David Anderson observed five core properties to be present in each successful implementation of Kanban. These have become know as the Principles of Kanban.

First adopt the foundational principles…

1. Start with what you do now
2. Agree to pursue incremental, evolutionary change
3. Respect the current process, roles, responsibilities & titles

Then use the Five Core Properties…

1. Visualize the Workflow
2. Limit Work in Progress
3. Manage Flow
4. Make Process Policies Explicit
5. Improve Collaboratively—using models & the scientific method

To get started:

1. Walk the line—Staple yourself to an item and follow its steps through its life.
2. Visualize the workflow—Draw the flow of steps that are taken as a sequence of columns. Use common sense to merge columns.
3. Track all work—For a couple of weeks, put all work as individual items on the board, and track them as they progress.
4. Limit Work in Progress—After some time, and using common sense, put limits on some columns (and swim lanes, if you have them) to increase flow and throughput. Tighten up the limits over time, until it starts hurting. Use the pain to trigger a conversation on how to get rid of the pain while maintaining the limit. Repeat.

Quite a few interesting sessions today:

Google Knowledge Graph

With the Knowledge Graph, Google is trying to give a new dimension to its flagship product: Search.
Users should be able to have a conversation with search, and search should anticipate on a user’s interests by showing related topics.
So search needs to understand the context of searches, in other words: it needs to understand the world. This is where Knowledge Tree comes in handy.
Knowledge Tree is a hugh graph with semantic data about real world entities and their relations. This data has been gathered from Wikipedia, Google+ and many other sources.
The complete tree is viewable and downloadable at freebase.com.
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Today was the first day of the Google IO conference in San Francisco. I was lucky enough to be able to attend so I can share some (personal) highlights of the day.

In the keynote Google showed some of their latest developments:
It is now possible to upload a batch of pictures to your online storage and let Google decide which are the best ones to keep. For instance when you’ve been on holiday and have taken 600 pictures, too many to show to anybody, Google can propose a selection after doing some intelligent analysis:
It can filter pictures if they are dupicates or if they are unclear. But it also recognizes if pictures contain some of your (Google+) relations, which would make them more interesting. Even more cool: with the help of some machine learning and a lot of training, Google can now estimate if a picture is pretty or not.
Another cool feature: Google will recognize if you have multiple pictures of the same person in the same scene. Based on some intrapolation algorithm, it can generate new pictures in that scene. Some examples were shown and they were actually really good. Read more

Like all software, Deployit plugins should be build automatically, deployed and tested whenever possible. Below I will explain how to setup continuous integration and testing for Deployit plugins. The general idea is that if you’re creating a larger set of plugins for Deployit, it makes sense to try to build and deploy them as often as possible so you can catch errors early. We found that it is really easy to create plugins that work fine in isolation but fail when they are deployed together. Luckily it is also easy to catch these kinds of errors as I will show below.
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A few years ago I was asked by one of our customers to help them make better use of their integration layer. Ever since then me and my team have been working on a framework in support of that. This is the fourth in a series of blogs on the development of our framework, and discusses the features it provides. The one that was announced last time, about building blocks, is momentarily postponed.

So far I’ve discussed the goals & challenges surrounding the development activities, but I’d like to focus more on the framework itself now, and what it brings to those that are using it.

As soon as a new party (be it service consumer or service provider) connects to our framework, it can profit directly from the wealth of functionality we deliver out-of-the-box. These ‘generic features’ are exactly what one would expect from a (logical) ESB, and are partly based on the Expanded Enterprise Service Bus Pattern.

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Two days ago, I read the book Toyota Kata by Mike Rother. Like most management books, the central message is hammered home by repetition. Some people, like me, may find that a bit annoying. That does not make this book any less a must read though. If you’re interested in making Lean/Agile really work in your organization without running the risk of organizational gravity eroding all your hard efforts over time, this book has the answer on how to do that. I’ll be incorporating the concepts of the Toyota Kata in my consulting from now on. Empower yourself. Read this book now! Or at least check out my summary of it.

All I wanted to do was create a number of plugins and examples for Deployit using the different techniques available. While working on examples I was frustrated by having to clean up remainders of previous attempts, so following in the footsteps of greater men than my humble self (most notably professor Knuth who created TeX so he could finish writing a series of books on computer science) I first wrote a script to create junk in the Deployit repository and then get rid of it in one sweeping go.
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With all the big-data postings, now something about traditional SQL, running at DB2 9. We had created a web-application, that was basically a view for a database. The application displayed content of a database after the user would enter search parameters, or everything when no parameter was entered. The database contained a few hundred-thousands records. All in all very simple.
The software worked fine at our test-environment. But when we deployed the software into production, it would hardly ever display data. In the logs we found frequent locking errors as follow:

15:23 ERROR (org.hibernate.engine.jdbc.spi.SqlExceptionHelper) – DB2 SQL Error: SQLCODE=-911, SQLSTATE=40001, SQLERRMC=68, DRIVER=4.1

Searching the web revealed what that error meant: a deadlock or timeout has occurred. We knew the same database was also accessed by another application, Activiti running processes written in BPMN. The processes in the Activiti-engine only inserted a few records per minute, so we didn’t expect that application having a big influence. Yet how can a few inserts per minute have such a big impact?
After some talking to a DBA’er and doing our own experimentation we found out about the problem, which will describe here.

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As a software developer you’re using dependency management to handle dependencies on your project; include frameworks and libraries to your project. If you’re a Java developer you’re probably using Maven. When you’re not using Maven you’re probably using one of the more versatile build tools like Ant or Gradle, both can use Ivy for dependency management. Either way, you’re not putting binaries (jars) in your source control repository.

How about your FitNesse acceptance suite? Since it’s all software and all belongs to the project, you probably want to have the same standards when executing the acceptance test suite. It’s really not that different from executing your regular (unit) tests.

In this blog I’ll explain how to launch a FitNesse suite from Maven. I’ll also elaborate on how to get FitNesse to recognize the dependencies required to launch the application. A future post will be dedicated to the FitNesse/Ivy combo.

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There’s an intersting low-level class in the Android SDK called Looper. Each app has at least one, because it powers the UI Thread. You can create Android apps perfectly fine without ever using Looper yourself, but it’s an interesting thing, so let’s take a look under the bonnet.

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