Udi Dahan   Udi Dahan – The Software Simplist
Enterprise Development Expert & SOA Specialist
 
  
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On Mookid joining NServiceBus, and what that means for Rebus


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.

Comments
Posted on Wednesday, September 11th, 2013.



The right methodology for your project


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.

Comments [4]
Posted on Sunday, August 4th, 2013.



NServiceBus 4.0 Released!


Posted in NServiceBus

champaignIt’s here!

NServiceBus version 4.0 is now out.

Hard to believe it’s been more than 7 years since I started on this journey.

I know I always say this, but this is our biggest release ever. It’s been over a year since we released version 3.0 and in that time, the adoption of NServiceBus has totally exploded. I know I always talk about the big brand names but there have been hundreds of small to medium companies that have been seeing real success on this platform.

OK – one big name. I feel like I have to. If you’ve been to McDonald’s and purchased a happy meal for your kids – that’s going through NServiceBus. Yeah, at any McDonald’s around the world – and not just happy meals.

What’s in the box

While NServiceBus has historically used MSMQ as its primary queuing infrastructure, we now support RabbitMQ and ActiveMQ out of the box so you have full AMQP compliance at the wire level, and we’re soon going to be releasing a fully supported IBM MQ transport.

You can see the complete release notes for version 4 of NServiceBus here.

For those organizations who’ve been ignoring NServiceBus until now because they prefer having everything in a central database, we now support using database tables as queues.

While I’ve always been big on queuing infrastructure, I understand that it takes time for an organization to change and I hope that this will provide a smooth transition path.

Try it online now

If you’re in a locked-down corporate environment that won’t let you install anything on your box, but you’d still like to try NServiceBus out, we’ve got the solution for you.

Try our new hands-on labs – you’ll get remote access to a machine in the cloud with NServiceBus pre-installed on it ready to go.

We’ve even got a scale-out lab where you’ll see just how easy it is to build a 4 machine NServiceBus solution.

Try the labs.

Modeling

I’ve talked before about some modeling tools we’ve been working on for NServiceBus and I’m happy to say that they’re now ready for public beta. Instead of the name NServiceBus Studio (which overlapped far too much with Visual Studio), we’re now calling this ServiceMatrix.

ServiceMatrix

ServiceMatrix makes building message-driven service-oriented solutions an absolute joy allowing you to operate at much higher levels of abstraction. Find out more here.

Debugging

While the looser-coupling of message-driven systems makes them more scalable and maintainable, it does make debugging harder since you can’t just step-through one function to another when everything is invoked asynchronously.

For that reason, we’ve been working on visualization and management tooling to make things easier. By leveraging the built-in auditing of NServiceBus, we can show you the message causation chain – which command caused which event, which in turn caused what other messages to flow. We also hook into the error queue to show you when messages fail (in orange below) and the full stack trace of the exception.

Of course, you can always see the full body and headers of each message.

ServiceInsight

This tool, called ServiceInsight is now in its second beta and the feedback has been overwhelming – “oh my God, how could you have waited this long to release this?! Even our testers and admins are using it.”.

In Particular

Particular SoftwareYou might have noticed that all of these links are going to the Particular.net domain, and that the existing NServiceBus.com now redirects there as well.

After talking things over internally, the team agreed that we wanted to be much more than “just” a service bus. The new products I mentioned above are the first step in that direction, but there is more to come.

We wanted a name that wouldn’t pigeon-hole us but, I’ve got to tell you, it’s extremely hard to find a name for a software company (and a corresponding domain) that isn’t already taken.

When we hit on the name Particular Software and saw that ParticularSoftware.com was open, we were quite thrilled. You see, we’re very particular about the software we use, and we want to write software for people who are just as discerning as us. Getting Particular.net was nice too.

In closing

I want to take this opportunity to thank our community for believing in us all this time, and an especially big thank you to our community champions who have been gently shepherding thousands of new users in their first NServiceBus steps.

