based system.
We identified Udi as the one that can put some sense and order in our minds. We started with a private customized SOA training for the entire team in Israel. After that I had several focused sessions regarding our architecture and design.
I will summarize it simply (as he is the software simplist): We are very happy to have Udi in our project. It has a great benefit. We feel good and assured with the knowledge and practice he brings. He doesn’t talk over our heads. We assimilated nServicebus as the ESB of the project. I highly recommend you to bring Udi into your project.”

Catherine Hole Catherine Hole, Senior Project Manager at the Norwegian Health Network
“My colleagues and I have spent five interesting days with Udi - diving into the many aspects of SOA. Udi has shown impressive abilities of understanding organizational challenges, and has brought the business perspective into our way of looking at services. He has an excellent understanding of the many layers from business at the top to the technical infrstructure at the bottom. He is a great listener, and manages to simplify challenges in a way that is understandable both for developers and CEOs, and all the specialists in between.”

Yoel Arnon Yoel Arnon, MSMQ Expert
“Udi has a unique, in depth understanding of service oriented architecture and how it should be used in the real world, combined with excellent presentation skills. I think Udi should be a premier choice for a consultant or architect of distributed systems.”

Vadim Mesonzhnik, Development Project Lead at Polycom
“When we were faced with a task of creating a high performance server for a video-tele conferencing domain we decided to opt for a stateless cluster with SQL server approach. In order to confirm our decision we invited Udi.

After carefully listening for 2 hours he said: "With your kind of high availability and performance requirements you don’t want to go with stateless architecture."

One simple sentence saved us from implementing a wrong product and finding that out after years of development. No matter whether our former decisions were confirmed or altered, it gave us great confidence to move forward relying on the experience, industry best-practices and time-proven techniques that Udi shared with us.
It was a distinct pleasure and a unique opportunity to learn from someone who is among the best at what he does.”

Jack Van Hoof Jack Van Hoof, Enterprise Integration Architect at Dutch Railways
“Udi is a respected visionary on SOA and EDA, whose opinion I most of the time (if not always) highly agree with. The nice thing about Udi is that he is able to explain architectural concepts in terms of practical code-level examples.”

Neil Robbins Neil Robbins, Applications Architect at Brit Insurance
“Having followed Udi's blog and other writings for a number of years I attended Udi's two day course on 'Loosely Coupled Messaging with NServiceBus' at SkillsMatter, London.

I would strongly recommend this course to anyone with an interest in how to develop IT systems which provide immediate and future fitness for purpose. An influential and innovative thought leader and practitioner in his field, Udi demonstrates and shares a phenomenally in depth knowledge that proves his position as one of the premier experts in his field globally.

The course has enhanced my knowledge and skills in ways that I am able to immediately apply to provide benefits to my employer. Additionally though I will be able to build upon what I learned in my 2 days with Udi and have no doubt that it will only enhance my future career.

I cannot recommend Udi, and his courses, highly enough.”

Nick Malik Nick Malik, Enterprise Architect at Microsoft Corporation
You are an excellent speaker and trainer, Udi, and I've had the fortunate experience of having attended one of your presentations. I believe that you are a knowledgable and intelligent man.”

Sean Farmar Sean Farmar, Chief Technical Architect at Candidate Manager Ltd
“Udi has provided us with guidance in system architecture and supports our implementation of NServiceBus in our core business application.

He accompanied us in all stages of our development cycle and helped us put vision into real life distributed scalable software. He brought fresh thinking, great in depth of understanding software, and ongoing support that proved as valuable and cost effective.

Udi has the unique ability to analyze the business problem and come up with a simple and elegant solution for the code and the business alike.
With Udi's attention to details, and knowledge we avoided pit falls that would cost us dearly.”

Børge Hansen Børge Hansen, Architect Advisor at Microsoft
“Udi delivered a 5 hour long workshop on SOA for aspiring architects in Norway. While keeping everyone awake and excited Udi gave us some great insights and really delivered on making complex software challenges simple. Truly the software simplist.”

