Vishnu Varadaraj's Blog

Parallels vs VMWare Just a mental note to myself to keep off Parallels on Mac if I have a choice, it wasted almost my entire weekend since it had trouble after I upgraded the OS to Leopard & installed new parallels trial. XP image kept on crashing after a Windows update. Finally, I switched to VMWare and had to reinstall all OSes. Hopefully, it is just a problem with the trial copy, but I found VMWare to be trouble free. I had a great opinion about Parallels, but all that changed this weekend. My vote - VMWare!

Ruby on Rails It is hard to be excited over a new language nowadays, but recently I came across one which seemed to make web & database development fun again. I am referring to the combination of Ruby & Rails (RoR). This was a framework built for real world development problems rather than for 'building a framework' as per it's founder. It has several interesting features: 1. Lack of strong typing & support for 'duck typing' - it works even though you feel lost sometimes if you have been a C/C++/Java/C# programmer. 2. Configuration by convention - no need to configure stuff if you follow the convention, but you can configure if you need to as well. 3. Brevity of expression - introduced by C which can easily get you a cult following. eg. one line to write a program which prints itself. 4. Dynamic nature - ability to add methods or redefine methods on the fly - to any class in the system, even built-in ones. 5. script/console - a hidden gem, difficult to l...

The end of SOAP webservices. It is probably a bit early to say this, but SOAP webservices doesn't have a future. I had been a myopic fan of SOAP webservices and one of the early adopters of the technology in various implementations - .NET 1.0, axis, xfire, JAX-WS, BPEL, JSR 180 etc. It is a great example of how excitement about a new technology can blind your judgment. It failed the single most important test - it was just not _simple_ enough to succeed in the long term. 1. complexity meant few stable implementations. eg. jboss changed their webservice implementation twice or thrice already. 2. complexity meant inherent concerns about it's security after deployment. eg. how does it handle a malformed request? 3. it needed client & server support which meant changing platforms as your clients change. eg. javascript, actionscript, java, .NET clients. 4. it was supposed to be cross platform, but it required another standard (ws-i profile xx) to standardize the standard. Still,...

Future of the web. The answer is right in front of you even if you don't see it already: The web started with simple HTML. Then came the dynamic web where content is dynamically generated for the users. Then came the wikis which enabled editable webs. Then web applications got more interactive with AJAX. The next level of interactivity is where applications execute and behave like Desktop applications within the browser. Then there will be the web OS where you store all the important data in the web and access the same from everywhere. * The web OS sounds grand but the closest we have today for the client is Flash/Flex & Silverlight & XUL to a lesser extent. * This will blur the line between desktop apps & web apps further. * Making toy applications for web will no longer fly & traditional players might get another shot. (MSFT vs GOOGL) * The recent acquisition of 'Parakey' by Facebook is an indication of where the future is goi...

Sometimes you have to keep repeating a message so that everyone gets it, at the risk of sounding like a broken record. There was a quote in this month's Popular science which applies to  software world as I had been trying to say in earlier posts- "good engineers find solutions to hard problems that are complex and hard to understand, but great engineers find solutions to hard problems that are so simple that you wonder why you didn't think about it in the first place" Simplicity is not only important in software design but also to the user. I remember working on a product  which had a versioning scheme which was so complex that even the QA required several days of training to understand it. You can imagine the frustration for the customer and how long the feature existed in the product! The next level of simplicity is in the user interface, Microsoft Office 2007 UI is a great example of how to scare the user by showing all options. 37 signals has some good example...

ABCs of good design Good design and architecture has always been identified as a key requirement for a product to succeed in the long term. But how how can you measure the quality of a design or identify the recipe to come up with the best design always? These are not questions with easy answers, but help to illustrate the challenges in the area. There have been many approaches to improve the quality of design in computer software over the course of time: 1. Functions & subroutines - This helped improve the design of monolithic programs by separating commonly used functionality into functions & subroutines. This improved the maintenance and reuse of code by having less duplication etc. 2. OOP - This was another major step forward in design in which we tried to model the objects in real world using classes having methods & properties. This was more natural to humans than working with procedures. eg. Rumbaugh & Booch. 3. CASE - 'Computer aided software engineering...

I have always been a Windows admirer, but a newly converted Mac fan, so it is probably time to see the OS world in a more 'objective' way! Today Linux It is great as a server - controlled environment and free software without support works just fine. It is not a good home machine OS - at least not yet for the typical person who need driver support for his peripherals and who needs to run PC software. Mac OS X It is technically & visually the best OS for a home machine OS out there though a bit expensive & have limited peripherals - great usability & innovation. I expect to see the iSync+.mac integration in the next version of Windows ! It is good as a server - the unix background gives it the required skills, but it is still not acceptable for many businesses as desktop due to lack of support for Outlook etc. Windows It is a good OS for a home machine - the sheer volume of software & peripherals is good. Security is more of a challenge as ...

These should be obvious to anyone who has developed a real software product before. But, recently I had talked to a few people who were working on their first large scale projects on their own but were making some basic mistakes without realizing it. 1. If you are developing a new product or technology, prototyping and research is a must. Agile development methodologies are good, but for a large scale product use agile methodologies after your research phase. 2. Prototyping and research often takes longer than developing the actual product itself. Someone should actually write a prototype which acts as the prototype for modularization & abstraction as well if possible. 3. Always separate your UI code from your non-UI code. Often, the non UI code will be implemented as services in the windows platform. Develop a fool proof mechanism to keep the software upto-date as well. 4. Never try to automate your UI testing first. It should be done only after automating tests for the non-UI...

Story of a website being hacked Hosting a website at home is one thing, but hosting one on the live internet is a whole different ballgame. Yesterday, I decided to expose one of my Xen virtual machines at home to the internet just to see if it works. I wasn't expecting to be hacked in less than an hour though with just 2 ports open. It brought down my jboss server(did a security no-no by running as root- hey, I was running it on XP before! :-), no ssh access etc. It helped that it was a Xen guest, I deleted the disk image and restored my backup. I just had to have more control if someone did attempt to break in again. So, put the machine back live again with more security tools & help from Google. Eg. apache with mod_jk instead of jboss, host FW rules in addition to h/w firewall rules, snort with upto-date rules, did a portscan with nmap, chkrootkit, backed up the system profile with tripwire and checks running every hour with automatic emails to me. I thought this was a good s...

Customers & managing complexity The only reason you should ever be solving a complex problem is if it makes your customer's life so much more simpler. But again, all complexity can be put into this category, so think twice before you do that!