Began Java programming in 2001 in a middleware application in the finance industry (Portfolio Risk Management) with a company that has about half of the worlds top banks as customers. Between the C++ frontend, and database backend, continuous high-performance integration using sockets, concurrency, and tight memory management were my initial constraints. Much of what I learned has been reimplemented in different ways as part of the native Java libraries, and this gives me an insight on the internals and how to take advantage of that.

I have since applied Java (and other languages) in multiple areas and environments, ranging from large-scale hardware including 256-core terabyte machines, clusters of almost 1000 Linux "blades", and much smaller devices like Raspberry Pi's, etc.

Note that I am a 'server-side' specialist. If you are looking for help with AWT, JavaFX or Swing, then I *can* help, but it is not my strength.

20 years is not an exageration. I was installing slackware from floppies in the mid 90's. I have been a "power user" in Linux for many years, and while I don't count myself as a professional-level administrator, I have still done many professional things with it. I *know* how to make it work as part of the solution. I more than just know my way around.

Almost all my applications have concurrency concerns, and I have always been conscious of the best ways to avoid, manage, or accommodate these issues.

I have been involved in systems requiring scalability for almost all my time with Java. I have recently explored the infrastructure Netflix and other enterprises use in the cloud, for example. I have written applications that scale from 1 through to 256 cores on a single machine (IBM Power systems), as well as others that scale out to hundreds of machines.

All my best applications have related to high-performance requirements. I have a strong background in performance tuning, and an instinct for finding the right solutions quickly.

I have some recent experience with Cloud Computing. I am learning it now, as it happens, based on the Netflix model (NetflixOSS).

Databases have been a core part of my systems for "ever". I used to be a Sybase specialist (certified developer in the 90's) but I have had to generalize since then. I am at home as a power-user on almost all commercial database systems now, and can find my way around the open source relational systems as well (Mysql, PostgreSQL, etc.). My instincts in databases are all good, but some of my knowledge is a little rusty.

I am the maintainer of the JDOM open source library (millions of downloads each year). I am well versed in XML, especially as it relates to Java.

I have always been a server-side programmer, with only brief forays in to the GUI aspects. My server-side is my strength.

Personal details

Rolf

Summary

Technical skills