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Udi & Greg Reach CQRS Agreement


Posted in Architecture | CQRS | DDD | EDA | SOA

Lion--Tiger-psd74183Hard to believe, isn’t it?

Although both myself and Greg have been saying (quite publicly) for a long time now that we’re in agreement in about 99% of the DDD/CQRS content we talk about, it turns out the terminology we use has made it very difficult for everybody else to see that.

Anyway, on a recent call with Greg and the Microsoft Patterns & Practices team working on the CQRS guidance, I think we finally ironed out the terminological differences.

First of all, both of us clearly stated that CQRS is not meant to be the top-level architecture of a system.

The use of Bounded Contexts from Domain Driven Design is a good way to *start* handling that top-level.

The area of some contention was how big a Bounded Context should be. After going back and forth a bit, Greg brought the concept of Business Component into the conversation, and that really cleared things up all around. I was quite pleased as I’ve been going on and on about these business components for years (I think 2006 was one of my earlier posts on the topic, though the mp3 has disappeared since then).

Anyway, here’s the meat:

A given Bounded Context should be divided into Business Components, where these Business Components have full UI through DB code, and are ultimately put together in composite UI’s and other physical pipelines to fulfill the system’s functionality.

A Business Component can exist in only one Bounded Context.

CQRS, if it is to be used at all, should be used within a Business Component.

There you have it – terminological agreement in addition to the philosophical agreement that was always there.

You can find the history of my posts mentioning Business Components here.

Comments [16]
Posted on Friday, February 10th, 2012.



Change is hard


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.

Comments [6]
Posted on Sunday, January 8th, 2012.



Talks, NServiceBus Beta, and Course Registration


Some links to things that don’t fit anywhere else:

Andreas Ohlund’s talk on New and Shiny things in NServiceBus 3.0 is available here.

By the way, we’ve now got a beta out of NServiceBus 3.0 – get it here.

Yves Goeleven will be giving a talk on simplifying distributed application development with NServiceBus and the Windows Azure Platform on Jan 31 – details here.

Carl and Richard over at Dot Net Rocks interviewed me at the Oredev conference in Sweden about Domain Driven Design and one of my pet peeves – the use of Customer in example applications. Get it here.

I’m also happy to announce that registration for my 5-day Advanced Distributed Systems Design course has now opened for Bad Ems Germany and New York, in addition to the already open registrations for Austin TX and London. Information and registration on my training page.

I’ve also made some progress with the recording of the course – you can now access days 1, 2, and part of day 3 – covering distributed systems theory, coupling, messaging patterns, bus and broker architectural style, SOA building blocks, and the hotel management SOA exercise. Information and purchase available here.

Comments [7]
Posted on Wednesday, January 4th, 2012.



The Myth Of “Infinite Scalability”


globeScalability is a topic near and dear to my heart.

Many a client seeks me out for the first time for help in this area.

Usually the request is for an amount substantially smaller than infinity.

It’s usually on the discussion groups and in conference presentations that infinity is brought into it.

The basics

The first issue with scalability is the use of the word as an adjective: scalable.

“Is the system scalable?”

Or the similar verb use: “Does it scale?”

The problem here is the implication that there is a yes/no answer to the question.

Scalability is not boolean.

Linear Scalability

scalabilityWhen people talk about scalability, or a system being able to scale, they’re usually referring to a graph that looks something like this:

The red graph indicating a system that does not scale well, the green graph indicating one that does.

What is missing from this diagram are the labels of the axes.

The Y axis is Cost, Expense, or Money.
The X axis is usually the number of users (for internet-type companies).

Ultimately, scalability is a cost-function that will tell us how much it will cost to have the system support a certain number of users.

Linear scalability is when the cost of the next user is the same as the cost of the previous user. This means our system doesn’t have bottlenecks. This is what people usually mean when they say “infinite scalability”.

But there’s more

As many of the internet companies (and their investors) have realized over the years, there’s a difference between the number of users and the number of active users. It’s very easy to scale to a billion users when only 1000 of them are active at any given time.

To be more accurate, what we want is additional X-axes for things like total data managed by the system, number of requests per user, resource utilization per request, propagation speed (how quickly information entered by one user needs to be visible to others), and more.

Scalability is a multi-dimensional cost function, where part of an architects job is to figure out which dimensions are significant for the system/business, and what the expectation for growth is across each axis.

Preparing for “infinity”

Be careful not to optimize for only a single dimension – reality is a whole lot more complex.

There are so many other things to deal with as a system scales.

For example, do you really think you’re going to want your configuration entirely centralized? Putting everything in one place means easier management, yes, but it also means a mistake will instantly affect everyone. Is it worth the risk? Maybe instead of centralization, we could do with some automation that will allow a staged rollout of configuration changes with the ability to rollback.

The same goes for rolling out new versions, patches, and upgrades.

But that now means we may have multiple versions of the same system in production at the same time. How will that work? Will they all talk to the same database? How will we version the database then? If not, how will we handle state? Won’t this mean our code will have to be backwards compatible from one version to another? Isn’t that hard? Like, insanely hard?

Please, can we park the whole “infinite scalability” thing?
It’s really not the most important concern – not by a long shot.

Comments [13]
Posted on Thursday, December 29th, 2011.



MSMQ Info


Posted in MSMQ

In my courses and conference presentations in which I mentioned the use of MSMQ, I usually state that it comes installed on all versions of Windows going back to Win 2000 (unlike other queuing systems requiring an explicit install). Although installed, the MSMQ service does need to be turned on.

Anyway, it turns out that in the Server Core installations of Windows Server 2008 R2, MSMQ does NOT come pre-installed, and for a while it wasn’t even possible to add it (as John Breakwell described here).