To our partners that have been building solutions for their customers on NServiceBus – you have our deepest appreciation. We’ve also got some new things coming just for you that you’ll really like.

By the way, if you’re an independent consultant or working at a consulting company and would like partner with us, please reach out to us.

And, although we’re constantly growing the team – it seems like there’s always so much more to be done. When I started down this path over 7 years ago, I never imagined that this could go on this long. Today, I’m pretty sure that there’s at least another 7 years more to go.

We’re dedicated to making this the best service platform out there.

Check it out.

Comments [12]
Posted on Thursday, July 11th, 2013.



Ask Udi 1: Alternative Architectures & Preaching to the Unconverted


As promised, the podcast is back.

Download episode 1 here      and then      Subscribe to the feed.

There were 16 questions submitted and a couple hundred votes for the various topics. I was able to cover the top two questions.

Do you have a question you want to ask?
Want to vote on which questions will be answered next week?
Click here

This week’s questions

Rob Eisenberg asked:

It seems that every project I walk into has the exact same architecture, regardless of what the company is building. It’s that standard 3-tier pattern: data-business-presentation. But, there are other large-scale architectural patterns available. I’d love to hear some case studies that pair business problems with the rationale for choosing an “alternative architecture.”

And since it’s not just about knowing the right approach but also being able to convince others, I included Rvonwink’s question too:

Some of us see the genuine benefits of pub/sub, EDA and SOA design. However, how do you go about persuading the cynics, time pressed and uninformed:

Our developers hate debugging pub/sub models; Others love the ‘simplicity’ of monolithic domains; Our DBA questions why messaging is required (since “the bus simply persists messages elsewhere”); Our sys admins hate deploying new applications or changing the deployment topology; Our boss is scared to tell the business there is a little extra work to start splitting apart services.

Next week

Currently the top questions for next week are:

  • Composite UI, Business Components and Deployment
  • How to handle predetermined technology choices
  • How do you manage NULL pointer exception in general?

What would you like to hear? Let me know.

Until next week…

Comments [5]
Posted on Friday, June 28th, 2013.



The “Ask Udi” podcast is back


Given the overwhelming feedback to revive the “Ask Udi” podcast, how could I refuse.

Please submit your questions over here or vote on questions that other people have asked.

Even if you don’t have a specific question, please feel free to suggest a topic that you’d like me to rant about (CQRS for example).

The podcast used to be supported by an online magazine and I didn’t think to back up the old podcast episodes so some have been lost in the ether, but you can find some of the history here: http://www.udidahan.com/category/ask-udi-podcast/.

Let’s see if we can get a podcast out by the end of next week – so go and suggest the topics you want to here about:

Submit your topic now

Comments [2]
Posted on Friday, June 21st, 2013.



Recording of my June 2013 Q&A at Skills Matter online


When I was in London last week teaching my 5-day course I gave an open Q&A on one of the evenings. The recording of that talk is now online here.

It was interesting to see that while many people came to the Q&A, there weren’t a whole lot with questions.

In any case, I was wondering if online the situation would be much different.

Some time ago I had a monthly podcast called “Ask Udi” and I was thinking of reviving that.

What do you think? Is that something you’d like? Leave me a comment.

And if you missed the course in London, I’m giving just one more course this year – here in Israel from June 30 – July 4. For details and registration, check out the Sela website.

Comments [17]
Posted on Thursday, June 13th, 2013.



Queries, Patterns, and Search – food for thought


fishWith all the talk of CQRS, the area that doesn’t get enough treatment (in my opinion) is that of queries. Many are already beginning to understand the importance of task-based UIs and how that aligns to the underlying commands being sent, validated, and processed in the system as well as the benefits of messaging-centric infrastructure (like NServiceBus) for handling those commands reliably. When it comes to queries, though, it isn’t nearly as well understood what it means for a query to be “task based”.