Motty Cohen, SW Manager at KorenTec Technologies
“I know Udi very well from our mutual work at KorenTec. During the analysis and design of a complex, distributed C4I system - where the basic concepts of NServiceBus start to emerge - I gained a lot of "Udi's hours" so I can surely say that he is a professional, skilled architect with fresh ideas and unique perspective for solving complex architecture challenges. His ideas, concepts and parts of the artifacts are the basis of several state-of-the-art C4I systems that I was involved in their architecture design.”

Aaron Jensen Aaron Jensen, VP of Engineering at Eleutian Technology
Awesome. Just awesome.

We’d been meaning to delve into messaging at Eleutian after multiple discussions with and blog posts from Greg Young and Udi Dahan in the past. We weren’t entirely sure where to start, how to start, what tools to use, how to use them, etc. Being able to sit in a room with Udi for an entire week while he described exactly how, why and what he does to tackle a massive enterprise system was invaluable to say the least.

We now have a much better direction and, more importantly, have the confidence we need to start introducing these powerful concepts into production at Eleutian.”

Gad Rosenthal Gad Rosenthal, Department Manager at Retalix
“A thinking person. Brought fresh and valuable ideas that helped us in architecting our product. When recommending a solution he supports it with evidence and detail so you can successfully act based on it. Udi's support "comes on all levels" - As the solution architect through to the detailed class design. Trustworthy!”

Chris Bilson Chris Bilson, Developer at Russell Investment Group
“I had the pleasure of attending a workshop Udi led at the Seattle ALT.NET conference in February 2009. I have been reading Udi's articles and listening to his podcasts for a long time and have always looked to him as a source of advice on software architecture.
When I actually met him and talked to him I was even more impressed. Not only is Udi an extremely likable person, he's got that rare gift of being able to explain complex concepts and ideas in a way that is easy to understand.
All the attendees of the workshop greatly appreciate the time he spent with us and the amazing insights into service oriented architecture he shared with us.”

Alexey Shestialtynov Alexey Shestialtynov, Senior .Net Developer at Candidate Manager
“I met Udi at Candidate Manager where he was brought in part-time as a consultant to help the company make its flagship product more scalable. For me, even after 30 years in software development, working with Udi was a great learning experience. I simply love his fresh ideas and architecture insights.
As we all know it is not enough to be armed with best tools and technologies to be successful in software - there is still human factor involved. When, as it happens, the project got in trouble, management asked Udi to step into a leadership role and bring it back on track. This he did in the span of a month. I can only wish that things had been done this way from the very beginning.
I look forward to working with Udi again in the future.”

Christopher Bennage Christopher Bennage, President at Blue Spire Consulting, Inc.
“My company was hired to be the primary development team for a large scale and highly distributed application. Since these are not necessarily everyday requirements, we wanted to bring in some additional expertise. We chose Udi because of his blogging, podcasting, and speaking. We asked him to to review our architectural strategy as well as the overall viability of project.
I was very impressed, as Udi demonstrated a broad understanding of the sorts of problems we would face. His advice was honest and unbiased and very pragmatic. Whenever I questioned him on particular points, he was able to backup his opinion with real life examples. I was also impressed with his clarity and precision. He was very careful to untangle the meaning of words that might be overloaded or otherwise confusing. While Udi's hourly rate may not be the cheapest, the ROI is undoubtedly a deal. I would highly recommend consulting with Udi.”

Robert Lewkovich, Product / Development Manager at Eggs Overnight
“Udi's advice and consulting were a huge time saver for the project I'm responsible for. The $ spent were well worth it and provided me with a more complete understanding of nServiceBus and most importantly in helping make the correct architectural decisions earlier thereby reducing later, and more expensive, rework.”

Ray Houston Ray Houston, Director of Development at TOPAZ Technologies
“Udi's SOA class made me smart - it was awesome.

