DenkzeitWiki

Large Scale Apps

• Developing large scale applications with dynamic languages
  • Developing large scale applications in Python
    • http://www.egenix.com/
  • Python Success Stories
  • Lisp Success Stories
  
  
• Perl in Large Corporatons (hint: it's about culture, not technology)

Languages don't matter. Technology doesn't matter. It's culture and it is people that matter.

• What I mean is that smart people working within a common culture is the most important thing in building any "large" application (or any application, for that matter).
  • common culture: It should not be possible to distinguish coders by their code.

• Language Wars by JoelSpolsky

The safe answer, for the Big Enterprisy Thing where you have no interest in being on the cutting edge, is C#, Java, PHP, or Python, since there's so much evidence that when it comes right down to it zillions of people are building huge business-critical things in those languages and while they may have problems, they're not life-threatening problems.

• Note the PHP and Python in that statement... (And forget about the cutting edge.)
  
  
• Is there a "Large Scale Python Software Design" ?
  • Python works well for sys-admin tasks.
  • a 10k Python app can be fairly large in terms of end-user functionality.
  
  
• Python Can Survive in the Enterprise -- presentation at PyCon 2006

IDEs have been the last excuse for many people to not use dynamic languages, and it's a very good excuse. But even without a top-notch Python IDE like Wing (wingware.com), I feel more productive in Python + Emacs than in C# + Visual Studio, or Java + Eclipse. [1]

• Writing good (dynamic) code
  • in essence every application (code) is its own language (see DomainSpecificLanguage).
  • sometimes it is better to be not hip but read- and understandable.

"I cannot imagine how the dynamic folks can maintain medium to large projects without refactoring over several iterations over several years of requirement additions and changes."

Perhaps they compose larger software from smaller independent parts, rather than composing large software from large interdependent parts.[2]

• Millions of lines of code

We can focus on reducing the amount of code we manage by using libraries, and there is certainly plenty of that going on in Javaland. We can also add higher-level features to our languages. Doing so reduces the total lines of code required to solve a problem and the cognitive load required to maintain a program.

Think about how many lines of code in Java are wasted on getters and setters that do nothing beyond the standard behavior, and how many times you have to type bar.getFoo() rather than just bar.foo. Yes, I know that Eclipse generates the getters and setters for you, but you still have to read through all of that muck when you’re trying to figure out what a program does.

Some Apps and Figures

• http://wiki.python.org/moin/LargePythonProjects

The relationship between lines of code and bugs is completely linear. Fewer code means fewer bugs. [14]

• Code's Worst Enemy
  • size
• Size Is The Enemy