Starting with CRUD

Let’s start with a traditional CRUD application and work our way out from there.

In these environments, we often see users asking us to build “excel-like” screens that allow them to view a set of data as well as sort, filter, and group that data along various axes. While we might not get this requirement right away, after some time users begin to ask us to allow them to “save” a certain “query” that they have set up, providing it some kind of name.

That, right there, is a task-based query and it is the beginning of deeper domain insight.

Pattern matching

Any time a user is repeatedly running the same query (this can be once a day or some other unit of time) there is some scenario that the business is trying to identify and is using that user as a pattern-matching engine to see if the data indicates that that scenario has occurred.

It’s quite common for us to get a requirement to add some field (often a boolean or enum) to an entity which defaults to some value and then see that same field used in filtering other queries. These measures are sometimes instituted as a temporary stop-gap while a larger feature is being implemented, though (as the saying goes) there is nothing more permanent than a temporary solution.

Where we developers go wrong

The thing is, many developers don’t notice these sorts of things happening because we don’t actually look at the kinds of queries users are running.

One excellent technique to better understand a domain is to sit down with your users while they’re working and ask them, “what made you run that query just now?”, “why that specific set of filters?”.

What I’ve noticed over the years is that our users find very creative ways to achieve their business objectives despite the limitations of the system that they’re working with. We developers ultimately see these as requirements, but they are better interpreted as workarounds.

I’ll talk some more about how a software development organization should deal with these workarounds in a future post, but I want to focus back in on the queries for now.

Oh, and don’t get me started on caching or NoSQL, not that I think that those tools don’t provide value – they do, but they’re only relevant once you know which business problem you’re solving and why.

Not all queries are created equal

Even before bringing up the questions I described in the previous section, any time you get query-centric requirements the first question to ask is “how often will the user be running this specific query?”.

If the answer is that the specific query will be run periodically (every day, week, etc), then drill deeper to see what pattern the user will be looking for in the data. If the person you’re talking to doesn’t know to answer that question, then go find someone who does. Every periodic query I’ve seen has some pattern behind it – and in my conversations with thousands of other developers over the years, I’ve seen that this is not just my personal experience.

But there is a case where a query does get run repeatedly without there being a pattern behind it.

I know this sounds like I’m contradicting myself, but the distinction is the word “specific” that I emphasized above.

There are certain users who behave very differently from other users – these users are often doing what I call research, i.e. the “I don’t know what I’m looking for but I’ll know it when I see it” people.

These researchers tend to repeatedly query the data in the system however they tend to run different queries all the time. This is the reason why traditional data warehouse type solutions don’t tend to work well for them. Data warehouses are optimized for running specific queries repeatedly.

Keeping the Single-Responsibility Principle in mind – we should not try to create a single query mechanism that will address these two very different and independently evolving needs.

And now on to Search

Search is a feature that is needed in many systems and whose complexity is greatly underestimated.

While the developer community has taken some decent strides in understanding that search needs to be treated differently from other queries, the common Lucene/Solr solutions that are applied are often overwhelmed by the size of the data set on which the business operates.

The problem is compounded by our user population being spoiled by Google – that simple little text box and voila, exactly what you’re looking for magically appears instantaneously. They don’t understand (or care) how much engineering effort went into making that “just work”.

Lucene and Solr work well when your data set isn’t too large, and then they become pretty useless as the quality of their results degrades. The thing is that many of us in IT tend to work on projects where we have an unrealistically small data set that we use to test the system and, at these volumes, it looks like our solutions work great. But if you have 20 million customers, do you think a full text search on “Smith” is going to find just the right one?

Larger data sets require a relevance engine – something that feeds off of what users do AFTER the query to influence the results of future queries. Did the user page to the next screen? That needs to be fed back in. Did they click on one of the results? That needs to be fed back in too. Did they go back to the search and do another similar search right after looking at a result – that should possibly undo the previous feedback.