The class was very well put together. The materials were clear and concise and Udi did a fantastic job presenting it. It was a good mixture of lecture, coding, and question and answer. I fully expected that I would be taking notes like crazy, but it was so well laid out that the only thing I wrote down the entire course was what I wanted for lunch. Udi provided us with all the lecture materials and everyone has access to all of the samples which are in the nServiceBus trunk.

Now I know why Udi is the "Software Simplist." I was amazed to find that all the code and solutions were indeed very simple. The patterns that Udi presented keep things simple by isolating complexity so that it doesn't creep into your day to day code. The domain code looks the same if it's running in a single process or if it's running in 100 processes.”

Ian Cooper Ian Cooper, Team Lead at Beazley
“Udi is one of the leaders in the .Net development community, one of the truly smart guys who do not just get best architectural practice well enough to educate others but drives innovation. Udi consistently challenges my thinking in ways that make me better at what I do.”

Liron Levy, Team Leader at Rafael
“I've met Udi when I worked as a team leader in Rafael. One of the most senior managers there knew Udi because he was doing superb architecture job in another Rafael project and he recommended bringing him on board to help the project I was leading.
Udi brought with him fresh solutions and invaluable deep architecture insights. He is an authority on SOA (service oriented architecture) and this was a tremendous help in our project.
On the personal level - Udi is a great communicator and can persuade even the most difficult audiences (I was part of such an audience myself..) by bringing sound explanations that draw on his extensive knowledge in the software business. Working with Udi was a great learning experience for me, and I'll be happy to work with him again in the future.”

Adam Dymitruk Adam Dymitruk, Director of IT at Apara Systems
“I met Udi for the first time at DevTeach in Montreal back in early 2007. While Udi is usually involved in SOA subjects, his knowledge spans all of a software development company's concerns. I would not hesitate to recommend Udi for any company that needs excellent leadership, mentoring, problem solving, application of patterns, implementation of methodologies and straight out solution development.
There are very few people in the world that are as dedicated to their craft as Udi is to his. At ALT.NET Seattle, Udi explained many core ideas about SOA. The team that I brought with me found his workshop and other talks the highlight of the event and provided the most value to us and our organization. I am thrilled to have the opportunity to recommend him.”

Eytan Michaeli Eytan Michaeli, CTO Korentec
“Udi was responsible for a major project in the company, and as a chief architect designed a complex multi server C4I system with many innovations and excellent performance.”


Carl Kenne Carl Kenne, .Net Consultant at Dotway AB
“Udi's session "DDD in Enterprise apps" was truly an eye opener. Udi has a great ability to explain complex enterprise designs in a very comprehensive and inspiring way. I've seen several sessions on both DDD and SOA in the past, but Udi puts it in a completly new perspective and makes us understand what it's all really about. If you ever have a chance to see any of Udi's sessions in the future, take it!”

Avi Nehama, R&D Project Manager at Retalix
“Not only that Udi is a briliant software architecture consultant, he also has remarkable abilities to present complex ideas in a simple and concise manner, and...
always with a smile. Udi is indeed a top-league professional!”

Ben Scheirman Ben Scheirman, Lead Developer at CenterPoint Energy
“Udi is one of those rare people who not only deeply understands SOA and domain driven design, but also eloquently conveys that in an easy to grasp way. He is patient, polite, and easy to talk to. I'm extremely glad I came to his workshop on SOA.”

Scott C. Reynolds Scott C. Reynolds, Director of Software Engineering at CBLPath
“Udi is consistently advancing the state of thought in software architecture, service orientation, and domain modeling.
His mastery of the technologies and techniques is second to none, but he pairs that with a singular ability to listen and communicate effectively with all parties, technical and non, to help people arrive at context-appropriate solutions. Every time I have worked with Udi, or attended a talk of his, or just had a conversation with him I have come away from it enriched with new understanding about the ideas discussed.”

Evgeny-Hen Osipow, Head of R&D at PCLine
“Udi has helped PCLine on projects by implementing architectural blueprints demonstrating the value of simple design and code.”

