On the Inviqa techPoral today there's a new post from Lorna Mitchell showing you how to profile your PHP applications with the help of the XHGui tool (and XHProf extension).

Profiling is a technique for observing the performance of an application, ideal for showing up bottlenecks or particularly intensive use of resources. Profiling gets inside your application and gives information about the performance of the various parts of code that are used during a request. [...] We have a choice of tools for PHP but in this article we’ll focus on an excellent tool called XHGui. XHGui is a tool built upon XHProf, the profiling tool released by Facebook, but adding better storage of metrics and a much nicer interface for retrieving information from it, to the extent that it feels like a new tool in it’s own right!

She walks you through the full installation, including other things the tool depends on (like MongoDB and the XHProf extension). She shows how to run the installer, configure a virtual host correctly (using mod_rewrite) and some example screenshots of what the resulting statistics report. This includes things like "wall time" and parts of the application that may be "memory hogs". There's also an example of a handy feature called the "Callgraph" that shows you a visual representation of the performance of the execution of the app.

On the Ibuildings techPortal site, they've posted the latest episode of their "DPC Radio" series (as recorded at the 2011 Dutch PHP Conference) - Rowan Merewood's session "TDD and Getting Paid".

Test-driven development is generally regarded as a good move: it should result in simple decoupled design, your tests tend to cover behaviour not methods, and far fewer bugs. However, just getting unit tests in on a real, commercial project is hard - switching to TDD is even harder. [...] So, instead of beating ourselves up about not being perfect let's look at an interactive approach to adopting TDD principles. We'll look at tactics for selling TDD to your client, boss and colleagues. This talk will also cover methods for making TDD easier for you by showing you what tools you can use to integrate it into your development environment.

You can listen to this new session recording through the in-page player, by downloading the mp3 or by subscribing to their feed.

Following the stepping down of Cal Evans as the Editor-in-Chief of the IBuildings techPortal website, a new community member has stepped up to take on the role - Lorna Mitchell.

Allow me to introduce myself; my name is Lorna Mitchell and I’m your new Editor-in-Chief here at techPortal. This site was grown from an ambition by Ibuildings to allow great content, mostly from Ibuildings developers, to be collected into one place and shared with the wider community. Over time this has grown to include the content from the sessions at DPC (Dutch PHP Conference) in 2009, as well as some shorter technical posts.

In her personal post Lorna also mentions other roles she'll be taking on in the IBuildings PHP Centre of Expertise.

On the Ibuildings techPortal site Stefan Koopmanschap has written up some thoughts on one of the eternal struggles development shops face - whether to buy or build the software they need (either for themselves or their clients).

One of the biggest struggles in any software development company is "Buy vs. Build". How do you strike a balance between writing custom software and purchasing off-the-shelf solutions. This is something that is very hard and everyone gets it wrong every once in a while. In this article we will explore the way that Ibuildings approaches this issue, in the hopes that it helps others in getting it right more often.

He talks about considerations made on both sides - how flexible is the application, what is on-hand that could be adapted - and how the base product they might have purchased can act as a based to work from (like a content management system). There's no overall recommendation, though - too much of the decision depends on what's needed at the time and the capabilities of the technical staff employed.

The Ibuildings group has officially launched their techPortal website - their new "home on the web" that'll provide resources to the community like articles and tutorials as written bu some of the Ibuildings staff.

Cal Evans (once again sporting the title of Editor-in-Chief) has this to say about the site:

techPortal is the place where we will talk about PHP. We work on a lot of interesting projects and get to work with a lot of cool technologies. Our goal with techPortal is to share what we learn with the wider PHP community. Our hope is that you will visit often, read about the technologies with which we are working, and some of it will spark your imagination. Ibuildings believe that Information is only valuable when it is shared. When something you read here helps you, make sure and share what you learn on your blog as well.

The portal has launched with the first article from Lorna Mitchell about memcached and how you can use it to make the load lighter for your application.

Here's a few other comments on the launch: the Ibuildings blog and Lorna Mitchell's blog.