And that’s just relevance for beginners.

You know what makes Google, you know, Google? It’s that they have this absolutely massive data set of what users do after the query that informs which results they return when. You probably don’t have that. That and search is/was their main business for many years – I’m betting that it’s not your main business.

You should discuss this with your stakeholders the next time they ask for search functionality in your system.

In closing

I know that the common CQRS talking points tell you to keep your queries simple, but that doesn’t mean that simple is easy.

It takes a fair bit of domain understanding to figure out what the queries in the system are supposed to be – what tasks users are trying to achieve through these queries. And even when you do reach this understanding, convincing various business stakeholders to change the design of the UI to reflect these insights is far from easy.

It often seems like the reasonable solution to give our users everything, to not limit them in any way, and then they’ll be able to do anything. What ends up happening is that our users end up drowning in a sea of data, unable to see the forest for the trees, ultimately resulting in the company not noticing important trends quickly enough (or at all) and therefore making poor business decisions.

Even if your company doesn’t believe itself to be in “Big Data” territory, I’d suggest talking with the people on the “front lines” just in case. Many of them will report feeling overwhelmed by the quantity of stuff (to use the correct scientific term) they need to deal with.

It’s not about Lucene, Solr, OData, SSRS, or any other technology.

It’s on you. Go get ’em.

Comments [8]
Posted on Sunday, April 28th, 2013.



SOA Course in NYC almost full


Posted in Courses

So, there are just a few spots left for my course in New York on April 8.

If you want to come please don’t wait to register.

We’re also going to be re-recording the course as the recording from Denver turned out pretty bad, only this time with a much more professional crew. This means that attendees will be getting the recording of the course which they themselves attended instead of that of a previous group – an added bonus.

Just as a reminder – if your company won’t pay for the course and you still want to come, there are significant discounts available. Just send me an email to training@udidahan.com.

Hope to see you there.

Register here

* PS – After this will be Stockholm and then London and that’ll be all folks!

Comments [5]
Posted on Thursday, March 28th, 2013.



Uploaded some old “Ask Udi” podcasts


Posted in Ask Udi Podcast

I’ve been able to track down the files for some of my old “Ask Udi” podcasts. I haven’t listened through them again, so it could be that some of the stuff in there is someone dated, and/or that my perspectives have changed, but there is probably some good stuff in there regardless.

Enjoy:

060518ud01.mp3
060808ud01.mp3
060831ud01.mp3
061017ud01.mp3

Comments [2]
Posted on Saturday, March 9th, 2013.



Last round of training


Posted in Courses | SOA | Training

Update: Videos now for sale here.

If you’d asked me last year how long I saw myself jetting around the world giving my SOA course, I probably would have said that I could see myself doing this well into “retirement”. But things change – usually when you least expect it.

In any case, I’ll be giving the course 4 more times, and that’ll be it.

Date City Address Register
Mar 18 Oslo, NO Program Utvikling
Martin Lingesvei 17 – 25
Register
Apr 8 New York, US New Horizons
290 Madison Ave
Register
May 13 Stockholm, Sweden Cornerstone
Svärdvägen 3A, 182 11 Danderyd
Register
June 3 London UK Skills Matter
107-111 Fleet Street
Register

When I was in Denver last month, I had the SOA course professionally recorded so if you can’t make any of these dates, you’ll still be able to get the videos. If you bought the videos in the past, don’t worry, I’ll be getting you the new videos as soon as they’re available. The NServiceBus courses delivered by other trainers will continue to run the same as before.

This change is part of a larger change in priorities for me. There are some big things coming that I’m very excited about that require quite a bit more of my attention.

Anyway, hope to see you either in Oslo, New York, Stockholm, or London.

Comments [8]
Posted on Saturday, February 23rd, 2013.



   


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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.

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“Udi, one of the great minds in this area.
A man I respect immensely.”





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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.”

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“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.”

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Awesome. Just awesome.

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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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