Rhys Campbell Rhys Campbell, Owner at Artemis West
“For many years I have been following the works of Udi. His explanation of often complex design and architectural concepts are so cleanly broken down that even the most junior of architects can begin to understand these concepts. These concepts however tend to typify the "real world" problems we face daily so even the most experienced software expert will find himself in an "Aha!" moment when following Udi teachings.
It was a pleasure to finally meet Udi in Seattle Alt.Net OpenSpaces 2008, where I was pleasantly surprised at how down-to-earth and approachable he was. His depth and breadth of software knowledge also became apparent when discussion with his peers quickly dove deep in to the problems we current face. If given the opportunity to work with or recommend Udi I would quickly take that chance. When I think .Net Architecture, I think Udi.”

Sverre Hundeide Sverre Hundeide, Senior Consultant at Objectware
“Udi had been hired to present the third LEAP master class in Oslo. He is an well known international expert on enterprise software architecture and design, and is the author of the open source messaging framework nServiceBus. The entire class was based on discussion and interaction with the audience, and the only Power Point slide used was the one showing the agenda.
He started out with sketching a naive traditional n-tier application (big ball of mud), and based on suggestions from the audience we explored different solutions which might improve the solution. Whatever suggestions we threw at him, he always had a thoroughly considered answer describing pros and cons with the suggested solution. He obviously has a lot of experience with real world enterprise SOA applications.”

Raphaël Wouters Raphaël Wouters, Owner/Managing Partner at Medinternals
“I attended Udi's excellent course 'Advanced Distributed System Design with SOA and DDD' at Skillsmatter. Few people can truly claim such a high skill and expertise level, present it using a pragmatic, concrete no-nonsense approach and still stay reachable.”

Nimrod Peleg Nimrod Peleg, Lab Engineer at Technion IIT
“One of the best programmers and software engineer I've ever met, creative, knows how to design and implemet, very collaborative and finally - the applications he designed implemeted work for many years without any problems!

Jose Manuel Beas
“When I attended Udi's SOA Workshop, then it suddenly changed my view of what Service Oriented Architectures were all about. Udi explained complex concepts very clearly and created a very productive discussion environment where all the attendees could learn a lot. I strongly recommend hiring Udi.”

Daniel Jin Daniel Jin, Senior Lead Developer at PJM Interconnection
“Udi is one of the top SOA guru in the .NET space. He is always eager to help others by sharing his knowledge and experiences. His blog articles often offer deep insights and is a invaluable resource. I highly recommend him.”

Pasi Taive Pasi Taive, Chief Architect at Tieto
“I attended both of Udi's "UI Composition Key to SOA Success" and "DDD in Enterprise Apps" sessions and they were exceptionally good. I will definitely participate in his sessions again. Udi is a great presenter and has the ability to explain complex issues in a manner that everyone understands.”

Eran Sagi, Software Architect at HP
“So far, I heard about Service Oriented architecture all over. Everyone mentions it – the big buzz word. But, when I actually asked someone for what does it really mean, no one managed to give me a complete satisfied answer. Finally in his excellent course “Advanced Distributed Systems”, I got the answers I was looking for. Udi went over the different motivations (principles) of Services Oriented, explained them well one by one, and showed how each one could be technically addressed using NService bus. In his course, Udi also explain the way of thinking when coming to design a Service Oriented system. What are the questions you need to ask yourself in order to shape your system, place the logic in the right places for best Service Oriented system.

I would recommend this course for any architect or developer who deals with distributed system, but not only. In my work we do not have a real distributed system, but one PC which host both the UI application and the different services inside, all communicating via WCF. I found that many of the architecture principles and motivations of SOA apply for our system as well. Enough that you have SW partitioned into components and most of the principles becomes relevant to you as well. Bottom line – an excellent course recommended to any SW Architect, or any developer dealing with distributed system.”

Consult with Udi

Guest Authored Books
Chapter: Introduction to SOA    Article: The Enterprise Service Bus and Your SOA

97 Things Every Software Architect Should Know



Creative Commons License  © Copyright 2005-2011, Udi Dahan. email@UdiDahan.com