Luckily, Microsoft has put MSMQ in the Developer Preview of Server 8 (as Brian Buvinghausen has written here).

Just wanted to call this out in case any of you get stuck on it.

BTW, the training schedule for Q1 of next year is now online, including Germany in February and NYC in March.

Check it out.

Comments [2]
Posted on Monday, December 26th, 2011.



Recording of joint interview with Eric Evans


Last month both myself and Eric Evans spoke at a conference run by the International Association of Software Architects (IASA) in Madrid. Eric talked about DDD and I talked about CQRS. While the talks were recorded, I don’t think they’ve come online yet.

At the end of the conference, we were interviewed by the local .NET magazine dNM and that video is now available here. We covered the background on things like DDD, CQRS, and the Cloud. I don’t think that either of us said anything earth-shattering but if you have half an hour, take a look:

Comments [1]
Posted on Wednesday, November 30th, 2011.



It’s not about you


Posted in Coaching | Life

its_totally_youThe first rule to keep in mind about getting what you want is:

It’s not about you.

How’s that for counter-intuitive.

In fact, the more you focus on yourself and trying to get what you want, the more you end up pushing away exactly the thing you’ve been trying to get.

A big part of the reason is:

If what you wanted was entirely under your control, well, you’d already have it.

The fact that you want it indicates that you don’t have full, or often any, control.

Attempting to gain control, as a way of getting what you want, ultimately results in some kind of power struggle (sometimes you may not even realize that this is happening). The thing is that it’s not very smart to engage in a power struggle when you’re not the one with much control/power.

To the outside world, this attempt may look, at best, futile and at worst, childish – and, if anything, indicates that you really aren’t ready to be given what you want.

Comments [14]
Posted on Monday, November 28th, 2011.



How do I get what I want?


Posted in Coaching | Life

lotus_flowerSo, once again, it’s time for something a little different.

Through my work with clients over the years, a common theme has popped up that I haven’t been addressing on this blog up until now. I haven’t yet found a good word to describe this theme, as it is kind of on the nexus of organizational politics, personal development, power, authority, expertise, knowledge, emotional intelligence, and a bunch of other things.

Questions, questions

You see, whenever working with clients, or even when I do my public training courses, when everybody understands my recommendations – what needs to be done, and how that will address the problems they’ve been having – the question invariably pops up: how can we possibly get them (the rest of the organization, our boss, whoever) to let us do this?

I feel that, up until now, I haven’t been giving as much guidance on that side of the equation:

  • the “how do I do what I know to be right without getting fired?” question;
  • for consultants, the “how do I get my clients to listen to me – to act on my recommendations?” question;
  • for managers, the “how do I get my team on board – to follow where I lead?” question

So, in addition to my regular blogging topics I’m going to add the above topics as well.

In short, I’m going to be talking about the answer to the “how do I get what I want?” question.

How do I get what I want?

In the past decade or so, interacting with thousands of people in hundreds of organizations, and in the hundred or so books I’ve digested (and put into practice) on the topic, this seems to be the universal question. During this time, I’ve always shied away from getting into this with clients. It felt out of bounds – off limits, except for the things directly related to the work at hand – even though I knew I could do so much more for them.

In only a handful of cases did I actually go deep, and it was life-altering (for me as well as the client).

While I can’t say that I’ve got it all figured out, in my relatively short time on this planet I’ve managed to get quite a lot of boxes ticked (like finances and living my dream). It’s like I was pre-programmed for a lot of this stuff.

Some things are a never-ending balancing act like “how can I manage all the travel that living my dream entails while still being a loving husband and father?” In my case, it’s 4 little ones – 10, 8, 6, and 10 months, a wife who’s doing her masters in law in parallel to regular work, and me flying out at least twice a month (usually at least a week at a time).

Can’t wait?

For those of you who can’t wait for the blog posts to slowly trickle out, I’m happy to offer one-on-one guidance and coaching similar in form to my regular remote consulting model. If you’re interested contact me at coaching@udidahan.com.

Anyway, I hope this additional aspect to what I do will help you successfully apply all the software things that I’ve been talking about in your current job as well as make the most out of the rest of your career, and your life.

Oh, and the answer to THE question? It’s “just ask”. 🙂

I’d really love to hear your comments and thoughts on this additional twist to our ongoing relationship.

Best regards,

— Udi

Comments [5]
Posted on Thursday, November 24th, 2011.



Rackspace TechTalk Online


Posted in Uncategorized

Last week I was at Rackspace and gave a TechTalk – an open Q&A that dealt primarily with SOA. The recording is now online here.

Comments
Posted on Monday, November 21st, 2011.



Training – US, Europe, and now Virtual!


Posted in Courses

After the smashing success of my course in San Francisco, I’m happy to announce the opening of the next one in the US. This time I’m going to be giving it in Austin Texas from Jan 23 to 27 2012. Details and registration available here.

If you’re on the other side of the Atlantic, you can catch me in Stockholm on Nov 28 or in London on Dec 12.

On a related note, when I gave the course in Australia I had it recorded.

I know that there are some of you who can’t get your companies to give you time off to go to one of my courses so I hope that this virtual training thing will help. It’s quite a lot of video and, it turns out, there aren’t a lot of companies who make it easy to sell videos online. I’ve found one that looks very reasonable, but the visual design side of things still requires a fair bit of tweaking to make it look good.

Regardless, even though it looks ugly, even though not all of the videos are up yet, I wanted to make it available for all of you as quickly as possible. So here it is.

This is my first time doing something like this so please give me feedback on how to improve. Hopefully the platform that I’ve chosen will enable me to incorporate as much of your ideas as possible.

Comments [7]
Posted on Thursday, November 10th, 2011.



   


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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.”

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